Chemicals in plastics may be a threat to male fertility

To study the impact of everyday chemicals on fertility, federal researchers recently spent four years tracking 501 couples as they tried to have children. One of the findings stood out: while both men and women were exposed to known toxic chemicals, men seemed much more likely to suffer fertility problems as a result.

The gender gap was particularly wide when it came to phthalates, those ubiquitous compounds used to make plastics more flexible and cosmetic lotions slide on more smoothly. Women who wore cosmetics often had higher levels of phthalates in their bodies, as measured by urinalysis. But only in their male partners were phthalate levels correlated with infertility.

“It’s the males in the study that are driving the effect,” said Germaine Buck Louis, an epidemiologist at the National Institute of Child Health and Human Development and lead author of the report, published in February in Fertility and Sterility. “They’re…