PCBs

PCBs are a group of manufactured organic chemicals that contain 209 individual chlorinated chemicals. These chemicals have been used widely as coolants and lubricants in transformers, capacitors, and other electrical equipment. Products that even today pose a PCB exposure risk include old fluorescent lighting fixtures and electrical appliances containing PCB capacitors.

There are a number of ways you or your unborn child could have been exposed to PCBs. These include:

Food: PCBs can be highly concentrated in fish. Predator fish at the top of the food chain, as well as bottom feeding fish, tend to contain the highest PCB levels in those waters.
Indoor Air: Older fluorescent lights found in schools, offices, and homes may still contain transformers or ballasts that contain PCBs. If the ballasts fail, PCBs can leak out and contaminate exposed surfaces and the air.
Surface Soils: A health hazard exists if a person swallows small amounts of the soil, or if the soil runs off to lakes and rivers, and the PCBs eventually accumulate in fish and other wildlife.
The Workplace: Industrial accidents have been responsible for most cases of acute PCB poisoning in humans.