PCBs, or polychlorinated biphenyls, were dumped into the Hudson River between 1929 and 1977 in massive quantities. Used in industrial applications, they were considered chemically and thermally stable; meaning they would not easily break down. Not easily catching on fire, they were an ideal chemical to be used in a variety of industries. A PCB is any molecule having multiple chlorine atoms attached to the carbon atoms of a biphenyl (when two rings of 6 carbon atoms are attached to each other) nucleus.

Explore this site to find out more about the history of the dumping, the dangers of PCBs, cleanup options, and links to more information.