Oct. 6, 2009 -- New research suggests a link between prenatal exposure to the chemical bisphenol A (BPA) and increased aggression in girls, but not boys, at age 2.

The finding is far from conclusive, but the study is the first human trial to attempt to examine whether BPA exposure in the womb influences behavior in early childhood.

BPA has been used for more than three decades to make plastic bottles and other products shatter resistant and clear. It is also used in the lining of many canned foods and in a wide range of other commercial goods.

The chemical was found in the urine of more than 90% of Americans in a random sample conducted by CDC researchers in 2007.

For close to a decade, scientists have debated whether exposure to BPA through commercial products poses a health threat to humans. Hundreds of animal studies suggest it might, but only a few human studies have been published.