Pollutants Linked to Lower Fertility Rates in Men and Women
November 16, 2012
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Just because a chemical has been banned for more than 30 years doesn't mean it can't still affect you.
According to a new study out this week, exposure to common chemicals such as (PCBs) may lower fertility in both men and women.
Reporting in the journal Environmental Health Perspectives, researchers say that these pollutants, outlawed since 1979, as well as industrial compounds and pesticides that are no longer manufactured but still remain in older products and the environment, can decrease couples’ ability to have children by up to 29 percent.
What is alarming about the study is the fact that these chemicals are ubiquitous. They're found in the soil, water and in the food chain. They don't readily decay, and may stay in the environment for decades. Some of these chemicals, known as persistent lipophilic organochlorine pollutants, accumulate in the fatty tissues of livestock that are eventually slaughtered and consumed by people.
Other chemicals, called perfluorochemicals, are used in clothing, furniture, adhesives, food packaging, heat-resistant, non-stick cooking surfaces and in the insulation of electrical wire.
Earlier research has shown PCBs to cause a number of health problems in animals, including cancer and problems with the immune system, reproduction, nervous system and hormonal system.
For the new study, scientists at the National Institutes of Health created the Longitudinal Investigation of Fertility and the Environment (LIFE) followed 500 couples who stopped using contraception for a period of either 12 months or until they got pregnant, whichever came first.
Researchers then measured their blood for the presence of 63 organic pollutants and pesticides that fail to degrade in the environment but are absorbed by the livestock we eat.
For women exposed to PCBs and the perfluorchemical known as perfluorooctane sulfonamide, the odds of conception dropped by 18 percent to 21 percent.
Perfluorooctane sulfonamide belongs to a class of chemicals known as perfluoroalkyls, which have been used in fire-fighting foams.
For men, the odds dropped 17 percent to 29 percent for those exposed to PCBs and DDE, which is produced by degrading of the pesticide DDT. Although DDT was banned in the United States, it is still used in some countries.
The study is unique in its focus on the effects in men. And understanding some of these factors that may lower fertility among both men and women as well may be critical to finding more effective ways of helping infertile couples to start families.
In the paper, authors acknowledge that their findings will be more convincing if other scientists repeat the experiment and get similar results.
What do you make of the study's findings? Let us know in the comments.