Now researchers report concentrations of airborne PCBs inside schools. Some students inhaling the compounds at higher levels than they would consume through their diets. Exposure through both are lower than set limits, but cumulative amounts, researchers caution, could be concerning.
PCBs (polychlorinated biphenyls) group of synthetic chemicals used in industries. Dumped waste containing the compounds into rivers and streams. PCB contamination is high in the Housatonic River and New Bedford Harbor in Massachusetts
EPA has calculated exposure levels for evaluation that are intended to maintain overall. PCB exposures below the oral reference dose (RfD) of 20 ng PCB/kg body weight per day. An RfD is an estimate of a daily exposure to the human population that is likely to be without an appreciable risk of harmful effects during a lifetime.
Studies have linked exposure either through diet, inhalation or skin contact with a range of health problems, including developmental issues and cancer. Children are at greater risk for potential health effects from the compounds than adults because they’re still developing. So, University of Iowa researchers wanted to see how much PCBs children were being exposed to in schools.
Evaluating exposure Levels for PCBs in School Indoor Air
The researchers tested the air inside and outside of six schools. Four were within 1.5 miles of the Indiana Harbor and Ship Canal, a waterway serving major industries in the area. Despite this source of PCBs to outdoor air for some schools, the analysis found that the concentration ranges of PCBs were higher inside all the schools than outside.
But below the current U.S. Environmental Protection Agency’s recommended action level of 500 ng/m3. The PCB fingerprint showed that the sources of the compounds varied across schools, suggesting a combination of historical contamination and new paint as contributors.
The schools were part of a study of human exposure to PCBs led by Peter Thorne. The study also estimated that in some cases, inhaling air inside these schools could lead to higher exposure to PCBs than a child’s diet. And combined, the two sources are cause for concern, the researchers say.