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New Dangers from Chemical Pollutants
May 18, 1998
Chemicals released into the environment are coming back to haunt humans. (Photo: Kyodo)
The threat of "environmental hormones," which are believed to disrupt the endocrine system in humans and animals, has emerged as a worldwide environmental concern. In Japan, as in many other countries, abnormal phenomena have been reported that are suspected to have been triggered by these hormone disruptors, and the government has set aside additional funding for research in the hope of formulating effective countermeasures.
Sky-High Dioxin Levels in Japan
Environmental hormones, which are called endocrine disruptors or hormone mimics in scientific terminology, is a generic term for chemical substances that enter the body and mimic hormones, thus disrupting the functions of hormones naturally secreted by the body. They are difficult to decompose and have a high degree of residuality.
About 70 substances are thought to be hormone disruptors, including dioxin, polychlorinated biphenyl (PCB), and bisphenol A, a plastic material widely used in daily life. Dioxin, in particular, is found in large quantities in the atmosphere surrounding Japanese cities--about 10 times more than in the urban areas of the United States and Europe--because Japan mainly relies on incineration for garbage disposal, a method that greatly reduces the volume of waste.
Many similar cases have been reported in and around Japan, such as female snails with male genitalia. Also, at a meeting of the Japan Fisheries Society held in Tokyo in April 1998, it was reported that 30% of male carp in Tokyo rivers had abnormal seminal glands and that male flatfish in the sea off Tokyo's coast had been producing egg-yolk protein, which is a characteristic of females. A suggestion was made that these creatures in the wild were affected by environmental hormones.
As for how environmental hormones have affected humans, medical researchers at Teikyo University announced in March that a survey of the sperm of 34 men in their twenties revealed that only one man cleared all the standards of the World Health Organization for sperm volume, density, liveliness, and other factors, raising speculation that environmental hormones might be involved.
Surveys conducted by research institutes on polychlorinated containers, such as nursing bottles and tableware for infants and schoolchildren, have all revealed that when hot water, oil, or alcohol is poured on them, they produce the suspected environmental hormone bisphenol A. Although concentrations were lower than the level allowed by the Food Sanitation Law, concern is spreading among parents and others.
Edited by Japan Echo Inc. based on domestic Japanese news sources. Articles presented here are offered for reference purposes and do not necessarily represent the policy or views of the Japanese Government.