Phthalates Affect Way Young Boys Play
Boys With High Phthalate Exposure in Womb Show Less Masculine Play
Exposure to Phthalates continued...
Exposure to two of the nine phthalates, DEHP and DBP, was associated with less masculine play behavior, the researchers found.
For example, Swan says, ''If the mother's MEHHP concentration [one of the phthalate metabolites] was high, in the upper quartile, the odds that her boy had a score that was less masculine [in play behavior] was five times greater than mothers whose MEHHP was in the lowest quartile."
Exposure to phthalates may lower testosterone production in the fetus during a crucial period of development, at about 8 to 24 weeks' gestation, Swan says, when the testes begin to function, and in doing so alter sexual differentiation in the brain.
The study results should be a wake-up call about the potential dangers of phthalate exposures, according to Sarah Janssen, MD, PhD, MPH, staff scientist at the Natural Resources Defense Council, who reviewed the study results for WebMD.
''This study by itself shouldn't make parents panic, but I do think we are beginning to accumulate more and more evidence that exposure to phthalates, especially during pregnancy, can be harmful for the development of baby boys," she says.
Janssen cites animal studies, finding that exposure to the chemicals can cause a wide range of male reproductive harm, including undescended testicles, birth defects of the genitals, and infertility later in life.
"What this study adds is, we know testosterone and estrogen are also very important for the development of the brain and sexual differentiation of the brain,'' she says. The new study suggests that interfering with testosterone levels during critical periods of development can affect later behavior, she says.
Advice for Moms-to-Be
Limiting exposure to the chemicals is best, say Swan and Janssen, although the chemicals are ubiquitous.
Under a federal law passed in 2008, the Consumer Product Safety Improvement Act, six phthalates are now banned from use in toys such as bath toys, dolls, and teethers. Some products carry a "No phthalates" label.
One way to avoid exposure, Janssen says, is to avoid heavily fragranced shampoos and lotions as well as air fresheners.
What's needed next, according to Janssen, is more attention on limiting exposure to the chemicals to women who are pregnant or those of childbearing age.
Swan's study was funded by the National Institutes of Health, the Environmental Protection Agency, and the State of Iowa.