What are Polychlorinated Biphenyls (PCBs)?
Polychlorinated Biphenyls (PCBs) are a group of organic chemicals consisting of carbon, hydrogen and chlorine atoms. PCBs are either oily liquids or solids that are colorless to light yellow, and up to 209 individual compounds can exist in PCB mixtures. In North America, PCB mixtures were sold under the Aroclor tradename. PCB mixtures are resistant to acids, bases, oxidation, hydrolysis, and temperature changes, making them excellent chemicals for industrial applications. Their chemical properties and physical stability led to wide spread commercial use as inks, dyes, and dielectric and coolant fluids in electrical equipment and in heat transfer fluids.
PCBs are highly carcinogenic chemical compounds and can cause birth defects. Global efforts to protect human health from PCBs has resulted in the commitment of 185 countries to prohibit the production of PCBs, prohibit the development of new applications using PCBs, and eliminate the use of PCBs in equipment by 2025.
Despite discontinued usage, PCBs are considered a persistent organic pollutant and found globally in air, soil, sediments, and water. Most people are exposed to PCBs by eating contaminated fish because PCBs can enter the hydrosphere and are then brought into the biosphere by microorganism ingestion. PCBs then bioaccumulate and biomagnifies through the aquatic food chain.
It is important to test for PCBs in water, soil, and sediments because of their persistency and known toxicity leading to long-term adverse health impacts.