[1965]
1 I.R.	294	
GLADYS RYAN Plaintiff  v. THE ATTORNEY GENERAL Defendant. 
(1962. No. 913 P.)
	14,15, 19, 20, 21, 22, 25, 26, 27, 28, 29,  March 1963 
23,24, 25, 26, 29, 30,  April 1963 
1,2, 6, 7, 8, 14, 15, 16, 17, 20, 21, 22, 23, 24, 28, 29, 30,  May 1963 
17,18, 19, 20, 21, 22, 24, 26, 27, 28,  June 1963 
1,2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 15, 16, 17, 18, 19, 22, 23, 24, 25, 31,  July 1963 
	
Supreme Court.	7,17, 18, 19, 20, 21, 24, 25,  Feb. 1964 
3 July 1964 
	
Constitution of Ireland - Statute - Validity - Provision for fluoridation of watersupplied to public - Whether a violation of personal rights of citizens -Constitution of Ireland, 1937, Art. 40, 3; Arts. 41, 42 - Health (Fluoridationof Water Supplies) Act, 1960 (No. 46 of 1960), s. 2, sub-ss. 1, 2 and 3;ss. 3, 4 - Fluoridation of Water Supplies (Dublin) Regulations, 1962 (S.I.,1962, No. 75), Arts. 3, 5, 6, 8.
 The Health (Fluoridation of Water Supplies) Act, 1960, by s. 2, sub-ss. 1, 2 and 3, imposes an obligation on a health authority (as therein defined) to arrange for the fluoridation of water supplied to the public by sanitary authorities, through pipes, before a date to be fixed by the Minister for Health. The Minister is empowered to make regulations which shall "in particular provide for the specification of the amount of fluorine (which shall not exceed one part by weight of fluorine per million parts of water) which may be added to a water supply." By s. 2, sub-s. 4, of the Act, prior to making such regulations the Minister is required, inter alia, to cause to be made a survey of the incidence of dental caries in a representative sample of pupils attending full-time day schools in the functional areas of a health authority to which the regulations relate and also to have an analysis of, inter alia, the quantities of fluorine in the water supplied by sanitary authorities through pipes to the public in such functional areas. Pursuant to the Act, the Minister, in 1961, caused a survey of the incidence of dental caries among children in, inter alia, the Dublin area to be carried out by the Medical Research Council and he also caused to be made an analysis of the piped water in this area by the public analyst for the City and County of Dublin. The reports of the survey and analysis were subsequently presented to the Oireachtas. On the 5th May, 1962, the Minister, in exercise of his powers under ss. 2 and 4 of the Act, made the Fluoridation of Water Supplies (Dublin) Regulations, 1962 (S.I., 1962, No. 75), which required the Dublin Health Authority to arrange for the fluoridation, inter alia, of the piped water supply provided by the Corporation of Dublin. Article 5 of these Regulations provided that "The amount of fluorine which may be added to a water supply in accordance with these regulations shall be such that the water, after the addition of the fluorine, shall contain not more than one part of fluorine per million parts of water, and not less than eight-tenths of a part of fluorine per million parts of water."
 The plaintiff, the mother of five children, who resided in the City of Dublin and whose house was connected with the public piped water supply of the Dublin Corporation, claimed that the provisions of s. 2, sub-ss. 1, 2 and 3 and ss. 3 and 4 of the Act were void on the grounds 1, that they violated her rights and those of her children under Art. 40, 3, of the Constitution; 2, that they were a violation of the authority of the family under Art. 41 and a violation of the family's right to physical education of the children under Art. 42 of the Constitution.
Held by the High Court (Kenny J.) 1, that legislation dealing with the contents of food or drink does not in any way affect the authority of the family and the Act of 1960 is not an interference with the rights guaranteed to the family by Art. 41 of the Constitution;
 2, That the word, "education," in Art. 42, 1, of the Constitution is not used in its former wide sense which included "rearing and nurturing." The education referred to in Art. 42, 1, having regard to the words of section 2 of the said Article ("Parents shall be free to provide this education in their homes or in private schools or in schools recognised or established by the State"), must be of a scholastic nature. Therefore, the fluoridation of the public water supply (even if it be harmful) does not interfere with or violate the rights given to the family and to the parents by Art. 42 of the Constitution;
 3, That the High Court has jurisdiction to consider whether an Act of the Oireachtas respects and, as far as practicable, defends and vindicates the

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 personal rights of the citizen and to declare the legislation unconstitutional if it does not do so;
 4, That the general guarantee of personal rights in section 3 (1) of Art. 40 extends to rights not specified in Art. 40. One of the personal rights of the citizen protected by the general guarantee is the right to bodily integrity; the fluoridation of the public water supply, even if it be dangerous, is not a violation of the plaintiff's right to bodily integrity;
 5, That there is no contractual right to a piped water supply. PerKenny J.:—"The plaintiff has no legal right to a supply of piped water and the Act of 1960 does not impose any obligation on her or on the members of her family to drink or use the water coming through the piped water supply. . . . the plaintiff probably has a right of access to a supply of water, but this does not give her a right to a supply of water which has not been fluoridated through the piped water supply. . . . I am satisfied that the plaintiff . . . can, by the expenditure of a few pounds, remove all or almost all the fluoride ions from the water coming through the piped water supply."
 6, That from the evidence adduced the Court was satisfied that the fluoridation of the public water supply at the concentration of 1 p.p.m. would not, in this temperate climate, be dangerous to anybody nor was there a reasonable possibility that it might involve an element of danger or risk to life or health of the citizens of this country.
 Accordingly, the plaintiff's action was dismissed.
 On appeal by the plaintiff to the Supreme Court it was held by the Supreme Court ( Ó Dálaigh  C.J., Lavery, Kingsmill Moore, Haugh and Walsh JJ.), dismissing the appeal, 1, that the question, whether or not a citizen's constitutional rights have been infringed by the kind of water provided by the public water supply, should not be controlled by technical limitations arising from the law of contract;
 2, That, on the question whether the plaintiff's action failed because she could, by a simple and inexpensive device fitted to the tap, remove from the water the fluoride ions (which ground was not relied upon by the Attorney General), a fuller examination than had been given to the matter in the evidence would be required by the Court before accepting it as affording, by itself, a satisfactory answer to the plaintiff's claim;
 3, That the "personal rights" mentioned in section 3, 1, of Art. 40 of the Constitution are not exhausted by the enumeration of "life, person, good name, and property rights" in section 3, 2, as is shown by the use of the words "in particular" in section 3, 2, nor by the more detached treatment of specific rights in the subsequent sections of Art. 40. The Court considered that it was unnecessary, in this case, to attempt to list the rights which properly fall within the category of "personal rights";
 4, That it was unnecessary for the Court to define "bodily integrity" or the "right to the integrity of the person";
 5, That the findings of the trial Judge that the fluoridation of the public water supplies in this country at a concentration of 1 p.p.m. would not cause any damage or injury to health and that there was no risk or prospect that it would do so were correct and could not be challenged;
 6, That the changes effected by drinking the public water containing fluoride ions at a concentration of 1 p.p.m., do not amount to a violation of the"bodily integrity" of the plaintiff or her children;
 7, That it is not accepted that the proposed fluoridation of the water supply is, or could be described as, mass medication and it is a misuse of words to refer to this process as mass medication or mass administration of drugs;
 8, That there is nothing in the Act which could be said to be a violation of the guarantee on the part of the State to protect the family in its constitution and authority, contained in Art. 41, 1, 2, of the Constitution;
 9, That the provision of suitable food and drink for children is nurture, not education. Accordingly no question arose concerning a violation of the provisions of ss. 1 and 2 of Art. 42 of the Constitution. PerÓ Dálaigh  C.J.:—"To give him" [a child] "water of a nature calculated to minimise the danger of dental caries is in no way to educate him, physically or otherwise, for it does not develop his resources";

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1 I.R.	Ryan v. The Attorney General.
Kenny J.	296

 10, That the word "fluoridation" in the Act of 1960 is to be given its technical and scientific meaning, except in so far as this is clearly and expressly modified or extended by the wording of the definition, and the extension by the words "fluorine in any form" must be read as "the fluoride ion as contained in or produced by any form of chemical substance."
 11, That although the provisions of s. 2, sub-s. 3 (a), of the Act of 1960 clearly state that the Minister for Health may make regulations which authorise a maximum addition of one part by weight of fluorine per million parts of water to be made to an existing water supply, and do not advert to the natural fluorine content of that supply before such addition so that a concentration in excess of 1 p.p.m. F. was a possible result, nevertheless the Court would not offer an opinion upon the matter as the plaintiff had not adduced evidence to support an examination of it.
 12, That the Court had no concern with the legislative policy of the Oireachtas. The Court's function was to examine the statute in which that policy is embodied so as to discover whether its provisions contravene the provisions of the Constitution.

Witness Action.
 This was an action brought for the purpose of challenging the constitutional validity of the Health (Fluoridation of Water Supplies) Act, 1960, which Act was passed by the Oireachtas on the 28th December, 1960.
 The plaintiff, Gladys Ryan, resided at Grace Park Road, Drumcondra, in the city of Dublin, with her husband and five children, aged from fourteen years to four years. Her dwelling-house was connected with the public piped water supply of the Dublin Corporation and there was no alternative water supply. The nearest unpiped water supply was about three miles distant at Ballymun in the County of Dublin. The plaintiff objected to the proposed addition of fluorine to the public water supply as she considered it an infringement of her parental rights and also an infringement of her personal integrity. The facts have been summarised in the head-note and appear fully in the judgment of Kenny J., post.
Sean MacBride S.C. , T. J. Conolly S.C. , Seamus Egan S.C. ,and J. B. O'Quigley , for the plaintiff.
The Attorney General, W. D. Finlay S.C. , Seán Butler S.C. and J. Lovatt-Dolan  for the defendant.
 The arguments were substantially the same as those in the Supreme Court, reported post.
Cur. adv. vult.

Kenny J.:—
	31 July 

 In this case which has been at hearing for 65 days, the plaintiff, Mrs. Gladys Ryan, who lives in Dublin, challenges the constitutional validity of the Health (Fluoridation of Water Supplies) Act, 1960. This Act (which I propose to call

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 "the Act of 1960") was passed on the 28th December, 1960. Sect. 2 of it provides that every health authority is to arrange for the fluoridation of water supplied to the public by sanitary authorities through pipes and that the Minister for Health may fix a date before which any specified health authority is to arrange for the fluoridation of water derived from a particular public water supply. "Health authority" in the Act of 1960 means the Dublin Health Authority, the Waterford Health Authority, the Cork Health Authority, the Limerick Health Authority and every county council which does not appoint members to any of these four health authorities. The result is the creation of a statutory obligation binding every health authority in this country to fluoridate its water supplies coming to the public through pipes before a date to be fixed by the Minister.
 The Act of 1960 gives the Minister power to make regulations: these must provide "for the specification of the amount of fluorine (which shall not exceed one part by weight of fluorine per million parts of water) which may be added to a water supply." Before the Minister makes any regulations he must have a survey carried out "of the incidence of dental caries in a representative sample of pupils attending full-time day schools" in the functional area of the health authority to which the regulations relate and he must also have an analysis carried out of the quantity of fluorine in the water supplied by sanitary authorities through pipes to the public in the functional area of the health authority to which the regulations relate. A report on this survey and on the analysis of the water before it is fluoridated must be presented to each house of the Oireachtas.
 The principal features of the Act of 1960 are:—
 (1) It imposes an obligation coming into force on a day fixed by the Minister on every health authority to put fluorine to an extent not exceeding one part per million by weight into the piped water supplies reaching the public;
 (2) It does not impose an obligation on anyone to drink or use the water which has been fluoridated;
 (5) It does not give to anyone a right to a supply of piped water and it does not alter the position which existed before the Act of 1960 was passed in which those who got supplies of water through pipes did so under a contract with the local authority and not by reason of any legal right which existed apart from that contract; and
 (4) It does not make it unlawful to extract fluorine out of the water coming to homes.

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1 I.R.	Ryan v. The Attorney General.
Kenny J.	298

 In 1961 the Minister had a report on the incidence of dental caries in school children in the Dublin, Kildare and Wicklow health authority areas carried out and he also had an analysis made of the water in each of the public piped water supplies in those areas. The report showed a most alarming rate of dental caries among children between the ages of 5 and 17 while the analysis showed that there is very little naturally-occurring fluorine in the piped water supplies of the Dublin health authority area. The fluorine content of the piped water supplies in the Dublin health authority area is less than 0.1 p.p.m. except in the Balbriggan/Skerries supply area where it is 0.15 p.p.m., in the Rush supply area where it is 0.1 to 0.15 p.p.m., and in the Kiltiernan/Ballaly supply area where it is 0.2 p.p.m. The method of analysis used enabled the fluorine content of water to be determined down to the level of 0.1 p.p.m.
 On the 15th May, 1962, the Minister made regulations (Statutory Instrument No. 75 of 1962) dealing with the Dublin health authority area. They provide that the Dublin health authority is to arrange for the fluoridation of the piped water supply provided by the Dublin Corporation and of other piped water supplies in Dublin. They also provide that the amount of fluorine which may be added to a water supply shall be such that the water, after the addition of the fluorine, shall contain not more than one part of fluorine per million parts of water and not less than 8/10 of a part of fluorine per million parts of water; the fluorine may be added to the public water supply either in the form of sodium fluoride or in the form of sodium silico fluoride. There is also a provision that the fluorine content of the public water supplies which have been fluoridated are to be determined each day by a colorimetric method and, in addition, is to be determined by a distillation method at intervals not exceeding four weeks. The regulations also provide that the sodium fluoride which is to be added to the public water supply is to contain a minimum of 98 per cent sodium fluoride (Na F) by weight and thus provide 44.3 per cent available fluorine while, if sodium silico fluoride is used, it is to contain 98 per cent of that substance and thus provide 59 per cent available fluorine. Therefore, the relationship of sodium fluoride to what the Act of 1960 and the regulations call fluorine but which would have been more accurately described as the fluoride ion is that 98 per cent sodium fluoride gives 44.3 per cent fluoride ion, or, putting it another way, that you get the amount of fluoride ion in sodium fluoride by dividing the amount of the percentage of sodium fluoride by 2.2.
 I have used the word, "fluorine," when stating the effect

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 of the Act and of the regulations because it is the word used in them; the words, "fluoride ion," would, however, have been more accurate. Indeed, much of the controversy in this matter results from the absence of an agreed terminology. The words, "fluorine," "fluoride," the "fluoride ion" and"sodium fluoride," have been used by the witnesses with different meanings and the same unfortunate confusion is found throughout the scientific writing on the subject. "Our speech has its weaknesses and its defects, like all the rest. Most of the occasions for the troubles of the world are grammatical"(Montaigne: Apology for Raymond Sebond). It is therefore necessary to say something about the chemistry of the fluoride ion if only to explain the sense in which I use these words.
 In chemistry most elements have several distinct manifestations. They may be listed thus:—
 (1) Their atoms, or molecules consisting of those atoms, may exist in a free state as elements;
 (2) Their atoms may become ionised by the loss or gain of an electron or electrons and thereafter exist as ions of the element;
 (3) Atoms or ions of the element may join with other ions to form compounds;
 (4) An atom or atoms of the element may become bonded with carbon and then exist as an organic compound of the element.
 The atoms of an element are all alike and possess characteristics unique unto themselves. Similarly ions of that element, derived from atoms which have lost or gained an equal number of electrons, are also all alike and possess unique characteristics. The addition or removal of one or more electrons to or from the atom brings about this phenomenon, and for this reason atoms and ions of the one element have different characteristics and behave differently. There are also differences between compounds of an element and its atoms or its ions. Moreover, the organic and inorganic compounds of an element have properties which the other does not possess.
 The element fluorine does not occur in the free state in nature. It can be produced only in the laboratory and, when this is done, the free element is a noxious gas which reacts violently with many other substances. Throughout the remainder of this judgment I propose to use the word"fluorine" to mean the gas produced in a laboratory. Fluorine is not used in the process of water fluoridation. In

