Plasticizer may be tied to boys' breast enlargement

NEW YORK (Reuters Health) - A report out today points to yet another possible harmful effect of exposure to phthalates -- a controversial plastics chemical used widely in the manufacture of consumer products.

Researchers from Turkey found higher blood levels of the most commonly used plasticizer, DEHP, in a group of boys with abnormal enlargement of the breasts -- a common condition seen in up to 65 percent of adolescent boys called pubertal gynecomastia. The condition usually resolves on its own after boys get through puberty.

“Unfortunately,” Dr. Elif N. Ozmert from Hacettepe University in Ankara, Turkey noted in an email to Reuters Health, “we are exposed to this (chemical) in many ways via direct contact,” breathing, and eating.

“A few examples are personal care products, paints, building materials, household furnishing, clothing, dentures, children’s toys, cleaning materials, insecticides, food, certain medical devices and pharmaceuticals.”

Studies have shown that phthalates accumulate in tissues and can have harmful effects, Ozmert and colleagues note in a report posted online today in the journal Pediatrics.

Ozmert’s team determined levels of DEHP, and its byproduct MEHP, in 40 boys aged 11 to 15 with gynecomastia and 21 healthy age-matched boys with no history of gynecomastia.

They detected DEHP in all blood samples and MEHP in all boys with gynecomastia and in 19 of 20 control boys.

Blood DEHP levels were markedly higher in the boys with gynecomastia than in those without this condition. MEHP levels were also much higher in the boys with gynecomastia than their healthy counterparts.

According to the investigators, for boys with the highest MEHP levels, the risk of breast enlargement was nearly 25-fold higher.

Phthalates “could be” involved in the development of pubertal gynecomastia, Ozmert and colleagues conclude. They caution, however, that the study was small and does not allow for any definitive conclusions.

Steve Risotto, Senior Director, Phthalate Esters, at the American Chemistry Council has concerns about the study. “This study does not fit with established science,” he said in a statement to Reuters Health.

For example, the researchers found normal hormone levels, “even though this is likely to be a hormone-induced condition,” Risotto noted.

The researchers are suggesting that DEHP must be mimicking the activity of estrogen, Risotto said, which would explain the excess gynecomastia. “But, a significant amount of laboratory data tells us that neither DEHP nor MEHP shows estrogenic activity,” he said.

And Risotto said that “perhaps the most interesting finding” is that DEHP and MEHP levels in the blood were not linked to decreased testosterone, which other researchers have said could be how they affect the development of male reproductive organs.

Still, until further studies are conducted, Ozmert suggests trying to limit exposure to phthalates. “Although we can’t achieve zero exposure, we can decrease it.”

To do that, Ozmert recommended avoiding the use of plastic cups and food coverings, particularly for hot foods. Such cups - including baby bottles -- should never be used in microwave ovens, Ozmert said. The researcher also advised against plastic toys and unnecessary cosmetic use, and recommended hand-washing to prevent contamination.

SOURCE: Pediatrics, December 2009.