Environmental poison makes girls more girlish

Hormone-active environmental substances change gender-typical behavior among German schoolchildren

Girllier by PCBs in the womb? © SXC
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Hormone-active chemicals such as PCBs or dioxins affect the behavior of children - even in Germany: boys, who were exposed in the womb slightly increased levels of these substances show rather a lighthearted behavior, girls on the other hand, the reverse. This shows a study of German researchers. Although these substances have been banned for years, they are still found in our environment and in breast milk.

Polychlorinated biphenyls (PCBs) are organic chlorine compounds that have long been used in electrical appliances and as plasticisers in plastics. Because they are highly carcinogenic and also belong to the hormone-like substances, they were internationally banned by the Stockholm Convention in 2001, they belong to the "dirty dozen" of the worst chemical toxins. Nevertheless, these hormone-active substances can still be detected today almost everywhere in the environment. They were released into the atmosphere through chemical accidents and improper storage of chemical waste and spread through the atmosphere.

From animals is already known that these pollutants disturb the hormone balance, males become infertile or feminine. There is also evidence in humans that increased exposure to these pollutants in the womb may affect children's hormonal and mental development. Environmental scientists from Bochum, Dusseldorf and Münster have now investigated whether the present in Germany in the environment existing PCB and dioxin levels have a measurable effect on gender-specific behaviors of children.

Examined pregnant women in Duisburg

For their study, the researchers measured the concentrations of 35 PCBs and dioxins in blood and breast milk in 232 pregnant women from Duisburg. Seven years later, they asked the mothers about the children's toy preferences, their play behavior, and other gender-related behavioral traits. The survey was based on an internationally standardized questionnaire.

The analysis initially showed that the concentrations of PCBs in blood and breast milk were on average around 107 nanograms per liter compared to surveys from the 1990s were rather low, as was the case for dioxins with 11.6 picograms per liter. Nonetheless, the comparison of the respective burden of mothers with the behavior of their children showed a correlation: the higher the value of PCBs in blood and especially in breast milk, the more often the gender-specific behavior of their children was changed. display

Pollutants make boys more girlish

At higher levels of exposure to endocrine disruptors, school-age boys behaved more girlishly, whereas girls showed a lessened female behavior. This effect is very clear even with the relatively small number of participants in the study, the researchers report. It also shows a clear dose-effect relationship. "Our study shows that even a relatively low prenatal burden of dioxins and PCBs can change the sexual behavior of schoolchildren, " concludes Gerhard Winneke from the Heinrich-Heine-University D sseldorf and his colleagues,

Although measurements show that the concentration of PCBs and dioxins in the environment is gradually decreasing. The researchers emphasize, however, that there are many other hormone-active substances that are still in use and that could produce similar effects. (Environmental Health Perspectives, 2013; doi: 10.1289 / ehp.1306533)

(Leibniz Institute for Environmental Medicine - IUF, 11.12.2013 - NPO)