Environment: The Menace of PCB

• Share

(2 of 2)

Official Goof. Still, evidence of PCB pollution continued to crop up, probably because markets were already saturated with PCB products. In mid-August, FDA disclosed that it had seized more than 75,000 fresh eggs from wholesalers in Norfolk, Va., because the chickens that laid them had eaten feed containing the tainted fish meal. Though the agency assured the public that no tainted feod would leak out, it later admitted an official goof: a shipment of 60,000 eggs had somehow got through federal inspectors and, presumably, into the stomachs of Washington, D.C., residents.

Two weeks ago, the Department of Agriculture announced that "unacceptable levels of the poison PCB" had been found in turkeys processed by a Minnesota subsidiary of Swift & Co. About 50,000 birds were voluntarily withheld from the market while agriculture experts searched for the source of the contamination. Around the same time. Michigan Governor William Milliken ordered a halt to the commercial sale of coho salmon after PCB was found in salmon taken from Lake Michigan. Last week FDA disclosed that PCBs had also been found in several different kinds of dried foods, including baby cereals and shredded wheat. The PCB source has been traced to the cardboard packaging material, which was made partly of recycled PCB-treated copying paper.

PCBs are difficult to cope with for a number of reasons, first of all because the chemicals are hard to identify. They so closely resemble DDT they can be differentiated only by spectrographic analysis. PCBs are long-lived and, like DDT, their potency is multiplied as they work their way up the food chain. Unlike DDT, however, these chemicals are not sprayed but get into the environment accidentally, which makes them even harder to trace and control.

For all the grim warning signs, there is as yet no proof that PCBs at present low levels are harmful to humans. Most scientists, and critics like Congressman Ryan, however, feel that the safest course is to treat PCBs just as though they were the most potent of pollutants, until tests determine exactly what the long-term effects may be.