"Federal authorities are urging schools across the U.S. to replace the electrical components in older light fixtures to reduce the threat of contamination from potentially cancer-causing chemicals.

In nonbinding recommendations released Wednesday, the Environmental Protection Agency says many schools built before 1979 use light fixtures that contain polychlorinated biphenyls, a manmade chemical that can affect the immune system and reproductive system and can cause cancer if they build up in the human body.

The agency urges schools to replace the electrical components in the light fixtures to prevent the escape of PCBs into the air. If the chemicals do leak, they would not represent an immediate threat but could present health concerns if they persist over time, the EPA says. "

Tennille Tracy reports for the Wall Street Journal December 29, 2010. [2]