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 nature, fluorine is found only in combination with other elements. In the solid minerals fluorine is present in the form of negatively charged fluoride ions in the crystal lattice paired off with positively charged ions of some other element. For example, in calcium fluoride the fluoride ions are combined with calcium ions. The fluoride ion differs from the atom of fluoride in that it possesses one additional electron.
 When the compounds containing fluorine percolate out of the rocks by water action, they give a very weak solution in water and the positive and negative ions are separated by molecules of water and ions derived from water. The calcium and fluoride ions exist in solution as separate entities with properties completely independent of those of the compound or source from which they were derived. The same is true of sodium and fluoride ions when solid sodium fluoride is dissolved in water. All ions of fluorine, irrespective of their compound of origin, are the same and do exactly the same things in a chemical and in a bio-chemical sense. The fluoride ion naturally present in waters is derived from the solution of a wide range of minerals. In sodium fluoride, the fluorine exists as separate particles (ions) which have an electrical charge. When these substances dissolve in water at low concentration, the fluoride ions pass into solution and exist in the solution as separate entities with properties completely independent of the salt from which they were derived. Thus, the fluoride ions in a solution of calcium fluoride or sodium fluoride are identical and will do exactly the same things in a chemical sense.
 In the language of chemistry substances like calcium fluoride and sodium fluoride are called inorganic substances. This has nothing to do with their location in nature for inorganic substances may be found in minerals or in the body of a living creature. Fluorine is known to combine with the element carbon and, in the language of chemistry, any compound of fluorine with carbon is called an organic substance. The known organic compounds of fluorine are extremely stable and do not dissociate to give fluoride ions in water solutions. Small quantities of the fluoride ions exist naturally in most water supplies and are to be found in practically all foods. Although water usually contains small quantities of the fluoride ion, it does not contain organic compounds of fluorine. Fluoridation of the water supplies involves the addition of a soluble fluoride (sodium fluoride, sodium silico fluoride, or fluorspar) to the water. The process of fluoridating the water supply does not, therefore, add a substance that is foreign to the water but it brings about a small difference in the concentration of the fluoride

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 ions already present. The naturally occurring fluoride ions and the fluoride ions added by the process of fluoridation are chemically identical and there is no distinction between them. There is no change in the colour, taste or odour of water which has been fluoridated.
 One of the features of the fluoride ion is that those who as children have for some time drunk water in which the ion is present at a concentration of 1 p.p.m. or more have less dental decay than those who as children have drunk water containing a minute quantity of the ion only. About 70 years ago dentists and medical observers noticed that those who drank water with a concentration of the fluoride ion of 5 p.p.m. had some mottling of the enamel of their teeth and that they had less dental decay than was to be found in others coming from places where the ion was in the water in minute quantities.
 This association of a lower rate of dental decay with the presence of the fluoride ion at a concentration of 1 p.p.m. or more has been confirmed by a number of careful modern assessments of the prevalence of dental decay in some cities in the United States of America. These have shown that a high rate of dental decay goes with an absence of a recognisable amount of the fluoride ion in the drinking water and that a much lower rate of dental decay is associated with the presence in the water of the ion at a concentration of 1 p.p.m. or more. The most striking of these assessments were those carried out in the two communities of Newburgh and Kingston, both of which are in the State of New York. In each of them there was a low concentration of the fluoride ion in the public water supply. The water in Newburgh was treated with sodium fluoride to bring the concentration of the fluoride ion in it up to 1.0 to 1.2 p.p.m. but the water of Kingston was not fluoridated. The dental and general health of the children in the two communities has been exhaustively examined and compared; a most striking reduction in the rate of dental decay among the children in Newburgh has been found and no ill effects on the general health of those living in that community have been observed. I have heard much evidence on this Newburgh/Kingston experiment: the results of it are accurately summarised, so far as dental health is concerned, in an article by Zachary M. Stadt, called "Resume of dental benefits of fluoride ingestion," in a book, "Fluoridation as a Public Health Measure," published in 1954 by the American Association for the Advancement of Science. I propose to quote some passages from the article:—"At Newburgh, New York, after 60 months of fluoridation, the percentage of 5- to 6-year-old children with all deciduous

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 cuspids and first and second molars caries-free, had increased from 18.2 to 49.2 for a relative increase of 170 per cent: during the same period at Kingston, New York, the control city, there was an increase in the same age group from 21.9 to 30 per cent, a relative increase of 37 per cent. At Brantford, Ontario, after 77 months of fluoridation, the percentage of the 5-16 age group which demonstrated no present or past history of caries in the deciduous or the permanent teeth had increased from 5.18 to 15.9 per cent for a relative increase of 208 per cent in the number caries free. At Sheboygan, Wisconsin, after 65 to 66 months of fluoridation, the number of caries-free children with no carious lesions of the deciduous teeth in the kindergarten group, 5- to 6-years-old, increased from 20.4 to 47.8 per cent, or an improvement of 134 per cent; and in the group 12- to 14-years-old, the number of children with caries-free permanent teeth increased from 2.77 to 4.2 per cent, an improvement of 51 per cent. At Evanston, Illinois, after 48 to 58 months, the number of children with immune deciduous dentition decreased by 20.2 per cent for the 6-year-olds, 6.0 per cent for the 7-year-olds, and 5.7 per cent for the 8-year-olds. This was the only one of the seven communities in which consistently negative results were recorded for the deciduous teeth. After 52 months of fluoridation in Ottawa, Kansas, where the communal water supplies previously had contained 0.3 p.p.m. fluoride, the results were indecisive for both the deciduous and permanent teeth of 6- and 7-year-old children. In Madison, Wisconsin, 46.76 per cent of the 5-year-old children had no carious deciduous teeth after 42 months of fluoridated water consumption in contrast to 25.56 per cent in the same age group during the year before the beginning of fluoridation. After 57 months of fluoridation in Lewiston, Idaho, the percentage of children with caries-free permanent dentition had increased by 68 per cent, 58 per cent and 148 per cent respectively, in the 6-, 7-and 8-year-old age groups."
 "None of these communities is strictly comparable with another by reason of differences in location, economic status, nutrition status, ethnic origin of the inhabitants, amount of fluoride added, different method of caries evaluation, etc. Despite these facts, the increases in the number of children with caries-free dentition in 5 of the 7 communities are remarkably alike."
 "Effect on dental caries incidence in deciduous teeth. In Table 5 is presented a tabulation of the effects of fluoridation of public water supplies over periods varying from 30 to 78 months in 8 communities. Again there has not been uniformity in the methods used for estimating and recording of

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 dental caries experience; however, the available results demonstrate beyond all reasonable doubt that there is an overall lower incidence of tooth decay in the deciduous teeth after 31/2 or more years of fluoridated water consumption. For example, values are presented for the caries incidence of deciduous teeth of 6-year-old children from 7 out of 8 of these communities. In 6 of these 7, the following percentage reductions in carious deciduous teeth was observed: Grand Rapids, Michigan, 53.7; Newburgh, New York, 45.6; Brantford, Ontario, 49.1; Sheboygan, Wisconsin, 53.7; Evanston, Illinois, 7.0; Ottawa, Kansas, 10.0."
 "Effect on dental caries incidence in permanent teeth. In Table 6 are recorded the available data of the effect of fluoridated water consumption on the incidence of dental caries in the permanent teeth of the children from 10 communities where fluoridated water has been consumed for as little as 24 months to a maximum of 78 months. Obviously, only a few of the reports on permanent teeth concern children who have been exposed to fluoridated water from birth; hence the reductions noted are of a preliminary nature and cannot be considered the maximum to be expected when the full development dental period has occurred during fluoridation."
 "For the 6-year-olds, the following percentage reductions for the permanent teeth were noted: Grand Rapids, Michigan, 66.6; Newburgh, New York, 77.6, Brantford, Ontario, 73.2 Marshall, Texas, 63.0; Evanston, Illinois, 73.6; Lesiston, Idaho, 76.8; Ottawa, Kansas, 15.0; and Charlotte, North Carolina, 9.0 for the white children."
 "It is interesting to compare the dental caries incidence in first permanent molars after four years of fluoridation at Newburgh with the incidence prior to fluoridation and in the control city of Kingston. These data are presented for the 6 to 9 and the 10 to 12 years age groups in Table 7 and Figure 1. In the 6 to 9 age group, caries-free first permanent molars in Newburgh increased from 58.9 per cent to 76.9 per cent between the 1944/45 and 1949/50 examinations, an absolute increase of 18 per 100 first molars. In contrast, at Kingston the number of caries-free first permanent molars remained almost unchanged. The number of missing first permanent molars was reduced 60 per cent in Newburgh compared to a 23 per cent reduction at Kingston. The increase in the number of filled molars was approximately the same in both cities, indicating the same amount of dental services in both places. The most striking observation by the authors was the remarkable reduction in the percentage of untreated caries of the first permanent molars at Newburgh: 68 per cent compared with 36 per cent at Kingston."

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 There is also cogent evidence from Ireland of the association of the fluoride ion at a concentration of 1 p.p.m. in the drinking water with a significant reduction in dental decay. One of the surveys carried out under the Act of 1960 related to the health authority areas of Cork, Limerick and Waterford and an unusual concentration of the fluoride ion in the water drunk by those who live in Patrickswell, County Limerick, was found. This concentration and the state of dental health in children in Patrickswell is dealt with in a report presented to the Oireachtas. I propose to quote a passage from the report:—
 "After the dental caries survey team had completed their examinations of children in the selected schools in Limerick City and County, it was discovered that the public water supply serving the village of Patrickswell has a fluorine content of around 0.7 to 1.0 p.p.m. No other water supply in the City and County of Limerick was found to contain fluorine to any significant extent.
 Up to 1949 this small village of 300 people was dependent on a local well for its water supply. In that year a public supply, drawn from a deep boring, was provided. Initially two public fountains were connected to this supply, for use by the inhabitants of the village. During 1951 a large proportion of the houses in the village were connected to the supply and many of the remaining houses were connected in subsequent years.
 As fluorine is not one of the substances normally looked for in the periodic analysis of public water supplies, the presence of fluorine in this supply was unsuspected until, in the course of the present series, an analysis of the Patrickswell supply, carried out on the 22nd March, 1962, specifically to establish whether or not the supply contained fluorine, showed that in fact it did to the extent of 0.95 parts per million. In view of this finding, two further analyses were made at intervals of some weeks; these showed a fluorine content of 0.7 and 1.0 parts per million respectively.
 As Patrickswell National School did not happen to be one of the schools selected at random for the purpose of the dental caries survey in the Limerick area, the Medical Research Council of Ireland were asked to have a special examination carried out of the teeth of the children attending Patrickswell school. This dental examination was carried out by 3 of the 5 dentists who carried out the dental examinations in the Limerick area, using procedures identical to those employed in the latter examinations. The dentists when examining the teeth of the Patrickswell children and when recording

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 the results of the examinations, had no knowledge of the particular water supply used by the children and took no part in the ascertainment of the water supply used by them.
 On the basis of experience in other countries, it should be expected that even in this small community the results, in relation to dental caries status, of the ingestion of water containing fluorine should be apparent. The special examination of the teeth of the children attending Patrickswell National School does, in fact, show that the teeth of the children who have been using the naturally fluoridated public water supply in that village since birth or for the greater part of their lives have appreciably less dental caries than the other children attending the schools and children in the rest of the City and County of Limerick. Thus, while the number surveyed is small, the general pattern of the findings corroborates the beneficial effect of fluoridated water.
 Of 142 Patrickswell school children who were examined it was found that 72 had been exclusively using the public water supply since birth or for the greater part of their lives, 56 had been using water from other sources and 14 had used both types of water. A comparison has been made in Table I of Appendix IV of the dental caries rate of (a) 71 children using the naturally fluoridated public water supply, (b) 54 children using other supplies, and (c) children of the same age groups covered by the survey carried out in other schools in the Limerick health authority area. (The three 14 year-old children examined are not included in this table because no valid conclusion could be drawn from so small a sample). The average dental caries rate among children attending Patrickswell school who did not use the naturally fluoridated supply is very similar to the average dental caries rate among children in the Limerick health authority area as a whole, whereas the dental caries rate of the children using the Patrickswell public water supply is markedly lower. The average DMF (decayed, missing, filled) rate among children who since birth, or for the greater part of their lives, have been using the naturally fluoridated public water supply in Patrickswell is 52 per cent lower (deciduous teeth) and 38 per cent lower (permanent teeth) than among the Patrickswell children not using this naturally fluoridated source, and 53 per cent lower (deciduous teeth) and 34 per cent lower (permanent teeth) than among the children in the rest of Limerick City and County, in which no public water supply has been found to contain fluorine to any significant extent.
 The percentage of children ages 5—14 years of age using the Patrickswell public water supply who are free from caries in their permanent teeth (47 per cent) is appreciably higher

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 than among Patrickswell children who did not use the public water supply (20 per cent) and than among children of the same age group examined in the rest of Limerick City and County (32 per cent).
 It might be noted that the 71 children shown as using the Patrickswell public water supply include a number who did not commence using this supply until early childhood; these would not have obtained the maximum beneficial effect on their teeth of this naturally-fluoridated water. Six of the 13-year-old children did not commence using this fluoridated water supply until their third year of life. All seven of the 12-year-olds did not start using it until they were within 1 and 2 years of age."
 The results of the surveys made at Anglesey also show an association between the ingestion of water containing a concentration of 1 p.p.m. of the fluoride ion and a reduction in the rate of dental decay among children. I shall be referring to these surveys in a later part of this judgment.
 The evidence that the ingestion of drinking water containing a concentration of about 1 part per million leads to a significant reduction in the rate of dental caries among children is, in my opinion, coercive. I accordingly find that the ingestion of such water (whether the fluoride ion occurs naturally in it or is introduced into it) produces a marked reduction in dental caries among children.
 All the writing on the subject shows that the rate of dental decay among children living in the sophisticated and wealthy countries of Western Europe and North America is a serious problem. The causes of this are still a matter of debate; many theories about it have been put forward during the case but, fortunately, it is not necessary for me to make any finding on this matter as it is not relevant to any of the issues I have to decide. Professor Steyn, who came from the Union of South Africa to give evidence for the plaintiff, dealt with this topic in a very vivid way. He said that the preponderance of evidence showed that fluorine builds up the tooth enamel and makes it caries-resistant. He went on to say that caries is the most serious disease of our civilisation, not merely because it causes bad teeth but because bad teeth run down the human system and he added that it was desirable that modern societies should take steps to deal with the problem of dental caries. Another indication of the gravity of the problem is to be found in a passage in a report made under the Act of 1960 and presented to the Oireachtas on the incidence of dental caries in school children in the Dublin, Kildare and Wicklow health authority areas in 1961. The report contains this passage:—"It will be observed from these tables that, apart

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 from girls in Kildare of 7 years of age, only about 4 per cent to 5 per cent of the children have caries-free temporary dentitions and that at 6 years of age about one-fifth of the children have 10 or more decayed or missing or filled temporary teeth. In the case of permanent teeth the percentage of children with dentitions free of caries drops practically to zero at about 14 years of age and at this stage about one-third of them have 10 or more carious teeth. At the later ages in this range the number of children examined is getting smaller so that one cannot expect complete regularity in the sequences. Nevertheless, the continued decline with increasing age in the proportion of children with caries-free permanent dentitions is most marked. In fact, of 911 children aged 15—18 years who were examined in the three areas only one single case of caries-free permanent dentition was found while of the 588 children aged 14 years, only 7 had caries-free permanent dentitions." In the summary which is part of the report it is stated that the survey discloses an extremely high individual incidence and a widespread prevalence of dental caries (decay) among school children attending full-time day schools in the City and County of Dublin and in the Counties of Kildare and Wicklow and that the incidence and prevalence were uniformly high throughout the three areas. It is also stated that among the children in the age group 15 to 18 years only one child was recorded as being entirely free of caries experience.
 This evidence establishes beyond doubt that dental caries in children is a pressing problem and that its prevalence is likely to increase. It also establishes that this disease will have an ever-increasing bad effect on the health of the members of this community unless it is checked. Those who support the fluoridation of the public water supplies have never claimed that it will do away with the disease: what they claim is that it will significantly reduce its prevalence.
 This case was at hearing for 65 days during which a great volume of scientific and medical evidence was given. This could easily lead to the belief that the High Court has jurisdiction to pass judgment on the policy and advisability of legislation and to substitute a judicial view of policy and advisability for that of the Oireachtas. The issue of the advisability or desirability of legislation is a matter for the Oireachtas only, for it has the sole and exclusive power of making laws for the State (see Article 15, 2, of the Constitution.) The jurisdiction (created by the Constitution) of the High Court relates not to the advisability of legislation but to the issue whether the Act under examination contravenes any provision of the Constitution or involves a violation

