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POPs AND THE NEW INSIGHT INTO
ENVIRONMENT-RELATED DISEASES
M.V. Cherkasova, Co-ordinator of International Network "Children Health, Environment and Security" In the last decade of the last century and the last millennium, the scientific community witnessed a major event, that, unfortunately enough, so far remains largely underestimated. The event in question is the new scientific understanding of dependencies between human health (and health of all other living things of the planet) and chemical contamination of the environment, caused by human activities. In this case, monograph "Our Stolen Future" (by T.Colbourne, D.Dumansky and D.P.Mayers), published in 1996 in the United States, played a decisive role. Having analysed a huge array of available research data, the authors demonstrated, that synthetic, alien to biosphere organic substances and some metals affect living matter in an absolutely different way, than already known toxins. Contrary to toxins, which affect separate organs and induce specific poisoning effects, the new substances affect internal regulation systems - hormone/endocrine systems and, due to these effects, are called "hormone disrupting chemicals". I would like to remind, that hormones - i.e. chemical substances, produced by endocrine glands - are transported by blood-circulation systems and regulate all processes in human body. Endocrine disrupters act as quasi-hormones and cause severe disruptions of embryonic development, these substances disrupt nervous, reproductive and immune systems, affect intellectual capacity and behaviour patterns of humans and animals. The problem is of enormous scale. In 50 recent years, hundreds of thousands of new chemicals have been developed, produced and marketed (mainly petrochemical products, that never occurred in natural environments earlier). Within the above group, persistent organic pollutants (POPs), including hormone disrupting chemicals, pose especially high risks. Thousands of new compounds enter the environment every year, and only few of them have been tested for toxicity. At the same time, these substances are more and more widely used in all spheres of life of modern societies - as pesticides in agriculture, in food processing, in production of packaging, in medicine, for production of toys, etc. Screening the new substances for hormone disrupters is an extremely complicated and costly venture. Nevertheless, some initial "black lists" have been already developed. For example, researchers of Tokyo National Institute of Health Studies have developed the list of 140 substances. The World-wide Fund for Nature has developed the list of 55 chemical compounds, classified as endocrine/reproductive disrupters. The range of these substances incorporates chlorinated pesticides (first of all DDT, dioxins and furans, polychlorinated biphenyls, etc.). About 30 different health impacts of these substances on humans and animals have been proven, the range is expected to grow as new data will be accumulated. The already proven impacts incorporate the following ones: reduction of sperm counts and infertility; malignant tumours of testicles and prostate gland; cryptorchism (developmental defect marked by the failure of the testes to descend into the scrotum); abnormal development of testicles; sexual precocity (including premature breast development of girls); reduced biosynthesis of sex hormones; alteration of offspring sex balance (lower shares of male descendants); malignant tumours of ovaries, breast cancer; intersexuality; diverse reproductive and development disorders; higher incidence of spontaneous abortions, birth defects and stillbirth; immune disorders, causing development of asthma and diabetics; thyroid gland pathology; body inanition syndrome, reduction of the cognitive function, different behavioural deviations, etc. At the international meeting of concerned experts, dedicated to the problem (Japan, late 1999), D.P. Mayers (one of the authors of "Our Stole Future") said the following: "A hundred or more of new chemicals circulate in our blood vessels. Before this century, these chemicals were not found in humans. We, our children and grandchildren serve as living test tubes in an experiment with absolutely unpredictable outcome. There is not a single mother at the Earth, whose body does not contain these chemicals, and a mother supplies her foetus with these chemicals". The meeting participants agreed, that the most serious threat of these chemicals is associated with their hormone disrupting properties, that unborn children are under the most serious threat. According to researchers, endocrine disrupters, even at very low levels, affect all aspects of human development, starting from embryonic stage. These important concept shaped the new understanding of nature of environment-dependent diseases. Nicholas E. Ashford and Claudia S. Miller presented their report "Low-dose Chemical Impacts as a Problem of Science and Management Policies" at Amsterdam Conference "Children Health and Environment" (August 1998). It was the Conference, where the International Network "Children Health, Environment and Security' (INCHES) was founded. According to the above authors, for the time being, we are only beginning to realise the whole complexity of interdependencies between chemicals and diverse and numerous public health problems, approaching dramatic revision of principles of traditional toxicology and medical science. According to the report authors, the range of "diseases of 21st century", associated with low-dose chemical impacts, incorporates: birth defects, diverse immune disorders, cognitive deficiency, hyperactivity syndrome, depression, asthma, endocrine disorders (mainly reproductive ones), encephalopatia, some forms of cancer, etc. These diseases have some particular features:
