Arsenic has made major headlines over the past several months, as health scares have sprung up over levels of the element in apple juice, rice, and even organic baby formula. In each instance, the levels of arsenic found were compared to the "safe" level of arsenic that the U.S. Environmental Protection Agency (EPA) has designated for drinking water. But new research shows that even this low level may be harmful to pregnant women and young children.


In 2006, the EPA set the arsenic limit for drinking water at 10 parts per billion — a level deemed nontoxic and acceptable for human consumption. This low level was ordered to protect Americans from the the adverse health effects such as nausea, vomiting, blindness and even paralysis. But new research from the Marine Biological Laboratory in Woods Hole, Mass., and Geisel School of Medicine at Dartmouth finds that even this low level of arsenic might not be safe to drink.


In an animal experiment that studied pregnant and lactating mice and their offspring, researchers attempted to determine if mice exposed to arsenic in utero were more susceptible to the flu. What they found was that after giving the mice the arsenic-laced water, the pregnant and lactating mothers experienced problems with their lipid metabolism, which caused lower levels of nutrients in their blood and breast milk. So the pregnant moms had lower levels of nutrients in their bodies, and so did their growing babies.  


These nutrient deficiencies lead to growth and developmental deficiencies in their offspring — in other words, the babies were much smaller than those born to moms who had not been drinking arsenic in their water. The effects continued to compound during breastfeeding. Researchers never continued with the flu portion of the experiment because the effects of giving pregnant moms arsenic-laced water were so profound that they didn't need to.  


If your pregnant and concerned about this study it may be worth installing a water filter (make sure it is one that will filter arsenic) in your kitchen.


Related: How polluted is U.S. drinking water?


The opinions expressed by MNN Bloggers and those providing comments are theirs alone, and do not reflect the opinions of While we have reviewed their content to make sure it complies with our Terms and Conditions, MNN is not responsible for the accuracy of any of their information.