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 of or interference with the rights given by the Constitution to every citizen. It is, therefore, necessary to consider the relevant provisions of the Constitution, for only in this way can the questions and issues which the Court has to determine be stated.
 The plaintiff's case is that the Act of 1960 is invalid because (1) it is a violation of the inalienable and imprescriptible rights guaranteed to the Family by Article 41 of the Constitution; (2) it is a violation of the inalienable right and duty of parents to provide, according to their means, for the religious, moral, intellectual, physical, and social education of their children given by Article 42 of the Constitution; and (3) it is a breach of the guarantee in Article 40, 3, of the Constitution by the State "in its laws to respect, and, as far as practicable, by its laws to defend and vindicate the personal rights of the citizen." On this third branch the plaintiff puts forward two independent contentions. The first is that Article 40, 3, gives her a right of bodily integrity and that the Oireachtas in passing the Act of 1960 has not respected that right. The other contention is that the fluoridation of the public water supplies is or may be dangerous to the health of all or some of the citizens and, therefore, that in passing the Act of 1960 the Oireachtas has failed to respect and, as far as practicable, by its laws to defend and vindicate the right of the citizen to life and to bodily integrity.
 All the Articles of the Constitution relied on are in that part of the Constitution which is headed, "Fundamental Rights." Article 41 which deals with the Family provides in section 1, sub-s. 1:—"The State recognises the Family as the natural primary and fundamental unit group of Society, and as a moral institution possessing inalienable and imprescriptible rights, antecedent and superior to all positive law," while sub-s. 2 provides:—"The State, therefore, guarantees to protect the Family in its constitution and authority, as the necessary basis of social order and as indispensable to the welfare of the Nation and the State." Not one of the counsel in this case has attempted to state what the inalienable and imprescriptible rights of the Family are and, as the Constitution gives little help on this, I am in some difficulty in dealing with this argument. "Inalienable"means that which cannot be transferred or given away while"imprescriptible" means that which cannot be lost by the passage of time or abandoned by non-exercise. The right of the Family to educate the children of that Family is, I think, one of the rights which any moral philosophy would recognise but this right cannot, in my opinion, be one of the rights referred to in Article 41 for there is a separate Article (Article

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 42) dealing with Education and it is highly unlikely that the Constitution gives the Family two separate rights to educate, one in Article 41 and the other in Article 42, particularly as the right given by Article 42 is detailed in five separate sections in that Article. Some clue to the ambit of the rights of the family referred to in Article 41 is to be found in sub-s. 2 of section 1 where there is a reference to a guarantee by the State to protect the family in its constitution and authority. It seems, therefore, that the rights referred to in section 1, sub-s. 1, of Article 41 relate to the constitution and authority of the family. It was argued by the plaintiff's counsel that the addition of the fluoride ion to drinking water affected the authority of the family to decide what drink and food the members of the family should consume and that the Act of 1960 was, therefore, an attack on the authority of the Family. If it be assumed for the purposes of this argument that fluoridation of water is capable of being a violation of any right, it does not seem to me that it in any way affects the authority of the family. At the time when the Constitution was enacted, there were a number of Acts of Parliament in force which prescribed minimum standards and contents for food and drink and I am entitled to take this legal background into consideration when interpreting the Constitution. In my opinion, legislation dealing with the contents of food or drink does not in any way affect the authority of the Family and the Act of 1960 is not an interference with the rights guaranteed to the family by Article 41.
 The next branch of the plaintiff's case is that the Act of 1960 is invalid because it is an interference with the right given by Article 42 to the family and to the parents to educate the children of the family. Section 1 of Article 42 provides:—"The State acknowledges that the primary and natural educator of the child is the Family and guarantees to respect the inalienable right and duty of parents to provide, according to their means, for the religious and moral, intellectual, physical and social education of their children,"while section 2 provides:—"Parents shall be free to provide this education in their homes or in private schools or in schools recognised or established by the State." It was urged by Mr. MacBride that the word "education" in this Article should be given a wide meaning so that it would include rearing and nurturing and he went on to submit that the addition of the fluoride ion to the public water supply will therefore be an interference with the right of the parents to educate their children. The word "education" undoubtedly had this wide meaning at one time but in 1937, when the Constitution was enacted, it had become obsolete. In the

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 Shorter Oxford Dictionary, issued in 1933, the meanings given for the word "education" are:—"(1) the process of nourishing or rearing" (this is marked with a sign to show that this meaning was obsolete in 1933) "(2) the process of bringing up young persons (3) the systematic instruction, schooling or training given to the young (and, by extension, to adults) in preparation for the work of life. Also the whole course of scholastic instruction which a person has received."In other dictionaries the meaning for which Mr. MacBride contends is also described as obsolete. Moreover, it seems to me that the terms of the Article show that the word "education"was not used in this wide sense in the Constitution. Section 1 of the Article recognises the "right and duty of parents to provide, according to their means, for the religious and moral, intellectual, physical and social education of their children," but in section 2 it is provided that the parents are free to provide this education in their homes or in schools recognised or established by the State. The education referred to in section 1 must, therefore, be one that can be provided in schools and must, therefore, be one of a scholastic nature. It seems to me, therefore, that the fluoridation of the public water supply (even if it be harmful) does not interfere with or violate the rights given to the family and to the parents by Article 42 of the Constitution. It was agreed during the argument that the puzzling contrast between the family and the parents in section 1 of Article 42 was not relevant to any of the issues in this case.
 The third branch of the plaintiff's case is based on Article 40, 3, of the Constitution. Article 40 is the first of the Articles in the part of the Constitution which is headed, "Fundamental Rights," and Article 40 is headed, "Personal Rights."The arrangement of the sections in this Article (in many ways the most important in the Constitution, for Article 5 declares that Ireland is a democratic State and what can be more important in such a State than the personal rights of the citizens) presents some problems. Section 1 gives equality before the law to all citizens as human persons. Section 2 provides that titles of nobility shall not be conferred by the State. Section 3, sub-s. 1, provides that the State guarantees in its laws to respect, and, as far as practicable, by its laws to defend and vindicate the personal rights of the citizen, while sub-s. 2 of that section provides:—"The State shall, in particular, by its laws protect as best it may from unjust attack and, in the case of injustice done, vindicate the life, person, good name, and property rights of every citizen."Section 4 gives the right to personal liberty. Section 5 deals with the inviolability of the dwelling-house, while in section 6 the State guarantees liberty for the exercise

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 of the rights of freedom of expression for convictions and opinions, of peaceful assembly and the right to form associations and unions. Whatever may be the extent of the general guarantee given by section 3 for personal rights, it is difficult to understand why it was inserted between the right to equality before the law and the other specified personal rights.
 The first matter to be considered on this general guarantee is whether the High Court has jurisdiction to declare an Act of the Oireachtas unconstitutional because, in the opinion of that Court, it is a breach of the guarantee by the State "in its laws to respect, and, as far as practicable, by its laws to defend and vindicate the personal rights of the citizen." I have to anticipate a later part of this judgment by saying that, in my opinion, this general guarantee relates not only to the personal rights specified in Article 40 but to those specified personal rights and other personal rights of the citizen which have to be formulated and defined by the High Court. In the course of his argument the Attorney General conceded that the High Court had jurisdiction to declare an Act of the Oireachtas invalid if it did not respect, and, as far as practicable, defend and vindicate the personal rights of the citizen and if, in addition, the Oireachtas had acted oppressively or in bad faith in passing the Act; but when Mr. William Finlay was making the closing speech on behalf of the Attorney General, he referred in another context to a passage in the advice given to the President by the Supreme Court in relation to the constitutional validity of the Offences Against the State (Amendment) Bill, 1940, from which it would appear that a majority of that Court were of opinion that the High Court and Supreme Court had no jurisdiction to declare an Act of the Oireachtas unconstitutional because it was a violation of the general guarantee in section 3: see  In re Art. 26 of the Constitution and the Offences Against the State (Amendment) Bill, 1940 (1). The passage (at p. 481) is:—"Article 40 deals with personal rights. Clause 3 thereof provides that the State guarantees by its laws to respect, and, as far as practicable, by its laws to defend and vindicate the personal rights of the citizen, and to protect from unjust attack and, in case of injustice done, to vindicate, the life, person, good name, and property rights of every citizen. It is alleged that the provisions of the Bill are repugnant to the guarantee contained in this clause. It seems to us impossible to accede to this argument. The guarantee in the clause is not in respect of any particular citizen, or class of citizens, but extends to all the citizens of the State, and the 

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 duty of determining the extent to which the rights of any particular citizen, or class of citizens, can properly be harmonised with the rights of the citizens as a whole seems to us to be a matter which is peculiarly within the province of the Oireachtas, and any attempt by this Court to control the Oireachtas in the exercise of this function, would, in our opinion, be a usurpation of its authority."
 If it be assumed that advice given by the Supreme Court to the President binds the High Court in the same way as does a decision of the Supreme Court in a case between parties (and my view is that it does not), the passage does not bind me to hold that the High Court has not jurisdiction to consider the validity of an Act of the Oireachtas when it is claimed that it is a violation of the general guarantee in section 3 of Article 40, because the passage is wholly irreconcilable with the later judgment of the Supreme Court in  In re Philip Clarke (1). In that case Mr. Justice O'Byrne when delivering the judgment of the Court said (at p. 247) in relation to the passage I have quoted in the advice of the Supreme Court:—"A passage, at p. 481, in the judgment delivered by Sullivan C. J. in  In re Art. 26 of the Constitution and the Offences Against the State (Amendment) Bill, 1940 (2) was relied upon as laying down the proposition that the Court could not consider whether a guarantee contained in the Constitution has been infringed by an Act of the Oireachtas. Such an interpretation of the passage would be inconsistent with the principle already referred to as having been laid down in that judgment. The passage must be read as a rule of prudence in the consideration of the question of express or implied repugnance, especially in matters such as those involved in the said Bill."
 In my opinion, the High Court has jurisdiction to consider whether an Act of the Oireachtas respects and, as far as practicable, defends and vindicates the personal rights of the citizen and to declare the legislation unconstitutional if it does not. I think that the personal rights which may be involved to invalidate legislation are not confined to those specified in Article 40 but include all those rights which result from the Christian and democratic nature of the State. It is, however, a jurisdiction to be exercised with caution. None of the personal rights of the citizen are unlimited: their exercise may be regulated by the Oireachtas when the common good requires this. When dealing with controversial social, economic and medical matters on which it is notorious views change from generation to generation, the Oireachtas has to reconcile the exercise of personal rights with the claims 

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 of the common good and its decision on the reconciliation should prevail unless it was oppressive to all or some of the citizens or unless there is no reasonable proportion between the benefit which the legislation will confer on the citizens or a substantial body of them and the interference with the personal rights of the citizen. Moreover, the presumption that every Act of the Oireachtas is constitutional until the contrary is clearly established applies with particular force to this type of legislation.
 The next matter to be considered (though I have already said something about it) is whether the general guarantee in Article 40, section 3, relates only to those personal rights which are specified in Article 40 or whether it extends to other unspecified personal rights of the citizen. If it extends to personal rights other than those specified in Article 40, the High Court and the Supreme Court have the difficult and responsible duty of ascertaining and declaring what are the personal rights of the citizen which are guaranteed by the Constitution. In modern times this would seem to be a function of the legislative rather than of the judicial power but it was done by the Courts in the formative period of the Common Law and there is no reason why they should not do it now. A number of factors indicate that the guarantee is not confined to the rights specified in Article 40 but extends to other personal rights of the citizen. Firstly, there is sub-s. 2 of section 3 of Article 40. It reads:—"The State shall, in particular, by its laws protect as best it may from unjust attack and, in the case of injustice done, vindicate the life, person, good name, and property rights of every citizen." The words "in particular" show that sub-s. 2 is a detailed statement of something which is already contained in sub-s. 1 which is the general guarantee. But sub-s. 2 refers to rights in connection with life and good name and there are no rights in connection with these two matters specified in Article 40. It follows, I think, that the general guarantee in sub-s. 1 must extend to rights not specified in Article 40. Secondly, there are many personal rights of the citizen which follow from the Christian and democratic nature of the State which are not mentioned in Article 40 at all—the right to free movement within the State and the right to marry are examples of this. This also leads to the conclusion that the general guarantee extends to rights not specified in Article 40.
 In my opinion, one of the personal rights of the citizen protected by the general guarantee is the right to bodily integrity. I understand the right to bodily integrity to mean that no mutilation of the body or any of its members

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 may be carried out on any citizen under authority of the law except for the good of the whole body and that no process which is or may, as a matter of probability, be dangerous or harmful to the life or health of the citizens or any of them may be imposed (in the sense of being made compulsory) by an Act of the Oireachtas. This conclusion, that there is a right of bodily integrity, gets support from a passage in the Encyclical Letter, "Peace on Earth":—"Beginning our discussion of the rights of man, we see that every man has the right to life, to bodily integrity and to the means which are necessary and suitable for the proper development of life; these are primarily food, clothing, shelter, rest, medical care, and finally the necessary social services." If then the Act of 1960 imposes the consumption of fluoridated water on the citizens and if that is or may, as a matter of probability, be dangerous or harmful to the life or health of any of the citizens, the plaintiff's right to bodily integrity would be infringed and the legislation would be unconstitutional.
 At an early stage in this case the Attorney General submitted that I should not hear evidence that the fluoridation of water was dangerous. He argued that the jurisdiction to declare an Act unconstitutional on the ground that it did not respect the personal rights of the citizen could be exercised only if the Act were oppressive or had been enacted in bad faith and that this had not been pleaded. The plaintiff has, however, pleaded that the fluoridation of the public piped water supply will be dangerous. The Attorney General also relied on the fact that when the Oireachtas was considering the Act of 1960, they had before them the report of the Fluorine Consultative Council who advised that the fluoridation of the public water supply at a concentration of 1 p.p.m. was not dangerous; he said that this established that the Oireachtas was not acting in bad faith or oppressively when enacting the Act of 1960. I decided to admit the evidence because a plea that the fluoridation of the public water supply involves an element of danger seemed to me to be a plea that the Oireachtas had not respected the rights of the citizen to life and to bodily integrity. Moreover, it seemed to me that a plea that the process was dangerous involved a charge that the Oireachtas had acted oppressively, for a medical process which might be dangerous would, if imposed on the citizens, be oppressive.
 The next issue to be considered is whether the fluoridation of the public water supplies, even if it be dangerous, is a violation of the plaintiff's right to bodily integrity. In my opinion, it is not. The plaintiff has no legal right to a supply of piped water and the Act of 1960 does not impose any

