Dr. Marcham was part of the 9-member team that wrote this paper. Polychlorinated biphenyls (PCBs) are a group of man-made chemicals associated with a potential risk to human health and the environment. They were used in many building materials, particularly caulking, grout, expansion joint material and paint, from approximately 1950 to 1978. Both the U.S. Environmental Protection Agency (EPA) and the Agency for Toxic Substances and Disease Registry (ATSDR) have published extensive material evaluating human health impacts from exposure to PCBs. The apparent public health risks, including developmental effects in children, reproductive effects and long-term risks for cancer development, have driven consideration for actions, including further research into chronic health effects, mechanisms of contact, and assessing actual and potential exposures, both in public and commercial buildings, and in the workplace, where direct and incidental exposures may occur.