What we need to know
By Zarin Hussain, MPH (c) and Derek G. Shendell, D. Env., MPH
Grasping the use of PCBs
PCBs or polychlorinated biphenyls have been a public health threat for decades. PCBs were commonly used as insulators in materials from the 1920s to 1970s and, consequently, in the construction of many schools. This may now lead to higher exposure of PCBs among students and staff members.
Most schools were constructed in the 1950s-1980’s. Studies show that children have higher exposure, in part, because they spend most of their time in school. Researchers have estimated no less than 12,960 schools up to as many as 25,920 schools in the U.S. were built using caulk and sealants containing PCBs. About 46% of U.S. schools were constructed using PCBs and can be found in materials such as tiles and walls.
Other materials used in building schools such ballasts of fluorescent lights may contain PCBs. For example, the electrical components of fluorescent lights contain PCBs in their capacitors and potting material of the ballast for insulation.
People are often exposed through inhalation or physical contact with PCB oil or materials contaminated with PCBs after ballasts age and leak. According to lab and field studies, internal/external caulking increases indoor air concentration of PCBs. Notably, PCBs build up in dust settling on surfaces such as heating systems and ceiling panels. The materials used to build schools were correlated to increased inhalation exposure to PCBs in schools due to materials utilized in the construction of schools, surface treatments, and paints.
Notably, the oldest parts of school facilities usually have the highest concentrations since they were built in the period PCBs were popular. Moreover, materials such as sealants, paint, adhesives, and PCB volatilization from these materials increase excess PCB levels in indoor air exceeding acceptable EPA levels.
Exposure effects and prevention
Frequent cleaning of surfaces is crucial to prevent PCB exposure through the buildup of particles such as dust in buildings. Notably, for exposure among younger school-aged children, toxins and toxicants including lead often accumulate in such dust. Ventilation systems must be regularly cleaned as well to mitigate high PCB levels on dust in the air.
Teachers are also considered high-risk groups for exposure. For instance, inhalation exposure occurs through migration of PCBs from contaminated buildings or outdoor areas, often resulting in higher concentrations of PCB substances. The most common way for exposure to PCBs among staff and students is through inhaling dust contaminated by caulk and electrical components in lights.
Susceptible, vulnerable subgroups include younger children because they spend most of their time in school, including on the floor for group activities or nap time and during physical education classes. Thus, custodians should effectively clean surface dust. For instance, in a window frame that contains deteriorated caulk that reached the floor, it is crucial to use a HEPA vacuum to clean the areas.
The brains of children are growing rapidly, they ingest higher amounts of food per pound, breathe at higher rates, and have higher rates of metabolism. Furthermore, children spend approximately 35 to 50 hours in facilities for schools per week. For instance, children are more likely to ingest dust by engaging in behaviors such as crawling and playing on the ground before eating. Furthermore, children of women who were exposed to PCBs often are born prematurely and have higher incidents of low birth weight.
Notably, among adults, PCBs have been correlated to endocrine disruption and cancer. In addition, exposure to high concentrations of PCBs potentially induces lowered function of the liver, rashes, headaches, nausea and vomiting.
The long-term impact of PCBs includes nervous system damage, inhibited immunity, issues with the respiratory tract, interference of hormone levels and damage to the reproductive systems Short-term impacts of exposure to PCBs include eye irritation and skin irritation, such as chloracne. Pregnant women or women who are nursing and exposed to PCBs potentially pass them to infants, who potentially experience impairments in short-term and recognition memory (visual), and movement.
Summing it up
Primary sources of PCBs often lead to higher levels of exposure, especially if they are indoors due to substances such as caulk, paint, waterproofing sealants, adhesives and other coatings found in places such as around window frames, on walls, in expansion joints, and base and floor tiles. PCBs are also found in fluorescent light ballasts, in which the risk of exposure occurs if the seal is opened and PCBs leak into air or on dust.
Secondary sources of PCBs migrate from primary sources to materials used for construction nearby. For instance, there have been 99,000 ppm in brick, concrete, foam board, mortar and other building materials near primary sources.
Finally, PCBs also transport from both primary and secondary sources to media indoors such as dust, soil, air, and other media.
Dr. Derek Shendell is a professor at the Rutgers School of Public Health where Zarin Hussain is working toward her master’s degree in public health, majoring in environmental health sciences. They worked in coordination with the New Jersey Work Environment Council to produce this article.
What can local associations do
Employees should report any identified hazard immediately to prevent future work-related illnesses to their employers and your union representative. If the reported unsafe working condition is ignored, work with your union representative and union health and safety committee. Locals should also request the use of HEPA filter-containing vacuums, especially when cleaning dust potentially containing PCBs.
The local association should create, expand, and/or enhance their health and safety committee to oversee issues including removal of identified old sources of PCBs.
Resources and references recommended
Environmental Science and Pollution Research International
“PCB Remediation in Schools: A Review”
Reviews on Environmental Health
“Exposure to and health effects of volatile PCBs”
U.S. Environmental Protection Agency
Polychlorinated biphenyls (PCBs)
Environmental Health
“Mitigation of Building-Related Polychlorinated Biphenyls in Indoor
Air of a School”