It is obvious, that humankind faces now a huge and almost unidentified challenge and, as a result, it is absolutely necessary to develop a new social strategy for addressing this extremely dangerous phenomenon. Hormone disrupting chemicals require the society to implement immediate counter-measures. To this end, the precautionary principle should be used as a key one. The precautionary principle was declared at the Global Summit for Environment and Development in 1992 - "In cases of potential threats of serious or irreversible damage, lack of definite scientific knowledge cannot be used as a reason for delaying cost-efficient measures for elimination of environmental threats". Therefore, in this case, the precautionary principle attempts to prioritise interests of potential victims of environmental pollution, rather than interests of industrialists, who always require absolutely accurate scientific evidence of damages caused. It is necessary to emphasise, that in the case of hormone disrupting chemicals, which produce tangible impacts at negligible levels, such evidence is technically difficult, costly and sometimes even impossible to collect. Detailed discussion of the strategy of protection from the chemical threat is contained in report "Chemicals in European Environment: Low Doses and High Stakes" (UNEP and the European Environmental Agency - 1998) in Chapter "The New Paradigm of Chemical Management". The list of references of this detailed report incorporates about 120 sources, mainly published in the last decade. Numbers of publications on different aspects of the problem continue to grow. In 2000, monograph "Hormonal Chaos" by Sheldon Crimsky was published in the United States. I consider all the above issues as fairly relevant and significant to us, because the problem of environment-dependent diseases in Russia became of major practical significance long ago. Russian specialists come to conclusions, similar to the above described ones. For example, at the Third Congress of Russian Paediatricians, dedicated solely to health and environment problems (Moscow, 1998), Academician Yury Veltistchev expressed the idea, that environment-induced children pathologies are characterised by decisive roles of disruptions of nervous, endocrine, immune and reproductive systems, while, in the majority of cases, organ-specific disorders play secondary roles. In these cases, adverse impacts of agents of different nature on children's health follow non-linear, zero-threshold impact models. In other words, in the case of children, there are no safe dozes of toxicants (so called MACs), chemical substances might produce toxic effects in negligible concentrations. Available experience of independent health assessments of population groups, that were exposed to chemical and radioactive contamination, clearly suggest, that application of traditional models is not appropriate or is even misleading (in particular, application of maximal allowed concentrations - MACs - for estimation of health damages, especially in the case of children). It is clear, that the new approach would require really revolutionary changes in assessment of health impacts of operations of production facilities, military and space activities, transportation routes and different industrial accidents. It will be necessary to develop conceptually new methodologies for research and assessments, adequately reflecting modern understanding of the situation. Besides that, the problem will inevitably require application of new principles and methods for treatment and prevention of these diseases, development of a new generation of drugs, etc. Summing up - it will be necessary to develop a new comprehensive public health strategy for 21st century. It is clear, that implementation of all these measures will require active public participation. I must stress, that only efforts of non-governmental organisations, independent scientists and journalists allowed to attract necessary attention to problems of POPs and endocrine disrupting chemicals. We may definitely claim that without public pressure, Stockholm Convention on persistent organic pollutants would never be signed. Unfortunately enough, Russia still has not signed the Conventions, as it was explained, "due to technical reasons". It means that the Russian environmental community has a broad scope for action. It is necessary to ensure Russian signature under the Convention, but it would not be enough, it is necessary to ensure practical compliance with the Convention's provisions. The latter objective is the most difficult one, it will require permament efforts. Problems of persistent organic pollutants and endocrine disrupters are high in the agenda of Eurasia division of International Network for Children Health, Environment and Security. Task force "Monitoring and Neutralisation of POPs" has been established, headed by S.S.Yufit, Doctor of Sciences (Chemistry). In February 2001, in Suzdal, at a workshop of our network, we discussed further activities of the task force. Generally, the workshop participants recommended to disseminate available information on the issues involved. We regularly provide information on the problem in electronic newsletter of our network - "Children in the Third Millennium". In the nearest future we plan to publish abridged translation of "Hormonal Chaos" by Sheldon Crimsky with preface of S.S.Yufit, Doctor of Sciences (Chemistry), and V.M.Lupandin, Doctor of Sciences (Medicine). A special issue, dedicated to "Endocrine Disrupters in Environment and Impact Minimisation Methods" is being developed. In collaboration with Baikal Environmental Wave we prepare for publication the second edition of Mary O'Brayan's paper "Our Toxins' Use Strategy, Out Stolen Future and Our Opportunities", published in response to "Our Stolen Future". Besides that, we plan to publish the Russian version of the monograph itself (the book was already translated into dozens of languages). Besides that, we plan some practical activities as well. At the meeting in Suzdal, we supported recommendations for implementation of a joint action for prevention of incineration of domestic garbage, containing polyvynylchloride residues (incineration of PVC is accompanied by formation of dioxins). Baikal Environmental Wave (Irkutsk) has the major experience in the sphere - we already disseminated its leaflet "Why one should not burn garbage in the yard" within our network. In the course of our meeting in Suzdal, members of POPs task force made a major practical action: they collected breast milk samples of Suzdal women for dioxin determination. Several years ago, similar activities were carried out by a group led by S.S.Yufit, within the framework of a special program of the World Health Organisation. At that time, breast milk samples were collected in 6 towns of Russia (mainly in industrialised ones, while Suzdal was incorporated into the research as a baseline, control city, as an environmentally clean location). The research results were astonishing - in some respects breast milk of Suzdal women was even more contaminated, than samples from heavily polluted Dzerzhinsk. It might be attributed to consequences of massive agriculture contamination (including consequences of incineration of PVC film, used in vegetable cultivation). At that time, the above analytical results justified incorporation of Vladimir oblast - including Suzdal - into the Federal Program for Protection from Dioxins . If you want to join the Network or to receive our publications - contact us: 115407 Moscow, PO box 67; phone/fax (095)118-8686 European INCHES co-ordinators: Marie Louise Bistrup, Denmark: |