Nightly News | October 04, 2012
>>> attention. a chemical in plastics called bpa and concerns about how it could cause health problems. now, a new study finds a possible cause for concern for moms and their newborns, especially boys. our report from our chief science correspondent, robert bazell .
>> reporter: jenna, like many moms, worries about protecting her kids from chemical contamination. especially the effects of bpa , found in plastics.
>> i'm avoiding plastic in general. we try to drink out of glass. all of our water bottles are reuseable.
>> reporter: a new stud zi suggests moms may be passing along bpa to their kids at birth. in a study, those with the highest levels of bpa had lower thyroid levels themselves and so did their sons. why boys? scientists aren't sure, but they've seen the same thing in animal studies . thyroid hormones help control many systems in the body.
>> if bpa is impacting the levels during pregnancy, it could be affecting the learning of children later in life.
>> reporter: it is part of many widely used plastic products. most americans have trace amounts in their bodies. while there have been many studies of bpa in animals, this is the first to show an effect on hormones in pregnant women and their newborns. in a statement, the american chemistry council said the author's speculation that bpa is linked to health affects caused by thyroid levels in women and newborns is not spored by the data. the authors know the levels reported were within normal range.
>> baby boys, but not baby girls.
>> reporter: the scientists agree the results are preliminary and agree that the kinds of changes have any effect on the children as they grow older. robert bazell , nbc news, berkeley.