PCBs are toxic man-made organic chemicals that pose a threat to human health and to the environment.
The Environmental Protection Agency has classified PCBs as potential human carcinogens known to adversely affect the immune, reproductive, nervous and endocrine systems of humans and other animals. Used in U.S. industrial and commercial applications, PCBs were manufactured from 1929 until being banned in 1979. Because they are resistant to degradation, PCBs are still present in the environment.
