Just a few days after Canada officially declared BPA toxic, there's more big news on the BPA front. This time, that news is focused on moms-to-be.

A new study, conducted by researchers at the Harvard School of Public Health and published online in the journal Environmental Health Perspectives took a close look at the varying BPA levels in pregnant women and narrowed down the behaviors that put new moms and babies most at risk.

The study found that pregnant women who eat canned vegetables or work as cashiers show the highest levels of bisphenol A, while those who smoke or are exposed to secondhand smoke also had a higher concentration of the hormone-disrupting chemical.

Researchers tested the urine of 386 pregnant women from around Cincinnati, Ohio, at the 16th and 26th weeks of pregnancy and within 24 hours of giving birth.

The women who consumed canned vegetables at least once a day had 44 percent more BPA than those who didn’t eat them. Interestingly, the BPA levels of those who only ate canned fruit wasn't as high as those who ate canned vegetables.  

Pregnant cashiers also had roughly 40 percent more BPA in their urine than women in other professions. And women who smoked or were exposed to secondhand smoke had about 20 percent more BPA in their urine than those who weren't exposed to tobacco smoke. 

So what does this mean for women who are pregnant or hoping to become so? It's just a few more factors to add to that dreaded list of things to avoid while pregnant. Smoking and secondhand smoke were already on there; now add canned food to the list. If you're currently working as a cashier, it might be time to consider a change of employment.

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