1. Introduction: Rocket Science or Preponderance of Evidence?
Community water fluoridation (CWF) is a long-established [1
] but still ethically contentious [2
] public health scheme. For a scientific background on CWF, a large portion of empirical findings support its benefit of preventing dental caries, including systematic reviews [3
]. However, there are also contrarian studies raising concerns about the safety [6
] and efficacy of an “optimal” intake of fluoride [8
]. Considering the importance of evidence-based healthcare, consistent/continuous accumulation of robust scientific evidence by refuting each other [9
] for the justification of CWF seems required. If the frame of reference is set on philosophical and ethical considerations, however, the rationale for CWF is no longer empirically testable. For that matter, there remains a pragmatic issue of “acceptability” [11
] to the various stakeholders of CWF.
Ethical claims have been primarily raised by bioethicists to point out the philosophical weaknesses of CWF [12
]. Their two major arguments regarding its ethics can be summarised as the principle of non-maleficence and the breach of individual autonomy [13
]. In CWF which aims to reduce dental caries among low-income populations, no specific issues have been raised about beneficence and justice. The agendas have been refuted by proponents of CWF with scientific evidence and ethical justification briefly as follows:
: reliable evidence suggesting that CWF causes possible harms and/or adverse events on health is rare, except dental fluorosis [3
]. Even dental fluorosis can be minimised by a safe concentration of fluoride for less aesthetic and oral health concerns [5
: CWF, as a public health intervention to protect the common good, the general public’s oral health and the reduction of health inequity can override individual freedom of choice and become exempt from seeking consent by a legitimate process of the representative system [5
However, the refutations suggested are not sufficiently convincing for these contentions. For non-maleficence, whether the minimal grade of dental fluorosis is harmful or not remains debatable, leaving a further concern that the acceptance of possible harm should be approved by the individual’s choice, not the authority’s enforcement. Autonomy also leaves a remaining question about how to secure a proper agreement on the health policy for the unspecified general public, despite the possible exemption of seeking individual consent. Therefore, the agendas need to be dealt with in a different framework beyond the conventional refutation.
This article does not seek to reject or side with a certain claim on the matter of CWF. Instead of weighing up scientific findings or highlighting ethical justifications on CWF, we are trying to view the intervention from the perspective of public health ethics. The first aim of the paper is to localise where both pro- and anti-fluoridationists can agree in the discussion about CWF. The second is to suggest considerations for the ethical decision-making of CWF for better acceptability to the general public. Rather than devising a novel and effective ethical refutation of each other’s claim about CWF, caveats to lead a further discussion for the justification of CWF will be suggested. For the sake of argument on ethical issues in this paper, scientific evidence for both claims is set aside, since it is hard to find a middle ground between different interpretations of the utility of CWF. In other words, the utility of CWF is out of focus in the discussion of this paper, leaving it to be determined through more empirical studies. This is not because scientific evidence has little to do with ethical justification, but because we seek instead to concentrate on values and normativity regarding CWF.
2. Can CWF Be an Issue of Public Health Ethics?
Dental caries, as the main subject of CWF for public oral health, is a public health problem [15
]. Before starting a discussion about public health interventions, it should be warranted first whether the health issue is classified as such. According to the criteria for a public health problem suggested by Sheiham et al. [16
], dental caries satisfies all four conditions: high prevalence of the disease, significant impact on an individual level, considerable impact on wider society, and availability of prevention and effective treatment. From a more general definition suggested by Acheson and endorsed by the World Health Organization [17
], dental caries should also be dealt with “through organized efforts of society” considering its explicit social gradients [18
]. Henceforth, the coping strategy against dental caries in public
oral health should be different from that in clinical
dentistry. The banality of this common knowledge sometimes causes confusion in ethical considerations on health issues.
If dental caries is considered a public health problem, at least for the discussion of CWF, it is reasonable to apply public health
ethics to the topic, not clinical ethics. Hitherto, it has not been uncommon to view public health problems with the values of clinical ethics [19
]. That is because bioethics emerged from protecting patients in medical practice and participants in clinical research. The recognition of applying ethical values to public health and its importance for policymaking has arisen only as of late compared to clinical ethics.
Most distinctively, the “public” in public health has two prescriptive meanings: “the health of the public” and “collective interventions” [20
]. In other words, despite being under the same superordinate concept of bioethics, public health ethics should differ from clinical ethics, which focuses on individual patients’ needs and concerns from healthcare practitioners and systems [19
]. The details of the matter lie beyond the scope of this paper, but the contrast of core principles in each discipline can representatively exhibit the difference: autonomy, beneficence, non-maleficence, and justice as four principles for clinical/medical ethics [21
]; and utility, liberty, and equality as three for public health ethics [22
]. Liberty corresponds to autonomy as in public health policy for the general public and population group, and likewise equality to justice. However, what is the meaning and weight that “consent” in public health policy carries in contrast to clinical practice for individuals? For example, if a resident agrees on the health education project for the local community, to what extent and until when does the consent remain valid? Can the consent be expanded or assumed to a modified yet consistent policy with the same rationale? The core value of securing an individual’s informed consent in clinical ethics may need to be revisited for public health ethics.
