Image courtesy of Women's Health

Your past could affect your baby's future. According to new research from Brown University, more than half of American women of childbearing age exceed the median blood level for at least two of three common pollutants--lead, mercury, and polychlorinated biphenyls (PCBs). These pollutants can harm the brain development of fetuses and babies.

Researchers analyzed data from a Center for Disease Control survey conducted between 1999 and 2004, which involved a nationally representative group of over 3,000 women between the ages of 16 and 49. Nearly 23 percent of study participants, or one in five American women of childbearing age, met or exceeded the median blood levels for all three common pollutants. And nearly 83 percent of the surveyed women exhibited blood levels at or above the median for one or more of the pollutants, which can be passed to fetuses through the placenta and to babies through breast milk. (Do you want to have children someday? Learn How to Protect Your Fertility.)

"Lead, mercury, and PCBs are toxic to the brain and nervous system," says lead study author Marcella Thompson, Ph.D. "Each chemical has been shown to produce birth defects, developmental delays, and lowered IQ." If a fetus or young infant is exposed to these pollutants, the risk of toxicity of these chemicals is dangerously high.

It gets even scarier: "By the time a woman's pregnant, it's almost too late to do anything about it," Thompson warns. However, it's possible that through increased awareness of these pollutants' origins, women can take action to protect themselves from exposure to these harmful chemicals.

To limit your pollutant exposure and protect the health of any future babies you may have, take note of the following factors:

Your plates

Colorful pottery may look nice on the dining room table, but beware: It may contain lead. In 2010, the Food and Drug Administration (FDA) confirmed reports from local and state agencies that traditional ceramic pottery made by several manufacturers in Mexico--and labeled "lead free"--in fact contains lead. Your safest bet is not to eat off any ceramic dishware. If you can't part from your favorite place settings, test your dishes with a lead test kit, which you can buy at hardware stores. Until you're in the clear, microwave in glass rather than ceramics, because heat can increase lead leaching, according to the FDA.

Your fish consumption

If you eat fish more than twice a week, you quadruple your odds of having higher levels of mercury and PCBs in your body, according to Thompson. If you're unsure which fish are the safest to eat, check out the Environmental Protection Agency's fish consumption advisory, which allows you to narrow down your selection based on location, fish species, and pollutant. (Look into salmon, which is packed with heart- and brain-boosting omega-3 polyunsaturated fat. Omega-3s made our list of the 4 Fats with MAJOR Health Benefits.)

Your alcohol consumption

Drinking while your pregnant is dangerous for fetal development, of course, but it turns out your alcohol consumption before pregnancy can also impact the vulnerable stages of the fetus. "We know from toxicology studies that alcohol potentiates the toxicity of mercury and PCBs," Thompson says. And while the exact reason for this occurrence is not yet known, its reality is certain, according to Thompson. Drinking too much, even if you're not planning to someday have a baby, raises the risk for cancer, heart disease, liver damage, and more. (Women should limit themselves to seven alcoholic drinks per week. Learn more about How Alcohol Affects Your Health.)

Your produce

It's great that you hit up your local farmers' market, but if you're not washing your locally grown purchases, you're at risk of ingesting potentially contaminated surface soil. PCBs have been found in surface soil at various locations, and if you swallow even a small amount of it, it's a serious health hazard, according to the Wisconsin Department of Health Services. (We all want the healthiest produce possible. Learn The Best Ways to Wash Your Fruits and Veggies.)

Your drinking water

All tap water is not created equal. While the EPA has guidelines for maximum contaminant levels of PCBs, it's still not 100 percent safe to drink. In order to get to bottom of what's coming out of your faucet, the EPA suggests contacting your water utility. Each water provider is required to prepare and deliver an annual consumer confidence report--sometimes called a water quality report--for their customers by July 1 of each year. If your water provider is not a community water system, or if you have a private water supply, request a copy from a nearby community water system.

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