Scientists at the University of Iowa College of Engineering recently set out to investigate which types of polychlorinated biphenyl compounds (PCBs) could be detected in various parts of the home. Airborne PCBs, which are widely known to cause cancer, were found to be surprisingly common in kitchens.
PCBs are classified by the International Agency for Research on Cancer as human carcinogens, and the manufacturing of these harmful substances was banned in the United States in 1979. However, these chemicals are still being produced as byproducts and remain detectable in offices and schools. Furthermore, PCBs have been found to linger longer in the environment because they do not break down easily.
The current study was focused on the inside and outside of 16 homes in Iowa. The researchers measured concentrations of PCBs using polyurethane-equipped passive air samplers for six weeks from August of 2017 to October of 2017.
Neurotoxic PCB-47 and PCB-51, as well as PCB-68, were found in high concentrations. The study also revealed a link between levels of these chemicals and the year the house was built, with higher levels in more recent years.
When the experts tested stoves, floors, walls, and other areas in the household for PCB emissions, they established that the chemicals originated in the cabinets.
According to the researchers, the substances were most likely generated by the breakdown of 2,4-dichlorobenzoyl peroxide, a common ingredient in modern cabinet sealants.
This is the first time that this particular source of toxic chemicals in the home has ever been identified. Many other building materials such as paints, stains, and insulation can also release harmful chemicals into the air.