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 obligation on her or on the members of her family to drink or use the water coming through the piped water supply. True that water to-day is a necessity of life and that the plaintiff probably has a right of access to a supply of water, but this does not give her a right to a supply of water which has not been fluoridated through the piped water supply. On this ground alone the case fails. Moreover, I am satisfied that the plaintiff and any of the citizens of the State can, by the expenditure of a few pounds, remove all or almost all the fluoride ions from the water coming through the piped water supply. I accept all the evidence of Dr. Fremlin on this aspect of the case.
 It may be, however, that this approach is too legalistic or too narrow and because of this and because of the great volume of evidence which has been given about the risks said to be involved in fluoridating water, I propose to consider whether the fluoridation of the public water supply is or may be dangerous to the citizens of this State or to some of them. On this aspect of the case many distinguished witnesses have given evidence and I would like to thank them for the care which they gave to the preparation of their evidence and for the way in which they ransacked the great volume of literature on the subject so that they could bring before the Court anything in any language that would be of assistance. A special word of thanks is due to Professor Hodge who was in the witness box for six days and who gave his evidence with unfailing courtesy and in non-technical language. I would also like to pay tribute to Mr. MacBride, leading counsel for the plaintiff, who took upon himself almost the entire burden of the plaintiff's case, who had steeped himself in the literature on the subject and who cross-examined the witnesses for the defendant with skill and persistence.
 The opponents of the fluoridation of the public water supply constantly use the words "poison," "toxic" and "toxicity."They say that a high concentration of the fluoride ion is poisonous and toxic. Evidence was given in this case to establish that a high concentration of the fluoride ion is toxic and it was then suggested that any introduction of the fluoride ion into water must therefore involve an element of risk to health. This, however, begs the whole question for many substances used in modern medicine are, when taken at a sufficiently high degree of concentration or in considerable numbers, poisonous and even lethal. A layman knows that arsenic and strychnine are used in medicine today and also knows that these can be poisonous: even the harmless and beneficial aspirin when taken in sufficient numbers can have fatal results.
 Having heard the evidence and read the literature which

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 it was agreed I should read, I am satisfied that the fluoridation of the public water supplies at the concentration of 1 p.p.m. will not, in our temperate climate, be dangerous to anybody, old, young, healthy or sick. I am also satisfied that there is no reasonable possibility that it may involve an element of danger or risk to life or health to any of the citizens of this country.
 It would, I think, be sufficient for the purposes of this case to say that the plaintiff has not proved that the fluoridation of the public water supply is dangerous but I do not think that I should so confine myself. The evidence given on behalf of the plaintiff at the earlier stages in this case received wide publicity while the far more compelling evidence for the defendant received little public notice. It is possible that the evidence for the plaintiff, some of which was of a sensational character, may have created public uneasiness. Let me say then that I am satisfied beyond the slightest doubt that the fluoridation of the public water supplies in this country at a concentration of 1 p.p.m. will not cause any damage or injury to the health of anybody, young, old, healthy or sick, who is living in this country and that there is no risk or prospect whatever that it will. The evidence on which I base this view consists of a number of separate items each of which is conclusive; when taken together, they are overwhelming.
 Firstly, 44 million people living in urban areas in the United States of America are now receiving fluoridated water at a concentration of 1 p.p.m. The process of fluoridating water has been going on for 17 or 18 years in the United States of America and there is no trustworthy evidence whatever that it has caused any symptoms of damage or injury to health. Secondly, there is the evidence provided by the observations in Newburgh and Kingston and in Bartlett. Thirdly, there are the results of the careful observations made in Anglesey. Fourthly, there is the testimony of all the reports of the official commissions which have studied the matter: the members of all of them were unanimously of opinion that the fluoridation of the public water supply was safe. Lastly, there is the evidence in this case.
 I have already referred to the striking reduction in the rate of dental decay in children which was produced by the fluoridation of the public water supplies in Newburgh. In 1945 the public water supply of Newburgh was fluoridated to bring the concentration of the fluoride ion in that water up to 1.0/1.2 p.p.m. and in 1955 and subsequent years, most careful examinations of the health of the children in Newburgh were carried out. I accept the whole of the evidence of Professor Hodge and of Dr. Schlesinger about these examinations.

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 The results were summarised in an article written by Professors Hodge and Smith in the publication called "Fluoridation as a Public Health Measure" to which I have already referred. The title of the article is "Some Public Health Aspects of Water Fluoridation" and it contains this passage (at p. 98) under the heading, "Health of populations drinking fluoride-containing water":—"The Newburgh Kingston Study. The body of information that bears most acutely on the safety of water fluoridation at 1 p.p.m. is being assembled in the Newburgh-Kingston Caries Fluorine Study (see elsewhere in this volume). Since May 1945, the water supply of the city of Newburgh, New York, has been treated to bring its fluoride content up to approximately 1.1 p.p.m. The water supply of the companion city of Kingston has remained fluoride-free. As Schlesinger, Overton and Chase pointed out in 1950 'Before any public health procedure can be recommended for routine use, every effort should be made, within limits of available techniques, to ascertain the safety of the procedure in question. Although there is no acceptable evidence that naturally occurring fluoride in the concentration used in drinking water as a caries-deterrent exerts any deleterious systemic effects, it is desirable to make carefully controlled observations of children receiving fluoride introduced into their drinking water, especially while it is still possible to do so before public clamour for routine use of fluoride precludes control study."
 "More than 500 children in each city have been selected for study. The ages range from 1.5 to 12 years; most of the age groups comprise 30 to 60 children. In addition, during each of the first three years a group of infants less than one year old were enrolled. Some selection was made to get children from families that probably will remain in the city for the duration of the study. Because the examinations were voluntary, matching of groups for such factors as socio-economic status was not entirely successful. A research team conducts medical examinations in both cities led by a pediatrician who directs the public health nurse, laboratory technician and clerk receptionist. The medical examinations are given annually; in addition to the customary measurements and history, the physical examination pays special attention to tissues and organs that have been mentioned as sensitive to higher doses of fluoride, for example, skin, hair, nails, the formed elements of the blood, and the structure of the bone. Records are made, for example, whether the nails are normal or whether longitudinal striations or white marks are present. The skin is observed to see whether abnormal moisture, texture, colour or any other eruptions are present. A special group of 25

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 children of various ages in Newburgh has been given eye and ear examinations; the visual acuity is measured, visual fields are mapped, and audiometer tests are given.
 The results of this impressive list of careful and controlled examinations give to date a completely clean bill of health to water fluoridation under the conditions of this test. The children of the two cities are alike in height and weight. The blood picture is normal, urine analyses are negative, the condition of nails, skin, and hair is entirely comparable, the results of the eye and ear examination are typical. The most convincing single similarity of observation probably comes from the X-ray examinations. Films are taken of the right wrist and both knees of each child annually. These are read 'blind' by Dr. John Coffey, professor of clinical pediatrics, Columbia University; he has 'found no detectable difference in bone density in children in the two cities studied. Dr. Coffey also found both groups of children to be in the normal range of skeletal maturation on clinical estimation.'
 In a preliminary report the results so far are summarised in these words: 'No deleterious systemic effects from the ingestion of fluoride in drinking water in the doses employed.' Since many of the questions most frequently asked about fluoride involve lengthy periods (for example enamel mottling arises in the first eight years of life during which enamel formation occurs), even a survey of four or five years work must be qualified. The authors take a conservative stand. 'It must be emphasised, however, that a longer period of observation is required before final conclusions can be drawn. The possibility of demonstrating cumulative effects of fluoride in the final years of the ten years study cannot be eliminated at this time'."
 Even more compelling is the evidence supplied by the examinations of persons in the towns of Bartlett and Cameron in Texas. The concentration of the fluoride ion in the water there is 8.0 p.p.m.: the control taken was Cameron, Texas, where the concentration is 0.4 p.p.m. The results of this study are summarised on page 358 of a publication called "Fluoride Drinking Waters," issued by the United States Department of Health, Education and Welfare. I have heard evidence about the Bartlett/Cameron study and I accept this summary as being correct. The passage is:—"The Bartlett/Cameron Study. A comprehensive survey has been made of the health of persons exposed to 8.0 p.p.m. of fluoride present in the water in Bartlett, Texas, compared to a similar group of individuals exposed to 0.4 p.p.m. fluoride in the drinking water of Cameron, Texas. The participants resided in these two towns for at least 15 years when first examined in 1943.

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 The second examination was made in 1953. Included in this investigation was a full medical history, physical, dental and X-ray examination and detailed urine and blood analysis. There was no tendency towards higher rates in these two population groups in respect to specific systemic abnormalities or laboratory findings excepting a higher incidence of dental fluorosis in Bartlett (8.0 p.p.m. fluoride). The difference between the age-corrected death rates of the two groups was not statistically significant. Thus, no clinically significant physiologic or functional effects could be attributed to a prolonged ingestion of drinking water containing as much as 8.0 p.p.m. of fluoride. With regard to deleterious bone changes none were produced by ingestion of this high fluoride water. There was no unusual incidence of bone fractures, arthritis, hypertrophic bone changes or exostoses or interference with fracture healing. There were no cases of 'poker spine' and no associated functional or systemic effects. It may be noted that the excessive fluoride in this water supply did produce roentgenographic evidence of bone changes in 10 to 15 per cent of the Bartlett population group. However, these changes were slight, often difficult to recognise and frequently equivocal in degree."
 Similar results were obtained from studies in Colorado Springs, Colorado, where the concentration of the fluoride ion is 2.5 p.p.m. The results of studies in that city are summarised on page 359 of the same publication.
 Similar results, both in the reduction of dental caries among children by the introduction of fluoridation and the absence of any injury to health, were found in Anglesey and I accept the whole of the evidence of Dr. Wynn Griffiths, who gave evidence about them. The results will be found summarised in a publication called "The Conduct of the Fluoridation Studies in the United Kingdom and the Results Achieved after Five Years" issued by the Ministry of Health. Some of the passages which are particularly relevant are:—"Anglesey is mainly agricultural in character with some 50,000 population. Holyhead, the largest town, has a population of 10,000. The water is soft and the water supply for the whole county except Holyhead comes from one source. There are, however, two pumping stations, one of which serves the Gwalchmai zone and the other the Bodafon zone. Fluoride was added to the water pumped to the Gwalchmai water but not to that for the Bodafon zone. Holyhead receives most of its supply from the pumping station serving the Gwalchmai zone but at times of heavy demand needs to take additional supplies from a secondary station. It was not practical to add fluoride to the supply from a secondary station; consequently the level of

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 fluoride in the water reaching Holyhead has varied according to the extent to which it contained water from the unfluoridated source."
 "The data showing the effects of fluoridation are those for the base-line years and those for 1961, that is 52 years after fluoridation began in the Gwalchmai zone at Anglesey and in Holyhead. In the study area of . . . the Gwalchmai zone at Anglesey, the extent of dental decay as measured by the average number of carious teeth per child, has been markedly reduced in the younger age groups both absolutely and by comparison with the other areas. The proportion of children free from caries has been substantially increased and the proportion of children with ten or more carious teeth has been greatly reduced. There has also been a substantial improvement in the dental health of the children living in Holyhead although, for reasons explained earlier in this report, the level of fluoride in Holyhead has been variable."
 The conclusions in relation to the effect of fluoridation on public health in the same publication are:—"(1) Five years of fluoridation at a level of 1 p.p.m. in three study areas has brought about in each a substantial improvement in the teeth of young children. (2) The results of fluoridation obtained so far are in line with American experience. (3) No evidence of harm from fluoridation has been discerned despite continuous vigilance. (4) The addition of fluoride to water supplies at a specified level has presented no technical difficulties."
 The reports of the Commissions which have studied the matter provide cogent evidence of the safety of water fluoridation. There is, in the first place, the report of the Irish Fluorine Consultative Council which recommended the fluoridation of public water supplies at a concentration of 1 p.p.m. It did not recommend that the process be made compulsory but thought that its adoption should be decided by each local authority; but the report of that most representative Council indicated that there was, in their view, no risk to health involved in the fluoridation of the public water supply. There is, in the second place, the report published in 1958 of the Expert Committee on Water Fluoridation set up by the World Health Organisation. The members were drawn from many countries and were very highly qualified; one of them, Professor Ericsson, gave evidence in this case and I accept the whole of his evidence. This Committee summarised their conclusions in these terms:—
 "1. Dental caries is one of the most widespread and prevalent diseases.
 2. There is no hope of controlling the disease by present treatment methods alone.

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 3. Among the numerous preventative methods, fluoridation of drinking-water supplies is the most promising.
 4. The effectiveness, safety and practicability of fluoridation as a caries-preventative measure has been established.
 5. 1 p.p.m. fluoride has been shown to give maximum benefits; first by epidemiological studies where fluoride occurs naturally in the water and secondly, where fluoride has been added at optimum concentration through mechanical means.
 6. Hundreds of controlled fluoridation programmes are now in operation in many countries. Some have been in progress for the past 12 years, so that conclusions are based on experience. No other public health procedure, during the initial stages of its application, has had such a background in time or extent.
 7. The biological effects of fluoride have been described in nearly 3,000 clinical and experimental reports in the past 20 years. This literature is not only extensive but of broad scope.
 8. Fluoride penetrates cells and in sufficiently high concentrations inhibits certain enzymes, but no evidence of enzymal inhibition has been found in persons drinking fluoridated water containing concentrations of fluoride optima for dental health.
 9. Most of the fluoride absorbed into the system is rapidly excreted, principally in the urine; the rest is deposited in the minerals of the bones and teeth.
 10. When large doses or excessive amounts of fluorides are ingested for protracted periods (many years), the skeletal system exhibits structural changes. The clinical manifestations are classed (a) crippling fluorosis (20/80 mg. of fluoride or more per day for 10 to 20 years; calcification changes in bone together with calcification of ligaments); (b) asymptomatic osteosclerosis (more than 5 mg./1 of urine excreted daily for 5 to 10 years; hypercalcification in one or more bones without disability); and (c) mottled enamel (drinking water containing 2 to 8 p.p.m. fluoride or more during the first 8 years of life; interference with enamel formation, stained or in severe cases irregular enamel surfaces). Adequate factors of safety guarantee the absence of these changes when water containing 1 p.p.m. fluoride is drunk.
 11. Toxic doses of fluorides (50 times that used in controlled water fluoridation) injure the kidneys. There is no evidence of kidney injury or any effect on concurrent kidney disease in the

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 populations drinking fluoridated water where fluoride concentrations range up to 5 p.p.m.
 12. No relation between thyroid disfunction and naturally fluoridated water has been established. In animal studies, daily doses in excess of 50 p.p.m. in the diet produced structural and functional changes in the thyroid. In humans, drinking water containing 1/5 p.p.m. is without demonstrable effect on the thyroid.
 13. Growth and development, somatic and psychic, are normal in children drinking water containing 1 p.p.m. fluoride.
 14. The formation of teeth and even their resistance to caries and their appearance are improved when water containing optima concentrations of fluoride is consumed.
 15. Over 3 million people in the U.S.A., over half a million in England, and large population groups in other countries have, during their lifetime, consumed water containing 1 p.p.m. fluoride or more. Mortality and morbidity rates for five leading causes of death are comparable for cities in the U.S.A. with fluoride and non-fluoride public water supplies. No relation between fluoride and arthritic changes in bone has been found, nor have confirmed cases of allergy to water containing 1 p.p.m. fluoride been described.
 16. The addition of fluorides to public water supplies has proved to be similar to other routine mechanical procedures widely employed in waterwork practice. Suitable equipment has been developed, reliable analytical procedures are available, and appropriate safeguards have been established.
 17. No other vehicles or techniques for the prophylactic application of fluorides can at present replace the fluoridation of drinking water as a public health measure. Where water fluoridation cannot be used, research into other vehicles and improved methods of local fluoride application should, however, be encouraged.
Conclusions
 1. Drinking water containing about 1 p.p.m. fluoride has a marked caries-preventive action. Maximum benefits are conferred if such water is consumed throughout life.
 2. There is no evidence that the water containing this concentration of fluoride impairs the general health."
 "3. Controlled fluoridation of drinking water is a practicable and effective public health measure."
 Then there is the report of the Committee set up in Ontario to report on water fluoridation as a public health measure. The members carried out a most extensive examination of the

