The Precautionary Principle Saves lives

"In 1854, in London, John Snow observed that there was a high incidence of cholera cases in an area where water was supplied by a certain company. He reported it to the city council of London. In response to his report, the city council ordered the company to improve its water system. Thanks to this quick order, the incidence rate of cholera soon began to decrease.

Robert Koch established, beyond doubt, a bacteriological cause-result relationship when he discovered Biblio cholerae and defined Kocho's principle of causality at the turn of the century. Therefore, the action taken by the city of London can be regarded as an execution of the Precautionary Principle.

However, in Japan, when Minamata disease was initially noted along the coast of the Shiranui Sea in 1953, the Precautionary Principle was not applied. Minamata disease was identified as the outcome of consuming fish caught in Minamata Bay in 1956 where a chemical plant was discharging wastewater. Non-human fish eaters, such as cats and sea birds, also succumbed, prior to human victims, an illustrative example reflecting common knowledge of environmental toxicology. However, the official declaration from the Government acknowledging methylmercury as the causative agent of the disease was not made until 1968. The crucial reason for this delay was that the toxicological causal link between Minamata Disease and methylmercury was rejected until then.

If the epidemiological causal relationship had been accepted, and appropriate action based on the Precautionary Principle had been taken, the number of victims (about 500 deaths and more than several thousand people became this desease) would have been greatly reduced."


Give Information to Consumers

"Now, how should we deal with endocrine disruptors?

The primary difficulty of making estimations of health effects related to EDs is the uncertainty associated with identifying and counting these effects. In the cholera and Minamata Disease epidemics, there were readily identifiable clinical manifestations followed by deaths.

In the case of EDs, identifying both results (effects) and causes poses an enormous problem. First, infinitesimal amounts of EDs may exert an effect without demonstrating any observable threshold. Second, there are numerous endocrine disrupting chemicals in the environment. Third, they may disrupt endocrine signal transmissions during the fetal stage when gene-expression takes place and organ development is most active. Thus, the resulting effects can only be observed in the next generation.

What sort of countermeasures can social medicine provide to address this problem characterized by potentially devastating hazards without clear identification in each case? Since a determination of causality is not feasible in individual cases, it can only be done by operating a cohort study on groups with different degrees of ED exposure. Resorting to the Precautionary Principle may not be able to be justified before an epidemiological causality is demonstrated.

Thus, the remaining countermeasure appears to be based on the fact that the primary route of ED uptake is through diet: Information regarding the ED contamination of food must be disclosed without fail, so that consumers can make choices based on that information. The role of social medicine at this stage appears to be to provide consumers, especially reproductively active women, with knowledge related to ED, and to encourage them to behave wisely.

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There were also about 240 posters presented at the symposium. The following posters are related to our daily lives.


Styrens may effect learning ability:

Poster title: "Behavioural change in pups produced by perinatal styrene exposure during their brain development stage," by Hiriyuki Aikawa, Takahiko Yoshida, Takaaki Kinoshita, Mitsugu Sakabe, and Fujio Kayama.
D61


Bisphenol A leaching from dental sealant:

Poster title: "Analysis of bisphenol A in polycarbonate using as dental materials," by Kou Yajima, Miki Shimizu, Kayoko Kato, Hiroyuki Nakazawa et al.
A27


Soybean may suppress cancer:

Poster title: "Suppressive effect of soy bean isoflavones on proliferation of breast cancer cells induced by nonylphenol," by Yukihiro Yoshida, Takanori Teramoto, Katsunori Ikeda, Yukio Iemori.
B6


Pyrethroid agricultural chemicals are endocrine disruptors: Poster title:

"Evaluation of estrogenic activities of pyrethroid agricultural chemicals," by Naruhito Yamashita and Masahiro Kawanishi
F6

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"Pregnant women should avoid exposure to endocrine disruptors as much as they can. It is recommended not to use plastic food wrap in microwave ovens, pesticides, cigarette, and alcohol. When we feed bispehnol A to pregnant mice, bishenol A bioaccumulates in the fetus's body. It would be wise for pregnant women to avoid EDs."