For that matter, ethical frameworks have been suggested to resolve conflicts between values in public health interventions [23
]. To produce benefits, prevent harms, and maximise utility, five justificatory conditions are demonstrated as follows: effectiveness, proportionality, necessity, least infringement, and public justification. An ethical evaluation of CWF by means of the framework was also attempted (Table 1
). The table is a modified version of the framework suggested by Childress et al. [23
] to clarify the ambiguous interpretation (necessity and least infringement are hard to distinguish) [24
] for CWF. Among the proposed five conditions, the first three (effectiveness, proportionality, and necessity) have been sufficiently applied from the early stages of CWF (Table 1
). However, scientific findings still remain contentious regarding the level of evidence from the standpoints of pro- and anti-CWF [25
]. Instead of dealing with all conditions, the two latter conditions of least infringement and public justification are discussed for ethical considerations, as we expect the issue of infringement to be the point from which both parties share and start a debate. In the latter part of this paper, this point will lead to public justification, which is to be focused on in the section of “three caveats”.
3. Slanted Rungs in the Intervention Ladder
In order to better understand the infringement of individual liberty by public health interventions, let us refer to a schematic diagram. Despite its criticism for over-simplification in public health policymaking [28
], the “Intervention Ladder” [29
] is a useful metaphor representing the level of liberty infringement in public health interventions (Figure 1
). The ladder has been utilised on several occasions for the demonstration of public health ethics and modification has been attempted to improve its unidimensional approach [28
]. The model is easy to follow on the matter of liberty with the simple notion that the higher the rung is in the ladder, the more justified the intervention should be [30
Proponents of CWF try to place it on the level tagged “restrict choice.” Once CWF is implemented, virtually no other options of drinking non-fluoridated community water are feasible. It is possible to choose bottled water for drinking instead of fluoridated community water, but the unavoidable cost for alternatives can be a restrictive factor for freedom of choice. Additionally, CWF should affect the consumption of other fluoride-containing products, e.g., fluoridated salt, which endorses its restrictive nature against an individual’s free choice. However, pro-fluoridationists support CWF as a less harmful public health intervention with a certain way of obtaining consent among others, despite its restriction of choice. Particularly, in public health approaches, the strength of the whole-population strategy can be demonstrated for the prevention of dental caries in the general public rather than the high-risk strategy [32
]. Furthermore, CWF as a default choice is in accordance with the central concept of public health promotion “making the healthier choices the easier choices” [33
]. For this reason, proponents argue that the restriction of choice can be outweighed by the public health benefits CWF brings to the general public.
On the other hand, CWF is deemed to be on the highest rung to the opponents. Anti-fluoridationists can feel that their constitutional right to freedom of choice is practically deprived by the enforcement of “artificial” water treatment. Furthermore, the “mass medication” of the general public [13
] has not been legally consented to by those directly affected in health. Although the benefit of preventing dental caries by CWF can be admitted as a public health goal, unsolicited or unconsented interventions are considered intrusive paternalism [34
] or nanny-state power [30
]. Regarding the value of individual liberty, opponents put CWF on the top of the ladder, where the strongest justification is required for the enforcement of the intervention.
As previously mentioned, the same empirical findings from a scientific article [3
] have been exemplified by both opposing arguments of pro- [14
] and anti-fluoridationists [13
]. To emphasise the effectiveness and necessity of CWF would not cross the chasm between two opponents, which is poles apart. Rather, the restrictive nature that CWF bears is what both parties can agree upon, as suggested with the issue of infringement in the previous section. Its nature does not constitute a rationale to dismiss CWF in its own right, as the public benefits CWF can bring should not be underestimated and restriction of choice is a demand for alternatives of least infringement, not a “deal-breaker” of public policy [24
At present, what matters more about the ethical considerations of CWF highlights how to resolve the inherent restriction of choice. The resolution of the matter seems to reach a consensus that both proponents and opponents can co-occupy. We present three caveats to justify the infringement of public health policy: procedural justice, social context, and maintenance of trust. These caveats are derived from the effort to resolve the restriction of choice and minimise the infringement through public justification.
5. Conclusions: You Can Lead a Horse to Water, but You Cannot Make It Drink
To date, we have found that CWF needs to be justified in ethical considerations, and public health ethics is an adequate framework for the discussion. For the different recognition of CWF, the metaphor of the intervention ladder was applied, confirming least infringement to be the matter of different rationales for the same intervention. Before establishing the ethical justification of the public health intervention, three caveats were suggested: procedural justice, social contexts, and maintenance of trust. Procedural justice, implemented with accountability for reasonableness, can help justify and resolve the issue of infringement by CWF through the fair procedure of four conditions. Considering social contexts and the maintenance of trust can allow CWF to be suitable for the community and transparently communicative for the dental profession, which will be a big challenge and change for the profession in the future. Now that the underlying cognitive dissonance is identified and the caveats for ethical considerations have been offered, further studies are advised about how to reach a consensus on the practical implementation of CWF among relevant stakeholders for the sake of public oral health.