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 evidence and of the literature and heard many witnesses who were opposed to fluoridation. They recommended water fluoridation and reported that there was no risk to public health involved in it. There is also the report of the Commission in New Zealand; it was set up to consider the fluoridation of water supplies as a public health measure and reported in its favour. This report was impugned by some of the witnesses for the plaintiff in this case; one of them said that the members of the Committee did not include a biochemist and another said that he did not think that a Judge of the High Court in New Zealand was a suitable chairman! Lastly, there is the statement on the fluoridation of public water supplies by the House of Delegates of the American Medical Association. The American Medical Association is a most representative body of the medical profession in the United States of America and the House of Delegates of that Association recommended fluoridation of the public water supplies at a concentration of 1 p.p.m.
 I come now to deal with the evidence in this case. I accept the whole of the evidence given by Professors Hodge and Ericsson and by Dr. Galligan. Both Professor Hodge and Dr. Galligan were in the witness box for six days and were cross-examined at considerable length on the literature on this subject. In the course of cross-examination Dr. Galligan was accused of perpetrating a scientific fraud in one of the articles which he wrote; I am satisfied that he completely vindicated himself of this charge. I also accept the evidence of Dr. Schlesinger, Dr. Arnold, Dr. Armstrong and Dr. Dirk. If their evidence in any way contradicts that of Professors Hodge and Ericsson or that of Dr. Galligan, I prefer the evidence of Professors Hodge and Ericsson and Dr. Galligan. I reject the evidence of Professor Gordenoff, of Dr. Rozeik, of Dr. Waldboff and of Dr. Dillon. There was a marked note of fanaticism and passionate conviction about their evidence. I got the impression that they were determined at all costs to make a case against fluoridation. Typical of this was the evidence of Professor Gordenoff. He was asked in cross-examination whether he thought that the fluoridation of public water supplies would reduce the incidence of dental caries; his guarded answer was "perhaps," although his own writings showed that he held the view that it would. The plaintiff's witnesses (except Professor Steyn) also had a habit of prefacing their more sensational charges with the words"it has been suggested," without giving any authority for the suggestion or indicating its source (the evidence in connection with the distressing condition of mongolism in children was a particularly glaring instance of this). There is absolutely no

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 support in the literature or in the evidence for many of these suggestions.
 The evidence of Professor Benagiano and Dr. Fiorentini was based almost entirely on observations in the towns of Campagnano di Roma, Cesano, Bracciano, Anguillara and Castel Nuovo, all of which are near Rome. These observations suggest that there is a relationship between the presence of the fluoride ion in the drinking water and a high incidence of goitre together with an unusual basic metabolic rate. These observations and the conclusions drawn from them by Professor Benagiano and Dr. Fiorentini are not, in my opinion, reliable. There are a number of reasons for this. The first is the utter uncertainty about the amount and the concentration of the fluoride ion in the waters in these towns. At an early stage in the case both these witnesses said that the concentration of the fluoride ion in the water in these areas was approximately 3.5 p.p.m., but when Dr. Fiorentini was recalled on Mr. MacBride's application on the 64th day of the trial, he said that the concentration was 0.6 to 1.73 p.p.m. or 0.61/1.73 mg. per litre. This startling change may well have been caused by the confusion about sodium fluoride and the concentration of the fluoride ion which it gives: it will be recalled that 98 per cent sodium fluoride by weight gives 44 per cent available fluoride ion, but if there was a confusion, it was in the minds of Professor Benagiano and Dr. Fiorentini and was a circumstance which they should have investigated before they gave evidence about these observations. The observations are also open to criticism because there was no control. A control is an essential part of any public health experiment and observation; it is got by taking an area similar in all respects except the presence of the element under investigation and then comparing the results. There was, however, no control for Campagnano and the other Italian towns. I am not satisfied that the higher goitre incidence in these towns has any connection with the fluoride ion in the water or its concentration. The unusual degree of mottling of the tooth enamel found there is, I think, principally the result of malnutrition (see Massler and Schour, "Relation of Endemic Dental Fluorosis to Malnutrition," in the Journal of the American Dental Association for February, 1952). I also reject the results of these observations in Italy because they are inconsistent with the results of the observations made in the United States of America where the examinations were more thorough and were carried out under ideal conditions.
 Professor Steyn, who came from the Union of South Africa to give evidence, was a most impressive witness. He said that the preponderance of evidence was that the fluorine, as he

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 called it, builds up the tooth enamel and makes it caries-resistant; he remarked that he agreed with this view. In his opinion caries is the most serious disease of our civilisation not merely because it causes bad teeth but because bad teeth run down the human system and he thought it desirable that modern society should take steps to deal with it. He favoured the use of fluorine in the battle against dental decay but thought it should be used topically, that is by application, and that it should not be put into the water supply. He also said that at a concentration of 1 p.p.m. fluorine does not produce severe mottling of the teeth. His objection to the use of fluoride ion in the water supply was that he thought that there was a connection, in the Union of South Africa at least, between the presence of the fluoride ion in water and a high incidence of goitre. I do not accept the view that the presence of the fluoride ion in water at a concentration of 1 p.p.m. will produce goitre in anybody: it seems to me more likely that the high incidence of goitre in many parts of the Union of South Africa is caused by iodine deficiency. I think that the Newburgh-Kingston observations show that the fluoride ion at a concentration of 1 p.p.m. or even higher does not cause goitre in any of those who drink water containing that concentration.
 Dr. Sinclair, a Fellow of Magdalen College, gave evidence for the plaintiff: most of his evidence was a statement of what may happen if the fluoride ion is introduced into water. He conceded during cross-examination that many of the ill-effects which he mentioned would not arise when the concentration of the fluoride ion in water was 1 p.p.m. I do not think that any of his evidence supports the view that the fluoridation of the public water supplies at this concentration is dangerous or that there is a reasonable possibility that it may be dangerous. If any of his evidence supports this view, I reject it.
 I propose now to deal with the principal ill-effects which, it is said, will be produced by the introduction of the fluoride ion into the public water system.
 The first complaint is that the fluoride ion in water will have an ill-effect on the skeleton. Some of the fluoride ion ingested is deposited in the skeleton and some is excreted; about one-third to one-half of the fluoride ion ingested is deposited quickly in the skeleton and is thereby taken out of circulation in the human body. The evidence establishes that large doses of the fluoride ion are capable of producing simultaneously the conditions known as osteosclerosis (which is a thickening of the bone) and osteoporosis (which is a thinning of the bone). When the water contains the fluoride ion

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 at a concentration of less than 5 p.p.m. there is no evidence that any skeletal changes except an increased deposit of the fluoride ion in the bones can be seen by X-ray or otherwise. When the water contains less than 5 p.p.m. of the ion, the evidence is coercive that it does not cause any osteosclerosis or osteoporosis. At a concentration of 5 p.p.m. when there has been ingestion of fluoridated water over a long period, osteosclerosis does, in exceptional cases, occur as a result, but in most cases a concentration of 8 p.p.m. is required to do this. A person ingesting water with very little of the fluoride ion in it for seventy years would, at that age, have a concentration of approximately 1,500 p.p.m. of the fluoride ion in his bones. If it is assumed that one-third to one-half of the fluoride ion ingested is deposited in the skeleton (and I think that the evidence supports this view,) a person aged seventy who had been drinking water fluoridated at a concentration of 1 p.p.m. all his life would have a concentration of about 4,000 p.p.m. of the fluoride ion in his skeleton at that age. I am satisfied that this concentration of 4,000 p.p.m. does not produce any harmful results and does not involve any hazard. This is confirmed by the animal studies which were described in great detail in this case. In some of these, water with a concentration of 50 p.p.m. of the fluoride ion was given for seven months to pigs and for eleven months to dogs and no skeletal changes were found at the end of those periods. The evidence also establishes that the deposition of the fluoride ion increases with age so that the bone samples taken from old people show an increased concentration of it caused by the presence of the fluoride ion in water. I am satisfied that a concentration of 1 p.p.m. of the fluoride ion in the water, though it produces an increase in the concentration of the ion in the bone by a gradual process, does not involve any risk of damage to life or health for anybody, young or old.
 The next ground of complaint against the introduction of the fluoride ion into drinking-water is that it causes mottled enamel or hypoplasia. The existence of this originally led public health officers and dentists to investigate the effect of the fluoride ion on teeth. A high concentration of the fluoride ion in drinking water causes disfiguring mottled enamel, but also greater resistance to dental decay. If the water in Ireland is fluoridated to a concentration of 1 p.p.m., ten per cent of the children will develop mild, and very mild mottling of their teeth. Dr. Galligan distinguished between disfiguring mottling and mild and very mild mottling. I accept the view that the mottling of the teeth of ten per cent of the children in Ireland will not be an indication of fluorosis or of any damage or harm having been done to the children's

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 teeth by the fluoride ion in the water which they have drunk. This mild and very mild mottling is not a condition which will be perceptible by most people; indeed, Dr. Galligan suggested that mild and very mild mottling might improve the appearance of the teeth. I am, however, satisfied that the mild and very mild mottling which will be produced in the teeth of some children is not an indication of any element of risk to health or of dental harm or damage to any of the children who get it.
 Another ground of objection to the introduction of the fluoride ion into the drinking-water is that it would or might cause goitre or other thyroid conditions. The suggestion is that the fluoride ingested affects the functioning of the thyroid gland. I am satisfied that it does not. The basis for the view that it does is the assumption that there is an antagonism between the fluoride ion and iodine so that the fluoride ion will absorb the iodine which is in the human body or which is acquired from food and water. In my opinion, there is no antagonism between fluoride and iodine. The most probable cause of goitre is iodine deficiency: this is illustrated by the evidence given by Professor De Mole who described the significant reduction in the incidence of goitre in Switzerland when people were persuaded to take iodine tablets. He added that the incidence of goitre fell dramatically when iodine tablets had been taken and he said that before they were made available the inhabitants of some areas in Switzerland laughed at those from outside because of their small necks. Moreover, I think that the observations in the United States of America show conclusively that there is no connection between goitre and the ingestion of the fluoride ion.
 Yet a further ground of objection to the introduction of the fluoride ion into drinking-water is based on its effect on enzymes. This is a highly technical matter; the witnesses were agreed that further research will be necessary before any firm conclusion can be drawn. I have not been able to find in the documents put in evidence any statement of what enzymes are, and when I asked Professor Hodge about this, he gave, in his usual very clear fashion, a description of their function. I propose to quote from his evidence:—"The events that go on in the human body are, from the standpoint of the chemist who works with a test-tube, a very improbable state of events. May I take as an example the fact that one of the chief sources of energy in the body is sugar; in the body sugar is converted into carbon dioxide and water by using some of the oxygen in the air which we breathe. A lump of sugar can sit on the table at room temperature or in the air in warm temperature without the slightest change although in contact with oxygen

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 of the air. In order to burn sugar a chemist heats it up and ultimately it will burn to give carbon dioxide and water. In the body this goes on at the temperature of 37C., which is the temperature we all have. To the chemist the burning of sugar at 37C. is extremely improbable. The body achieves this reaction which we call burning by the use of enzymes. The enzyme is able to bring about the interaction of the sugar and the oxygen and is described as a catalyst. The job of a catalyst is to speed a reaction without taking part in it. Enzymes are protein in nature and highly specialised so that many enzymes are involved in the process by which sugar is transformed into carbon dioxide and water releasing into the body energy which would be formed if sugar were burned in the air, so that it is a source of energy; this is done without the wasteful use of heat. The protein enzyme should be thought of as a surface and on it the sugar molecules settle into a space and there is an electrical charge arrangement which exactly complements in space and changes the sugar molecule so that it fits exactly on the protein enzyme surface. On this spot the first step in the changing of sugar into carbon dioxide and water occurs and this slightly altered sugar goes to the other sites until the process is completed. Enzymes make this improbable reaction possible, they give us energy and maintain life. There are some enzymes which could be inactivated without risk but there are other enzymes which if they cease to function would cause death." At a later stage in his evidence Professor Hodge remarked:—"We human beings are a very improbable organisation."
 It has been suggested by some of the plaintiff's witnesses that the ingestion of the fluoride ion will interfere with this enzymatic process. There is strong evidence that a high concentration of the fluoride ion interferes with the action of some enzymes but there is absolutely no evidence that a concentration of 1 p.p.m. or even of 2 or 3 p.p.m. will affect enzymatic action in any way; this conclusion gets support from the experiments on animals. In my opinion the evidence is coercive that a concentration of 1 p.p.m. will not affect enzymes or the enzymatic process in any way.
 It is also suggested in evidence that the fluoridation of water will affect kidney function. Undoubtedly, large doses of the fluoride ion or high concentrations of it are capable of causing injury to the kidneys, particularly in those who have a kidney disease, but there is no evidence whatever that a concentration of 1 p.p.m. will cause any damage or injury to the kidneys or to the kidney function of anybody, even of those who have a kidney disease.
 A further ground of objection to the introduction of the fluoride ion is that it will retard growth. There is no evidence

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 whatever that there has been any growth retardation in children who have taken water fluoridated to a concentration of 1 p.p.m. and the Newburgh/Kingston observations seem to me to be conclusive that the fluoride ion has not this effect. Animal experiments have been carried out in which high doses of the fluoride ion have been given and concentrations of 100 p.p.m. were required to produce some retardation in growth.
 Another ground of objection to the fluoridation of the drinking-water is that it may cause gingivitis and periodontal disease. The tissues which surround the teeth are called the gingiva: they are soft tissues and an infection which affects them produces a condition known as gingivitis. Periodontal disease, on the other hand, is one which affects the bony structure under the teeth (the periodontum is the bone underneath the teeth). The layman calls periodontal disease pyorrhoea. Dr. Galligan dealt fully with the suggested connection between the fluoride ion and gingivitis and periodontal disease and I accept his evidence. If one leaves out of consideration the observations made at Stratford, there is no evidence that there is any connection between the fluoride ion and gingivitis or periodontal disease; the high rate of periodontal disease found in Stratford is probably caused by poor oral hygiene. This topic of gingivitis is of interest in another connection. In a number of instances the witnesses for the plaintiff referred to articles by named authors to corroborate their views but, when I read the articles subsequently, they did not seem to me to support the views for which they were cited. The topic of gingivitis provided an example of this and also a most striking confirmation of Dr. Galligan's accuracy. When Professor Benagiano was giving evidence, he suggested that the fluoridation of the water supply could cause gingivitis and, in support of this, he referred to what he called "experiments" by Dr. Keith Box described in the Journal of the Ontario Dental Association for 1955. He said that Dr. Box's article was"a study" of an area where the water contained 1 p.p.m. fluoride and in which 79.2 per cent of the children had gingivitis. He also said that he had not read the article but that he had seen it summarised in Italy. Dr. Galligan gave evidence that he had searched through the Journal of the Ontario Dental Association for 1955, that there were no articles in it by Dr. Box but that there were two editorials in it written by Dr. Box which showed that he had not carried out the experiments or studies referred to but was commenting on studies carried out by others. That was the position when the evidence and speeches in this case concluded. I

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 subsequently discovered that in para. 120 of the New Zealand Commission Report, an article by Dr. Box is quoted in which he wrote in April, 1955:—"I have never made a survey of gingival and periodontal diseases in any areas where the water was naturally fluoridated . . . and I have written or published nothing on this subject."
 Some of the witnesses for the plaintiff suggested that the ingestion of the fluoride ion can affect the functioning and operation of the heart and reference was made to the writings of a Japanese scientist, Professor Takomori. There is, however, nothing in the evidence to suggest that the heart conditions which Professor Takomori found were in any way connected with the ingestion of the fluoride ion. I am not satisfied that any reliable conclusions applicable to Ireland can be drawn from the cases which Professor Takomori examined because of the great differences in climate and nutrition. It was also suggested that the fluoride ion affects mortality. The evidence from the United States of America is, however, conclusive that the ingestion of the fluoride ion at concentrations higher than 1 p.p.m. does not in any way affect the expectation of life of human beings.
 There are some suggestions in the literature that there is a connection between the ingestion of the fluoride ion and cancer: Mr. MacBride stated that the plaintiff was not suggesting this.
 The Ontario Committee in their report referred to a work by Elwell and Easlick, called "Classification and Appraisal of Objections to Fluoridation," and in para. 142 of the report a summary of the objections to fluoridation and the answers to the objections taken from that "monumental" work is quoted. I do not wish to lengthen this long judgment by quoting this exhaustive treatment of all possible objections to the fluoridation of water. It is enough to say that the authors and the members of the Committee conclude that none of the objections have any validity, a conclusion with which I respectfully agree.
 Moreover, I accept the evidence that there is in the human body what one of the doctors called "a homeostatic process."This is a kind of guard or balance by which the defences of the body go into action when anything in the body goes wrong: when the illness is serious, the homeostatic process is not strong enough to save life but if there were any cases where the fluoride ion might produce some ill-effects in the human body (I am not satisfied that there are) the homeostatic process would go into action and would counteract any harmful effects which might be produced.

