Police across the Lowcountry and state were warned Thursday to watch for pumper trucks possibly dumping PCBs after the banned, cancer-causing chemical was found in a sewer treatment systems in the Upstate and Columbia.

What is PCB?

Polychlorinated Biphenyl, a chemical compound once used as an insulator because it was highly resistant to heat and flame.

Banned in 1979 because it was found to cause cancer, as well as problems in the immune, reproductive, nervous and endocrine systems.

Does not readily break down and can cycle for long periods through air, water and soil. Has been found in snow and sea water in areas far from the point where it was released.

Can accumulate in leaves, plants, food crops, small organisms and fish.

Source: Environmental Protection Agency

The threat in the Lowcountry could be real, a clean water advocate said. If trucks illegally dumping are on the move to avoid being spotted, they could show up here next, said Gerrit Jobsis, of American Rivers. “That’s the biggest concern. The threat of it getting downstream in the water is very low because it’s a heavy material that sinks to the sediment.”

The S.C. Department of Health and Environmental Control is investigating the possibility of illegal dumping of PCBs after the compound was found in at least four Upstate sewage treatment plants last month and now in the sewer grease trap behind a Columbia restaurant.

“There is currently no known impact to public health associated with this matter,” DHEC spokesman Mark Plowden said about the discoveries. “Based on the information we have to date, the water is safe to drink, and there has been no known discharge to waterways.”

PCBs are man-made organic chemicals that were used for decades to insulate hundreds of types of manufacturing equipment such as electrical transformers. They were banned in 1979 after being demonstrated to cause cancer and a host of other health problems, according to the federal Environmental Protection Agency.

But they are “persistent” chemicals that don’t easily break down and still are found widely in the environment. Recent studies of dolphins in coastal Georgia uncovered some of the highest levels of PCBs ever found in the fat of a marine mammal.

The S.C. Department of Natural Resources has PCB warnings about eating fish in place for Upstate rivers that feed into the Marion-Moultrie lakes, the source of most of the drinking water in the Charleston area.

Reach Bo Petersen at 937-5744, @bopete on twitter or Bo Petersen Reporting on Facebook.