Indoor air in schools may expose children to PCBs

June 28 (UPI) -- A new study has found that concentrations of airborne polychlorinated biphenyls, or PCBs, inside schools could expose students to the compounds at higher levels than through diets.

Researchers at the University of Iowa who conducted the study, published June 28 in Environmental Science & Technology, tested the air inside and outside six schools, four of which are within 1.5 miles of two waterways serving major industries in the area.

PCBs are a group of synthetic chemicals used in hundreds of products for nearly 50 years before being banned. The chemicals were dumped by industries into rivers and streams resulting in some of the most expensive environmental clean-ups in U.S. history.

PCBs can remain in soil and water, and can accumulate in animals leading to exposure to humans through environment and diet.

Results of the study showed that the concentration ranges of PCBs were higher inside all the schools compared to outside the schools. The samples, collected as inside/outside pairs between January 2012 and November 2015, revealed levels inside the schools were one to two orders of magnitude greater than outdoor air.

Exposure to PCBs through diet, inhalation or skin has been linked previously to cancer and developmental issues, with children being at an even greater risk.

"In some cases, inhaling air inside these schools could lead to higher exposure to PCBs than a child's diet," the researchers said in a press release. "And combined, the two sources are cause for concern."