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 It was also suggested that if the fluoride ion had to be taken, there were other methods available which did not involve any element of risk. This seems to me to be primarily a question for the Oireachtas. If it is accepted that the problem of dental caries has to be dealt with (and I think it imperative that it should be), water fluoridation seems to me to be the only practicable method. Fluorine tablets are not a practicable method for their administration requires a degree of persistence in parents which, unfortunately, does not exist. It is difficult enough to get children to take medicine when they are ill but it would be impossible, I think, to get them to take tablets regularly when they are well. The shortage of dentists makes the topical application of fluoride to the teeth impossible as a public health measure for all the children in the community.
 Throughout the case the plaintiff's counsel sought to establish that the fluoridation of water at a concentration of 1 p.p.m. involved "a dangerous dosage" of human beings with the fluoride ion. The first step in this argument was to establish what dose of the fluoride ion would be dangerous; the next step was an attempt to establish that the total amount of the fluoride ion taken in the food, in some drugs, and in the air, when added to the ingestion of water with a concentration of 1 p.p.m., would amount to a dangerous dose. Strong reliance was placed on the quantity of the ion which is in tea and also on the fact that when a kettle of water is allowed to boil, some of the water will evaporate while the ion will not and it was argued that this would cause an increase in the concentration of the fluoride ion. It was also submitted that the Oireachtas is not entitled to take a risk with the health of the citizens and that a concentration of 1 p.p.m. in the water would, when taken with the other sources of the fluoride ion, involve a risk. I am convinced that the amount of the fluoride ion ingested at a concentration of 1 p.p.m. in the water together with the amount of the ion in the food, in drink, in the air and in drugs (in so far as we know it) does not involve any element of danger or risk to health.
 There is some suggestion in the literature that the machinery which is used to put the fluoride ion into the water may be unreliable. This case was not made by the plaintiff. There is no evidence whatever that the machinery which will be used is unreliable. Even if it were, the daily check which the regulations make compulsory and the other check by the distillation method provide a complete safeguard against any risk from this.
 In my judgment, the fluoridation of the public water supplies in this country is not a violation of any of the plaintiff's constitutional rights and this action must be dismissed.

[1965]
1 I.R.	Ryan v. The Attorney General.
Kenny J.	332
Supreme Court.	

 From this judgment the plaintiff appealed to the Supreme Court (1).
Seán MacBride S.C. , T. J. Conolly S.C. , Seamus Egan S.C. and J. B. O'Quigley , for the appellant:—
 The appellant is aware that the putting of fluoride ions in the public water supply is intended to protect children against dental caries; nevertheless she considers this course unnecessary, in so far as her children are concerned, as both she and her husband, by attention to their children's diet and the discipline of their upbringing, have taken and continue to take adequate steps to protect them from this disease. She considers also that the addition of fluoride ions to the public water supply amounts to medication in the case of children, and she maintains that the right to decide what her children will eat and drink, together with all other aspects of their upbringing, is her function, and the policy of the law is not to interfere with the authority of the parents. She objects also as an individual, and maintains that this is an infringement of her own personal integrity. It is submitted that the Act invades these rights and is invalid as it is a violation of the authority of the family and of the imprescriptible rights guaranteed to the family by Art. 41 of the Constitution.
 The appellant submits that among the personal rights guaranteed to her and to her children by Art. 40, 3, 1 and 2, of the Constitution is a right to bodily integrity and any interference with bodily constitution without the consent of the person concerned constitutes an infringement of this right to bodily integrity.
 It is contended that the trial Judge's definition of "bodily integrity" is too narrow.
 The introduction of fluoride ions into the public water supply at a concentration of 1 p.p.m.F. will result in children or some of them suffering from some degree of mottling in their teeth and, furthermore, from the evidence adduced it would appear that a substantial proportion of the fluoride so administered will be deposited in or on the bones of persons drinking the water, thus altering the composition of their bones. It is contended that this process of fluoridating the public water supply amounts to mass medication. The administration of a chemical drug or other substance, which causes or threatens to cause any change from the normal and natural condition of the human body, is an interference with the right to bodily integrity. For these reasons it is submitted that the compulsory administration of fluoride in any form in the proportions permitted by this Act is an infringement 

[1965]
1 I.R.	Ryan v. The Attorney General.
Kenny J.	333
Supreme Court.	
 of the bodily integrity of the citizens and the Act is in this respect unconstitutional.
 It is also submitted that the Act is invalid on the grounds that it constitutes a violation of the inalienable right of the parents to provide for the physical education of their children and in this respect is contrary to Art. 42 of the Constitution. It is contended that the word "education" in this Article should be given a wide meaning and should be interpreted so as to include rearing and nurturing and this includes the provision of suitable food and drink for children. The addition of fluoride ions to the public water supply will, therefore, be an interference with the right of the parents to educate their children as provided by this Article. [They referred to  In re Art. 26 of the Constitution and the School Attendance Bill,1942 (1);  National Union of Railwaymen and Others v.Sullivan and Others (2);  The Lord Mayor, Aldermen, etc. of Dublin v. The Guardians of the Poor of the South Dublin Union (3);  Re Agar-Ellis, Agar-Ellis v. Lascelles (4);  In re  Ó Laighléis  (5); Waterworks Clauses Act, 1847 (10 ‡ 11 Vict., c.17); Dublin Corporation Waterworks Act, 1861 (24 & 25Vict., c. clxxii), ss. 43, 52, 88; Public Health Ireland Act, 1878 (41 & 42 Vict., c. 52), s. 65; Local Government (Sanitary Services) Act, 1948 (No. 3 of 1948), s. 20; Vanston's Public Health in Ireland (2nd ed.), p. 508.]
 At the conclusion of the argument on behalf of the appellant, the Chief Justice informed the Attorney General that the Court did not require to hear him on the evidence generally but rather on particular points arising out of the evidence which might be raised by members of the Court and on the Constitutional issues.
The Attorney General, W. D. Finlay S.C. , Seán Butler S.C. and J. Lovatt-Dolan  for the respondent:—
 It is generally agreed that dental caries is a serious disease. It is a world-wide problem and Ireland is no exception. The disease is general to the country but is found particularly in the City of Dublin. This is a problem that should be dealt with and, it is submitted, fluoridation is the best method of inhibiting dental caries and, from the evidence adduced, it is clear that there is no danger to health at the proposed concentration.
 It is conceded that the Court has jurisdiction to declare an Act of the Oireachtas invalid if it does not respect and, as far as practicable, defend and vindicate the personal rights 

[1965]
1 I.R.	Ryan v. The Attorney General.
Kenny J.	334
Supreme Court.	
 of the citizens and if, in addition, the Oireachtas has acted oppressively or in bad faith in passing the Act. When the Oireachtas was considering the proposed Act of 1960, they had before them the Report of the Fluorine Consultative Council which advised that fluoridation of the public water-supply at a concentration of 1 p.p.m. was not dangerous and, it is submitted, this established that the Oireachtas was not acting in bad faith or oppressively when enacting this legislation. The Act does not permit the Minister to do an act which would cause danger to the citizens. Before prescribing for the fluoridation of the public water supply it is necessary for him to have an analysis made of the water and, in pursuance of the statute, he must prescribe a definite proportion of fluoride ions to be added to the water subject to a maximum of 1 p.p.m. It is submitted that the Court may assume that the Minister will act in this respect in a reasonable manner and that he will permit the addition of fluoride ions only to a degree which is safe for the public health.
 The Court in considering Art. 41 of the Constitution may properly confine itself to section 1 of this Article and, it is submitted, this paragraph does not confer on parents unlimited rights. Furthermore, if the fluoridation of the public water supply is capable of violating any rights (which is denied) it is submitted that it does not in any way affect the authority of the parents in respect of their family and, consequently, the Act of 1960 is not an interference with the rights of the family guaranteed by Article 41.
 Considering the provisions of Art. 42, 1 and 2, of the Constitution, it is clear that the word "education" is not used in the wide sense so as to include "rearing and nurturing," as contended by Mr. MacBride, but is used in its narrower sense and is confined to education of a scholastic nature. It is submitted that this is obvious from the wording of Art. 42, 2, which provides that "Parents shall be free to provide thiseducation" [that is, the religious, moral, intellectual, physical and social education referred to in Art. 42, 1] "in their homes or in private schools or in schools recognised or established by the State." Consequently, it is submitted that the fluoridation of the water supply as provided for by the Act under review does not constitute a violation of the rights of the parents to provide for the physical education of their children.
 With reference to Art. 40, 3, 1 and 2, it is conceded that the Courts have jurisdiction to declare an Act of the Oireachtas void if it does not respect and, as far as practicable, defend and vindicate the personal rights of the citizen and if the Oireachtas has acted oppressively or in bad faith in passing the Act; but that has not been pleaded. It is also conceded

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	335
Supreme Court.	
 that the guarantee is not confined to the rights specified in Article 40. In reference to Mr. MacBride's contention, that among the personal rights of the citizen mentioned in this section is a right to "bodily integrity," we are prepared to concede this in the form—"a right to the integrity of the person." It is submitted that the Act of 1960 which imposes the consumption of fluoridated water on the citizens does not infringe the right to "bodily integrity" or the right to the"integrity of the person." The evidence adduced should satisfy the Court that the proposed fluoridation of the public water supply in the area where the appellant lives, while it may result in mild mottling in the teeth of some children who drink it and in a small deposit of fluoride ions in the skeletal frames of children and adults, cannot be said to involve physical danger which affects either the wholeness or the soundness of the body or to constitute an infringement of or a failure to respect the integrity of the person. [They referred to  Slaughter-House Cases (1);  Barbierv. Connolly (2);  Jones v. Portland (3);  Laurel Hill Cemeteryv. City of San Francisco (4);  Powell v. Pennsylvania (5); Jocobson v. Massachusetts (6);  Chicago, B. & Q. R. Co. v.McGuire (7);  Mark Chapman v. City of Shreveport (8); Leon de Aryan v. John D. Butler & Ors . (9);  Edward G. Tronut v. City of Milwaukee (10);  In re Art. 26 of the Constitution and the School Attendance Bill, 1942 (11);  In re Art. 26 of the Constitution and the Offences Against the State (Amendment) Bill, 1940 (12)].
Seamus Egan S.C.  in reply.
Cur. adv. vult.
 The judgment of the Court was pronounced by  Ó Dálaigh C.J.

Ó Dálaigh C.J.  :—
	3 July 

 This appeal is brought by the plaintiff, Mrs. Gladys Ryan, against an order of Mr. Justice Kenny, dated the 31st July, 1963, dismissing, with costs, the plaintiff's action, in which she sought a declaration that s. 2, sub-ss. 1, 2 and 3 and ss. 3 and 4 of the Health (Fluoridation of Water Supplies) Act, 1960, are repugnant to the Constitution and invalid.
 The Health (Fluoridation of Water Supplies) Act, 1960, was passed by the Oireachtas on the 28th day of December, 1960. In its long title the Act is expressed to be "an Act to 

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	336
Supreme Court.	
 provide for the making by Health Authorities of arrangements for the fluoridation of water supplied to the public by sanitary authorities through pipes and to provide for certain other matters connected with the matter aforesaid."
 Sect. 1 defines the terms "fluoridation," "health authority,""the Minister" and "sanitary authority." "Fluoridation"includes the addition of fluorine in any form. "Health authority" has the meaning assigned to it by the Health Act, 1947, and the Health Authorities Act, 1960. "The Minister" means the Minister for Health. "Sanitary authority"has the same meaning as in the Local Government (Sanitary Services) Acts, 1878 to 1952.
 The impugned provisions of s. 2 are textually as follows:—
 "(1) Subject to and in accordance with this Act and regulations made under subsection (3) of this section, a health authority shall arrange for the fluoridation of water supplied to the public by sanitary authorities through pipes.
 (2) The Minister may, in relation to a particular health authority, fix a date before which they shall, in relation to a particular public water supply, arrange for the fluoridation of water derived therefrom.
 (3) (a) The Minister may make regulations as to the manner in which and the extent to which health authorities shall perform their functions under this Act, and such regulations shall in particular provide for the specification of the amount of fluorine (which shall not exceed one part by weight of fluorine per million parts of water) which may be added to a water supply.
 (b) Regulations made under this sub-section may relate to one or more health authorities and different regulations may be made in relation to different health authorities."
 Sub-sect. 4 of s. 2 requires the Minister, before making regulations under the section, to cause to be made (i) a survey of the incidence of dental caries in a representative sample of pupils attending full-time day schools in the functional area or functional areas of the health authority or health authorities to whom the regulations relate, and (ii) an analysis or series of analyses of the quantities of fluorine and such other constituents as the Minister may determine in the water supplied by sanitary authorities through pipes to the public in the functional area or functional areas of the health authorities to whom the regulations relate; and it is also the Minister's duty to cause to be presented to each House of the Oireachtas a report on the survey and analysis or analyses so made. Such report, in relation to the survey, must include particulars of

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	337
Supreme Court.	
 the procedure adopted in making it and the numbers, classified by age and otherwise, of the pupils to whom it relates but must not include any information in respect of any identifiable pupil. Sub-sect. 5 of the section requires that any information in relation to dental caries in individuals which is obtained in the course of a survey under sub-s. 4 must be treated in a confidential manner. Sub-sect. 6 provides that nothing in sub-s. 4 shall be construed as imposing an obligation on any person to submit himself or any person for whom he is responsible to examination or as requiring the controlling authority of any school to afford facilities for the making of a survey under that sub-section.
 Sects. 3 and 4, which are also impugned, are textually as follows:—
 "3.—(1) Where water from a particular public water supply is supplied to the functional area of one health authority only, the fluoridation of water derived therefrom shall be arranged by that health authority.
 (2) Where water from a particular public water supply is supplied to the functional areas of two or more health authorities, the fluoridation of water derived therefrom shall be arranged by such of those health authorities as the Minister may determine.
 4.—(1) (a) The Minister may, after consultation with the Minister for Local Government, make regulations under this subsection requiring sanitary authorities to perform, as agents for health authorities, such acts, in relation to the fluoridation of water, as the Minister thinks fit and specifies in the regulations.
 (b) Regulations under this subsection may relate to one or more sanitary authorities and different regulations may be made in relation to different sanitary authorities.
 (c) Every sanitary authority shall, notwithstanding anything contained in the Local Government (Sanitary Services) Acts, 1878 to 1952, or in any local Act relating to the supply of water to the public, comply with any regulations made under this subsection which are applicable to that sanitary authority.
 (d) A sanitary authority may, with the consent of the Minister for Local Government, borrow for the purpose of defraying any expenses incurred by them under regulations made under this subsection as if they were expenses under the Local Government (Sanitary Services) Acts, 1878 to 1952.
 (e) The appropriate health authority shall pay, on demand, to a sanitary authority any expenses (including

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	338
Supreme Court.	
 payment of loan charges) incurred in a local financial year by that authority under regulations made under this subsection.
 (2) Where the Minister has, under subsection 2 of section 2 of this Act, fixed in relation to a particular health authority, a date before which that health authority shall, in relation to a particular public water supply, arrange for the fluoridation of water derived therefrom, a sanitary authority who are required by regulations made under subsection 1 of this section to perform, as agent for that health authority, certain acts in relation to the fluoridation of water shall before that date perform those acts in relation to that particular public water supply."
 As sects. 5 to 10 are not impugned, it is not necessary to notice them. Sect. 9 should, however, perhaps be noted as showing that the Oireachtas are preserving a supervisory control. The section requires that every regulation made by the Minister shall be laid before each House of the Oireachtas as soon as may be after it is made, and if a resolution annulling the regulation is passed by either House within the next subsequent twenty-one days on which that House has sat after the regulation is laid before it, the regulation shall be annulled accordingly, but without prejudice to the validity of anything previously done thereunder.
 Pursuant to the Act, the Minister in 1961 caused a survey of the incidence of dental caries among children in the Dublin-Kildare-Wicklow Health Authority areas to be carried out, and he also caused to be made analyses of the piped water supplies in each of those areas; and in the same year a report of the survey and analyses was presented to the Oireachtas. The survey of the incidence of dental caries was carried out by the Medical Research Council, and the results of the survey are summarised in the report as follows:—
 "1. The survey discloses an extremely high individual incidence and a widespread prevalence of dental caries (decay) among school children attending full-time day schools in the City and County of Dublin and in the Counties of Kildare and Wicklow. It discloses also that the incidence and prevalence were uniformly high throughout the three areas.
 2. Among the children in the age group 15 to 18 years [911] only one child was recorded as entirely free of caries experience.
 3. The survey does not disclose the early or incipient stages of dental decay and consequently must be accepted as an understatement of the total amount of caries present."
 In the case of the piped water supplies in the Dublin

