Since releasing guidance pertaining to polychlorinated biphenyls (PCBs) in schools in September 2009, the EPA has performed research to better understand the sources, risks and the extent of exposure of PCBs within school buildings. The agency has focused on studying methods to reduce PCB emissions and the risk of exposure, and is now in the final stages of developing updated guidance on addressing PCBs found in schools. This guidance will contain revisions to already existing recommendations and will reflect updated advice focusing on risk reduction.
Polychlorinated biphenyls (PCBs) represent a group of organic chemicals that include 209 individual chlorinated biphenyls, referred to as congeners. In studies conducted on animals, PCBs have been found to cause cancer and a variety of noncancer adverse health effects associated with the immune system, reproductive system, nervous system, and endocrine system. Upon further research of these adverse effects, PCBs were banned in 1979 and are currently regulated under the Toxic Substances Control Act. Although the manufacturing and processing of PCBs is now banned, exposure still poses a real threat. Any products and building materials produced from the 1950s through the 1970s may still contain PCBs, and therefore have the potential of releasing these hazardous chemicals into indoor air.
School buildings, in particular, are at risk when it comes to exposure of PCBs. According to the US Department of Education, approximately 48,000 schools within the US were built between 1950 and 1984. Schools that were built even before the 1950s may have been renovated during the period between the 1950s and the 1970s, which puts an even higher number of schools at potential risk. These schools may contain electronics, fluorescent light ballasts, caulking and other building materials which may be sources for PCBs, and the EPA recommends that affected schools remove these products immediately.
Even after these primary sources are removed, certain materials and dust within the school buildings have the potential of absorbing PCB emissions and ultimately act as a secondary source for PCBs. Due to the existence of these secondary sources, the EPA further recommends conducting a deep cleaning of school buildings, including ventilation systems, to assure the removal of any PCB-containing dusts.
Little is still known about the transport and exchange of PCBs between the air, settled dust and other materials. It is crucial that Licensed Site Remediation Professionals (LSRPs) and their counterparts develop a careful approach for understanding, assessing and mitigating PCBs within schools. LSRPs must familiarize themselves with the latest research on the potential sources of PCBs, as well as state and federal guidance regarding recommended methods of assessment and remediation for PCBs in school buildings and child care facilities.
For more information on polychlorinated biphenyls: https://www2.epa.gov/region8/polychlorinated-biphenyls-pcbs
For current EPA interpretive guidance pertaining to PCBs: https://www.epa.gov/solidwaste/hazard/tsd/pcbs/pubs/guidance.htm
For more information on caulk containing PCBs in schools: https://www.epa.gov/pcbsincaulk/caulkschoolkit.htm