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	339
Supreme Court.	
 Health Authority area the analyses were carried out by the public analyst for the city and county of Dublin. For this area the results of the analyses show that the fluorine content is less than 0.1 parts per million except in the case of the Balbriggan-Skerries, Rush, Barnacullia and Kiltiernan-Ballaly supplies, and in no case is the figure of 0.2 parts per million exceeded.
 On the 15th May, 1962, the Minister, in exercise of his powers under ss. 2 and 4 of the Act, made the Fluoridation of Water Supplies (Dublin) Regulations, 1962 (S.I., No. 75 of 1962). These Regulations, at Art. 3, required the Dublin health authority to arrange, in accordance with the Regulations, for the fluoridation of the public water supplies specified in the first schedule, being the piped water supply provided by the Corporation of Dublin and the already-named four supplies in the Dublin Health Authority area. The amount of fluorine which may be added to a water supply is provided for in Art. 3 in these words:—"The amount of fluorine which may be added to a water supply in accordance with these Regulations shall be such that the water, after the addition of the fluorine, shall contain not more than one part of fluorine per million parts of water, and not less than eight-tenths of a part of fluorine per million parts of water."
 At Article 6 of the Regulations it is provided that fluorine may be added in accordance with the Regulations either in the form of sodium fluoride or of sodium silico fluoride, each complying with the scheduled specifications. These specifications include a provision that neither substance shall"contain any toxic or harmful impurities when dissolved in water." The Regulations also provide, at Art. 8, that the fluorine content of public water supplies mentioned in the first schedule to the Regulations to which fluorine has been added shall be determined daily by a colorimetric method and, in addition, shall be determined by a distillation method at intervals not exceeding two weeks during the period of six months after the date on which the fluorine shall have been first so added, and thereafter at intervals not exceeding four weeks. For reasons subsequently stated the word "fluorine"in the Regulations must be interpreted as equivalent to"fluoride ion."
 It should also be said that prior to the introduction of the Bill for the making of arrangements for the fluoridation of water supplies the Minister for Health, pursuant to s. 98, sub-s. 3, of the Health Act, 1947, established a Fluorine Consultative Council to advise on the following matters, viz.,"Whether, with a view to reducing the incidence of dental caries it is desirable to provide for an increased intake of

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	340
Supreme Court.	
 fluorine, and, if the Council considers it so desirable, to advise as to the best method of securing such an increased intake and as to any safeguards and precautions necessary." The report of the Fluorine Consultative Council, dated the 20th May, 1958, refers to a dental caries survey of about 2,000 school children carried out in Ireland in 1952 under the auspices of the Medical Research Council (Dental Caries in Ireland. Report of M.R.C. 1952) and says:—"The Council is satisfied from a study of the Report on the Dental Caries Survey and from the experience of the dental profession, as expressed by its representatives on the Council, that there is a high incidence of dental caries widespread in Ireland" (paragraph 2). In the Report of the Consultative Council the term "fluoride"is used, and the Report points out that the terms "fluoride"and "fluorine" are interchangeable when discussing the natural occurrence of fluorine. The Report states that the concentration of fluorides in water is influenced by the geological strata through which the water percolates, and it calls attention to an investigation carried out by Drum in 1948 under the auspices of the Medical Research Council into the composition of Irish drinking waters with special reference to the distribution and significance of fluoride (Drum J. A.: Scientific Proceedings of the Royal Dublin Society, Vol. 25(N.S.), July, 1949). Drum's studies of some 42 waters showed that only 10 contained fluoride, and concentrations in these ranged from 0.1 to 0.3 p.p.m.F. (parts per million expressed as fluorine).
 The Report of the Consultative Council further points out that fluoride is found naturally as a trace element in the majority of foods, e.g., in vegetables, meat, cereals, fruit, fish, tea. Surveys carried out by McClure (McClure, F. J.: American Journal of Diseases of Children, Vol. 66, 362 (1939) and  Public Health Report, Vol . 64, 1061 (1949)) refer to over 130 foods which contain fluorides. It is not possible, the Report says, to exclude fluoride from human diets, and it adds:—"It is a normal constituent of bones and teeth"(paragraph 11). The Consultative Council, having examined the possible ill effects of increased fluoride intake, concludes its Report with the following unanimous recommendation:—"Having considered all the information available to it on the relationship between fluorine and dental decay the Council is satisfied that an increased intake of fluorine will reduce the incidence of dental caries and that it is desirable to provide for such an increased intake. The Council is further satisfied that the increased intake of fluorine can best be provided by the fluoridation of public water supplies to the level of 1.0 part per million F."

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	341
Supreme Court.	

 The plaintiff's originating plenary summons, naming the Attorney General as defendant, was issued on the 1st June, 1962, and the action was at hearing before Mr. Justice Kenny for 65 days in the months March to July, 1963. The plaintiff resides at Grace Park Road, Drumcondra, in the City of Dublin with her husband and their five children, born in the years 1950, 1952, 1956, 1959 and 1960, respectively. Her house is connected with the public piped water supply of the Dublin Corporation, and there is no alternative water supply for drinking and cooking. The nearest unpiped water supply is about three miles distant at Ballymun in the County of Dublin.
 The plaintiff in her evidence said that she was aware that fluorine in public water supplies was intended to protect against dental caries [in children]. With regard to protecting her children against dental caries she said she believed sound nutrition was very important, and that she and her husband attended to their children's diet, which consisted of one hundred per cent wholemeal bread, cheese, honey, walnuts, and an abundance of fruit and vegetables. In addition, they did not encourage their children to eat sweets, lollipops or ice cream, and they never had soft drinks except on Christmas Day. The plaintiff further said that she objected to the putting of fluorine into the public water supplies because she considered it an infringement of her parental rights, and that it was her function to see to the children's upbringing and to decide what they should have to eat and drink and all other aspects of their upbringing. Her objection as an individual was that it was an infringement of her own personal integrity. She added that if she considered that she needed medicine she went to the doctor and asked him and he would consider her case as an individual and give her the dosage he would feel right. In cross-examination she said that the putting of fluorine in the public water supply was medication in the case of children, and while it was not intended to do anything for adults she objected to it because she felt it might harm herself. She said her objection was very strong, and she had very definite views about the upbringing of children. Asked about the condition of her children's teeth, it appeared that her first child had 6 damaged teeth and 3 filled; the second child, 4 decayed teeth; the third child, five first teeth decayed or showing some signs of caries. She, however, explained that these children did not at first have the benefit of the diet they now have. The teeth of the two youngest children (aged 3 and 4 respectively), who had this diet from the beginning, were absolutely perfect.
 In addition to the plaintiff's testimony there was a mass of

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	342
Supreme Court.	
 scientific and medical evidence from an array of experts, summoned both by the plaintiff and by the defendant, and the scientific literature dealing with the subject of fluoridation over the last 30 years was referred to and analysed by the witnesses.
 The plaintiff's claim, put in general terms, rested on a submission that the fluoridation of public water supplies in accordance with the Act constituted a violation of her personal rights and the personal rights of her children, under Article 40, 3, of the Constitution; a violation of the authority of the family, under Article 41; and a violation of the family's right of physical education of children, under Article 42. Mr. Justice Kenny rejected all three submissions and, in addition, held that the plaintiff's action also failed on two other grounds, (i) that she had no contractual right to a public water supply, and (ii) that, in any event, a citizen who objected to fluoridated water could, by the expenditure of a few pounds, remove all, or almost all, the fluoride ions from the water coming through the piped water supply.
 The Attorney General has said in this Court that he did not rely upon the submission that the plaintiff had no contractual right to a public water supply and that, though pleaded, he had not relied upon it in the High Court. He did, however, support the correctness of the trial Judge's view. Mr. Justice Kenny in his judgment acknowledged that this approach might be too legalistic and too narrow. It was accepted by the Attorney General that water is one of the essentials of life, and that man therefore has an inherent right to it. In the opinion of this Court it is wholly unrealistic to say to a resident in a city the size of Dublin, who objects to using the public piped water supply, that he can avail of alternative supplies. The answer to the question, whether or not a citizen's constitutional rights have been infringed by the kind of water provided by the public water supply, should not be controlled by technical limitations arising from the law of contract. As to the second ground, that the plaintiff's action failed because she could by a simple and inexpensive device fitted to the family tap remove from the water the fluoride ions whose presence are objected to, it is enough to say this ground was not relied upon by the Attorney General in his defence, and this Court would require a fuller examination than has been given to the matter in the evidence of Dr. Fremlin before accepting it as affording, by itself, a satisfactory answer to the plaintiff's claim. The Court therefore considers it its duty, as did Mr. Justice Kenny, to examine the plaintiff's challenge to the validity of the Act in the light of the several articles of the Constitution which have been invoked.

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	343
Supreme Court.	

 Before turning to this branch of the case it is, however, necessary to prefix certain general observations with regard to the nature of this present action. The constitutionality of a statute is, in many instances, determinable by a consideration and interpretation of the terms of the statute itself without reference to evidence as to their meaning or effect. Any matters necessary to elucidate its scope in such cases are matters of which the Court can take judicial notice. In the case of this Act, however, the Court is considering a statute which uses scientific terminology, deals with a scientific procedure and requires scientific knowledge to comprehend the effect of its provisions. These are not matters which are presumed to be within the knowledge of the Court, and, accordingly, the unconstitutionality of the Act, if it be unconstitutional, cannot be determined except by reference to the particular evidence which is furnished in the case. Since evidence may differ from case to case and as scientific knowledge may increase and the views of scientists alter, the Court's determination cannot amount to more than a decision that on the evidence produced the plaintiff has, or has not, discharged the onus of demonstrating that the Act is unconstitutional. It is of importance that attention should be called at the outset to this aspect of the present case.
 The scientific evidence indicates that fluorine is the name of one of the chemical elements which, in combination with other elements, is widely distributed throughout the crust of the earth. In its pure form, uncombined with other elements, it is a gas consisting of molecules each of which is formed by two atoms with a neutral electrical charge. This gas does not occur naturally, except perhaps in small quantities in vent holes of volcanoes, but it can be produced in the laboratory by a somewhat complicated technique.
 The neutral atom of fluorine, is, however, subject to ionisation, that is to say, to the addition of an extra electron to its shell, giving it a negative electrical charge. In this form it is known as an ion, and can and does exist as a free entity, Fluorine ions (more usually called fluoride ions), in varying concentrations, are naturally present in many, perhaps in most, natural waters. Where they are not present they can be supplied by the addition to the water of any one of a number of chemical salts of fluorine which, when they are dissolved in a weak concentration, liberate free fluoride ions into the water. The process of adding such ions is known as fluoridation.
 The free fluoride ion, whether contained in water or in other substances such as tea leaves, fish or vegetables, is readily ingested by the human body. When it finds its way to the

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	344
Supreme Court.	
 teeth of children, as it does, it enters into a combination with the nascent enamel and has the effect of delaying and, to a certain degree, of avoiding the onset of dental caries, one of the most prevalent of human ills. The object of fluoridation of water which is deficient in fluoride ions is to add enough of those ions to ensure that children who drink the water will ingest sufficient ions to afford a measure of protection of their teeth.
 It is also necessary to note a change in terminology which might create confusion in the interpretation of the statute and the evidence. In the earlier literature (and even at the present time in books on inorganic chemistry) it is customary to use the expression "fluorine" ion, but modern bio-chemistry prefers the term "fluoride" ion, and often shortens this to"fluoride" without adding the word, "ion." The meaning is identical—the fluorine atom in its ionised form. The Report on the United Kingdom Mission on the Fluoridation of Domestic Water Supplies in North America, para. 37, states that the term "fluoridation" has been adopted expressly instead of "fluorinization" to make clear that the fluorine is added in the form of the fluoride ion. The Court has adopted in this judgment the term "fluoride" ion which is now the more usual terminology and which was adopted by Mr. Justice Kenny instead of the older terminology of "fluorine" ion. Nowhere in the evidence was it suggested that fluorine could be added to water supplies in the form of fluorine gas or in the form of the un-ionised fluorine atom.
 It will be convenient to deal separately with the three articles of the Constitution upon which the plaintiff rested her submission that the Act is repugnant to the Constitution.
 Article 40, 3, paras. 1 and 2, are as follows:—
 "3. 1 The State guarantees in its laws to respect, and, as far as practicable, by its laws to defend and vindicate the personal rights of the citizen.
 2 The State shall, in particular, by its laws protect as best it may from unjust attack and, in the case of injustice done, vindicate the life, person, good name, and property rights of every citizen."
 Of the further sections of this Article, section 4 protects personal liberty, section 5 the inviolability of the dwelling-house, section 6 freedom of expression, the right of peaceable assembly and the right to form associations or unions. These latter rights are expressly qualified in various ways. The Court agrees with Mr. Justice Kenny that the "personal rights" mentioned in section 3, 1 are not exhausted by the enumeration of "life, person, good name, and property

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	345
Supreme Court.	
 rights" in section 3, 2 as is shown by the use of the words"in particular"; nor by the more detached treatment of specific rights in the subsequent sections of the Article. To attempt to make a list of all the rights which may properly fall within the category of "personal rights" would be difficult and, fortunately, is unnecessary in this present case.
 It was Mr. MacBride's contention that among the personal rights of the individual is to be included a right to what he called "bodily integrity," and this the Attorney General intimated he was prepared to concede in the words, "a right to the integrity of the person." Neither counsel offered the Court any assistance as to what the limits of this right to bodily integrity were. Mr. Justice Kenny held that a right to bodily integrity was among the personal rights guaranteed by the Constitution, and he sought to define the right in these words:—"I understand the right to bodily integrity to mean that no mutilation of the body or any of its members may be carried out on any citizen under authority of the law except for the good of the whole body and that no process which is or may, as a matter of probability, be dangerous or harmful to the life or health of the citizens or any of them may be imposed (in the sense of being made compulsory) by an Act of the Oireachtas." Mr. MacBride, however, says that the Judge's definition is too narrow and he contends that any interference with bodily constitution is a violation of the right. However, for the reasons which hereinafter appear it is unnecessary to define "bodily integrity" or the "right to the integrity of the person" or to consider to what degree and in what circumstances the State might interfere with the right, whether for the benefit of the individual concerned, the common good, or by way of punishment. The Court is not pronouncing upon Mr. Justice Kenny's definition.
 The interference to which Mr. MacBride points in this branch of his argument is the effect which the fluoridation of water will have at a concentration of 1 p.p.m.F. His complaints fall under two heads: (i) the deposition of some of the fluoride ions ingested in the bones of the body, and (ii) the mottling which it may cause to tooth enamel. He referred to the process of fluoridating water as "mass medication"and submitted that the State cannot administer "drugs"through water.
 It is necessary to refer to the trial Judge's findings on these two matters:—
 (i) "Some of the fluoride ion ingested is deposited in the skeleton and some is excreted; about one-third to one-half of the fluoride ion ingested is deposited quickly in the skeleton and is thereby taken out of circulation in the human body.

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	346
Supreme Court.	
 . . . . When the water contains less than 5 p.p.m. of the ions, the evidence is coercive that it does not cause any osteosclerosis or osteoporosis . . . . If it is assumed that one-third to one-half of the fluoride ion ingested is deposited in the skeleton (and I think that the evidence supports this view), a person aged seventy who had been drinking water fluoridated at the concentration of 1 p.p.m. all his life would have a concentration of about 4,000 p.p.m. of the fluoride ion in his skeleton at that age. I am satisfied that this concentration of 4,000 p.p.m. does not produce any harmful results and does not involve any hazard. This is confirmed by the animal studies which were described in great detail in this case. In some of these, water with a concentration of 50 p.p.m. of the fluoride ion was given for seven months to pigs and for eleven months to dogs and no skeletal changes were found at the end of those periods. The evidence also establishes that the deposition of the fluoride ion increases with age so that the bone samples taken from old people show an increased concentration of it caused by the presence of the fluoride ion in water. I am satisfied that a concentration of 1 p.p.m. of the fluoride ion in the water, though it produces an increase in the concentration of the ion in the bone by a gradual process, does not involve any risk of damage to life or health for anybody, young or old."
 (ii) "If the water in Ireland is fluoridated to a concentration of 1 p.p.m., ten per cent of the children will develop mild, and very mild mottling of their teeth. Dr. Galligan distinguished between disfiguring mottling and mild and very mild mottling. I accept the view that the mottling of the teeth of ten per cent of the children in Ireland will not be an indication of fluorosis or of any damage or harm having been done to the children's teeth by the fluoride ion in the water which they have drunk. This mild and very mild mottling is not a condition which will be perceptible by most people; indeed, Dr. Galagan suggested that mild and very mild mottling might improve the appearance of the teeth. I am, however, satisfied that the mild and very mild mottling which will be produced in the teeth of some children is not an indication of any element of risk to health or of dental harm or damage to any of the children who get it."
 (iii) "Throughout the case the plaintiff's counsel sought to establish that the fluoridation of water at a concentration of 1 p.p.m. involved 'a dangerous dosage' of human beings with the fluoride ion. The first step in this argument was to establish what dose of the fluoride ion would be dangerous; the next step was an attempt to establish that the total amount of the fluoride ion taken in the food, in some drugs, and in the air, when added to the ingestion of water with a

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	347
Supreme Court.	
 concentration of 1 p.p.m., would amount to a dangerous dose. Strong reliance was placed on the quantity of the ion which is in tea and also on the fact that when a kettle of water is allowed to boil, some of the water will evaporate while the ion will not and it was argued that this would cause an increase in the concentration of the fluoride ion. It was also submitted that the Oireachtas is not entitled to take a risk with the health of the citizens and that a concentration of 1 p.p.m. in the water would, when taken with the other sources of the fluoride ion, involve a risk. I am convinced that the amount of the fluoride ion ingested at a concentration of 1 p.p.m. in the water together with the amount of the ion in the food, in drink, in the air and in drugs (in so far as we know it) does not involve any element of danger or risk to health."
 To these findings should be added Mr. Justice Kenny's earlier findings:—
 "Having heard the evidence and read the literature which it was agreed I should read, I am satisfied that the fluoridation of the public water supplies at the concentration of 1 p.p.m. will not, in our temperate climate, be dangerous to anybody, old, young, healthy or sick. I am also satisfied that there is no reasonable possibility that it may involve an element of danger or risk to life or health to any of the citizens of this country."
 "It would, I think, be sufficient for the purposes of this case to say that the plaintiff has not proved that the fluoridation of the public water supply is dangerous but I do not think that I should so confine myself. The evidence given on behalf of the plaintiff at the earlier stages in this case received wide publicity while the far more compelling evidence for the defendant received little public notice. It is possible that the evidence for the plaintiff, some of which was of a sensational character, may have created public uneasiness. Let me say then that I am satisfied beyond the slightest doubt that the fluoridation of the public water supplies in this country at a concentration of 1 p.p.m. will not cause any damage or injury to the health of anybody, young, old, healthy or sick who is living in this country and that there is no risk or prospect whatever that it will. The evidence on which I base this view consists of a number of separate items each of which is conclusive; when taken together, they are overwhelming."
 Having read the oral evidence and the documents submitted, this Court is satisfied that these findings are correct and cannot be challenged.
 The basis for the plaintiff's complaint that bodily integrity has been violated rests on the probability of mild or very mild mottling in the teeth of up to 10 per cent of the children

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	348
Supreme Court.	
 who drink the fluoridated water and on the small deposition of fluoride ions in the skeletal frames of both children and adults. Neither of these effects is harmful or involves any risk to health. The effect on the teeth is demonstrably beneficial. The purpose and effect of fluoridation is to improve children's teeth and so, indirectly, their health. These benefits to a great extent are carried forward into adult life. Adults by ingesting fluoridated water obtain little or no advantage, but neither do they suffer any disadvantages.
 Are these minute changes, almost imperceptible, usually beneficial, and at worst harmless, a violation of "bodily integrity"?
 The Court's answer is emphatically, "no." Fluoride ions occur naturally in water and in many foods. They have a beneficial effect in assisting in the formation of sound teeth in children. The Act has for its object where water is deficient in fluoride ions to bring it to the optimum level by fluoridation. Fluoride ions thus added, the evidence establishes, differ in no respect from fluoride ions naturally occurring in water. In modern life the provision of public water supplies in cities is necessarily a community obligation, and if water occurring naturally is deficient in some of its wholesome elements it is the right, if not the obligation, of the community to make good the deficiency where this can be done without harm or danger to the public. The desirability of adding to food or water elements in which they are deficient or removing elements which may be harmful has been widely recognised and frequently exercised. Water is chlorinated, salt iodised, vitamins added to margarine, flour fortified whenever these measures are shown to be beneficial.
 It is beyond question that dental caries in children has become a national problem in this State. The fact that as a disease it is not infectious or contagious or, apparently, otherwise communicable to other persons is immaterial. It can result not merely in damage to the teeth themselves but, through the existence of decayed or decaying teeth, may be injurious to general health. The State is organised for the common welfare of all its citizens and is a society arising from man's nature. Apart from particular expressed limitations contained in the Constitution, the Oireachtas may not enact legislation depriving citizens of their essential rights as human persons or as members of the family. The State has the duty of protecting the citizens from dangers to health in a manner not incompatible or inconsistent with the rights of those citizens as human persons.
 Dental caries is no new thing. It has adversely affected generation after generation and will continue to do so if

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	349
Supreme Court.	
 measures are not taken. This constitutes the type of danger from which the State has not merely the right but the duty to protect its citizens. To deal with the problem the Oireachtas has chosen a method, namely, the fluoridation of the public water supply. The plaintiff has failed to refute the evidence that this is not only the most effective method but is indeed the only effective method. The method undoubtedly does result in a minimal interference with the constitution of the body, but such interference is not one which in any way impairs the functions of the body or, to any extent discernible by the ordinary person, its appearance.
 The Court is left in no doubt that the fluoridation of water to the extent proposed in the Dublin Health Authority area where the plaintiff resides cannot be said to involve physical changes which affect in any way either the wholeness or the soundness of the body of the person concerned. The ingestion of the fluoridated water cannot, therefore, be said to constitute an infringement of or a failure to respect (gan cur isteach ar) the bodily integrity of the plaintiff or the bodily integrity of her children.
 The Court does not accept that the fluoridation of water is, or can be described as, the mass medication or mass administration of "drugs" through water. It has already been pointed out that the fluoridation is a process by which an element which naturally occurs in water is, in the case of a particular water supply, raised to a level of concentration at which it is found in wholesome water and that the fluoride ions thus added are not different in nature or action from the fluoride ions occurring naturally in water. This matter was examined in detail by the Commission set up by the Government of New Zealand to enquire into "the Desirability or otherwise of the Fluoridation of Public Water Supplies" and the conclusion was reached that "fluoride is not a drug but a nutrient and fluoridation is a process of food fortification."It is, in the opinion of the Court, a misuse of words to refer to this process as mass medication or mass administration of drugs.
 Next, the plaintiff submits that the provisions of the Act are a usurpation of parental authority as guaranteed under Article 41, 1:—
 "1, 1 The State recognises the Family as the natural primary and fundamental unit group of Society, and as a moral institution possessing inalienable and imprescriptible rights, antecedent and superior to all positive law.
 2 The State, therefore, guarantees to protect the Family in its constitution and authority, as the necessary basis of

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	350
Supreme Court.	
 social order and as indispensable to the welfare of the Nation and the State."
 The plaintiff's submission was put under two heads: (a) that the State has no right at all to interfere in the exercise of the parental authority, and (b) in the alternative, that the Act amounts to an undue interference with parental authority. The aspect of that authority which is in question is the authority of the family or the parents to provide for the health of its members in the way it thinks best. It is sought to establish, as a corollary, that parents are entitled to omit to provide for the health of their children if they so think fit. One of the duties of parents is certainly to ward off dangers to the health of their children, and in the Court's view there is nothing in the Constitution which recognises the right of a parent to refuse to allow the provision of measures designed to secure the health of his child when the method of avoiding injury is one which is not fraught with danger to the child and is within the procurement of the parent. The nature of the health problem here involved and the effectiveness of the means available for dealing with it have already been referred to. There is nothing in the Act which can be said to be a violation of the guarantee on the part of the State to protect the family in its constitution and authority.
 Thirdly, the plaintiff invoked the provisions of Article 42 of the Constitution, claiming that the legislation under review constitutes a violation of the inalienable right of the parents to provide for the physical education of their children. The relevant provisions of Article 42 are as follows:—
 "42. 1. The State acknowledges that the primary and natural educator of the child is the Family and guarantees to respect the inalienable right and duty of parents to provide, according to their means, for the religious and moral, intellectual, physical and social education of their children.
 2. Parents shall be free to provide this education in their homes or in private schools or in schools recognised or established by the State."
 Mr. MacBride contends that the provision of suitable food and drink for children is physical education. In the Court's view this is nurture, not education. Education essentially is the teaching and training of a child to make the best possible use of his inherent and potential capacities, physical, mental and moral. To teach a child to minimise the dangers of dental caries by adequate brushing of his teeth is physical education for it induces him to use his own resources. To give him water of a nature calculated to minimise the danger of dental caries is in no way to educate him, physically or otherwise, for it does not develop his resources.
 This ground of appeal also fails.

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	351
Supreme Court.	

 It remains to consider what Mr. MacBride described as his two "technical points" on the Act. Mr. MacBride's first point was based upon the terms of the definition of "fluoridation"in s. 1 of the Act, viz., "fluoridation includes the addition of fluorine in any form." Mr. MacBride says, correctly, that the element fluorine can be found in organic compounds (that is to say, compounds in which carbon is present), both in compounds naturally occurring in the dichapetalum family of plants found in certain parts of Africa and in compounds which can be produced in laboratory synthesis. He says also, and again correctly, that such organic compounds are highly toxic. From this he argues that the Act authorises the addition of highly poisonous organic compounds to water. Such evidence as is contained in the documents incorporated in the case indicates that such organic compounds are not and cannot be sources of the fluoride ion, and that their poisonous properties are due not to the action of the fluoride ion but to the action of the compound molecules of which they are formed. It is not anywhere suggested that their addition to water liberates fluoride ions, or could have the slightest effect on dental caries, or that anyone has ever contemplated using them as an addition to water. On the other hand, there is accepted and undisputed evidence that a large number of inorganic salts of fluorine (calcium fluoride, sodium fluoride, sodium silico fluoride, apatites, fluorapatite, etc.) when dissolved in water do release the fluoride ions and that the process of fluoridation consists in adding such compounds in appropriate quantities. The Act deals with a technical and scientific subject, and must be construed in the light of the scientific and technical knowledge which has been put before the Court. Its admitted object is to decrease the incidence of dental caries by the addition to water of fluorine in the form of the fluoride ion, the correct meaning of fluoridation. Despite the wide and somewhat loose wording of the definition it cannot be doubted that the word "fluoridation" is to be given its technical and scientific meaning, except in so far as this is clearly and expressly modified or extended by the wording of the definition, and that the extension by the words "fluorine in any form" must be read as "the fluoride ion as contained in or produced by any form of chemical substance." The reference is clearly intended to apply only to those numerous forms of inorganic compounds which when added to water make available the free fluoride ion or fluorine ion (if that terminology be adopted).
 Mr. MacBride's second point was taken on the terms of s. 2, sub-s. 3 (a), of the Act. The regulations made by the

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	352
Supreme Court.	
 Minister, the section says, "shall in particular provide for the specification of the amount of fluorine (which shall not exceed one part by weight of fluorine per million parts of water) which may be added to a water supply." This means, Mr. MacBride submitted, that the Minister may authorise the addition to any existing water supply of 1 p.p.m.F. no matter what its natural fluoride content may already be.
 The Court entertains no doubt that the section plainly bears the meaning which Mr. MacBride puts upon it and can bear no other meaning. Mr. MacBride referred to the provision as "an error in drafting." The Consultative Council set up by the Minister to advise on the expediency of the fluoridation of water recommended "the fluoridation of public water supplies to the level of 1.0 parts per million,"that is to say, fluoridation which would bring the fluoride content up to 1.0 part per million; and, indeed, the great weight of medical and scientific opinion fixes the optimum fluoride content of water for countries, like Ireland, in the temperate zone at 1 p.p.m. The Minister has already caused to be made analyses of the water supplies of ten counties. These analyses show that in nearly all the supplies the fluoride ion is either entirely absent or is present in such minute quantities as do not call for consideration. At Gyles Quay in Co. Louth, however, there is a concentration of .55 parts per million; and at Patrickswell, a village in Co. Limerick, a concentration of 1.0 per million. Mr. MacBride says that, for all we know, greater concentrations may be found in waters still unanalysed. This point on the construction of the statute was one which Mr. MacBride made in his opening address in the High Court and again in his closing submissions. But in the case presented on the plaintiff's behalf over a period of several weeks by a large number of expert witnesses evidence was not expressly directed to the effects of consuming water of a concentration of 2 p.p.m.F. or to the more theoretical problems arising from the addition of 1 p.p.m.F. to waters (if such should be discovered in Ireland) of greater natural fluoride concentration than 1 p.p.m. There are incidental references to the matter, as for example (i) that at this concentration a very small proportion of children ingesting the water might develop a faint brown marking which would be discernible by an ordinary person and might be sufficient to impair the appearance of a young girl; (ii) Dr. Ericsson's statement that he found no objectionable mottling at 2 p.p.m.F.; and (iii) Dr. Arnold's opinion that even from the aesthetic point of view he would be willing to bring up his children on water fluoridated to the extent of 2.5 p.p.m. There is no evidence that a concentration of 2 p.p.m.F. in water is injurious to health.

[1965]
1 I.R.	Ryan v. The Attorney General.
 Ó Dálaigh C.J.	353
Supreme Court.	

 This Court, however, cannot now consider a case which the plaintiff did not make in evidence, and did not make for the reason (one supposes) that her concern was with the proposed fluoridation of the Dublin Corporation water supply to an extent which, at its maximum, would bring its fluoride content to 1 p.p.m. The trial Judge in a very full survey of the evidence made no finding upon the point. He was not asked to make a finding. Indeed, it may be said that the matter was passed over in such a way at the trial that he could not have been asked to make a finding and, in truth, he was not furnished by the plaintiff's witnesses with the material for making a finding. This Court must therefore decline to offer any opinion upon this last matter. The plaintiff has failed to lay the ground in evidence for an examination of the problem. If the question ever assumes practical importance it will be open to investigation in future proceedings.
 The Court has no concern with the legislative policy of the Oireachtas. Its function is only to examine the statute in which that policy is embodied and to see if its provisions contravene the provisions of the Constitution. There is a presumption that a statute is constitutional and the onus of showing that it is unconstitutional rests on the plaintiff who attacks it. Where on the face of the statute nothing unconstitutional appears and the attack is based on its alleged effect, and the conclusion as to the effect has to be based on evidence of a disputed character, a plaintiff must fully satisfy the Court that its effect is such as he contends. In the view of the Court the evidence given in this case shows that a concentration of one part per million is not deleterious, and is insufficient to show that a concentration of two parts per million is deleterious.
 For the reasons stated this appeal fails.
 Solicitors for the plaintiff: Ryan & Wallace.
 Solicitor for the Attorney General: The Chief State Solicitor.
 A. B. C.
[1965] I.R. 294