The Truth About PCBs (Part 2)

In 1964, a Swedish researcher named Soren Jensen discovered a group of mysterious chemicals while studying DDT levels in human blood. The chlorine-based compounds were so similar to dichlorodiphenyltrichloroethane (DDT), a chlorinated hydrocarbon insecticide, that Jensen spent the next two years developing new chemical tests. During the course of his research, Jensen began to worry about the extent of environmental contamination from these unknown pollutants. Even hair samples taken from his wife and children showed traces, with the highest levels in his infant daughter, who was still nursing. Although Soren Jensen eventually identified these mysterious compounds as chlorinated biphenyls, he admitted that he "didn't have the faintest idea where such compounds were used in society." Later, after ordering samples from a German chemical manufacturer, Jensen identified the DDT-like pollutants as polychlorinated biphenyls (PCBs), industrial chemicals that were often used as electrical insulators.

During the 1960s, the international scientific community learned, in the words of Soren Jensen, that PCBs "bioaccumulate along the food chain". PCBs, which take years to degrade, pass through the lipid portions of cell membranes and are absorbed into mammalian fat tissue. Although Jensen's first study focused on fish, the Monsanto Corporation became concerned enough to send several company executives to Sweden in 1968. While meeting with Jensen, they obtained a copy of an unpublished document which described his analytical method for detecting PCBs in the environment. Later that year, 1,300 residents of Kyushu, Japan were sickened by eating rice-bran oil that was contaminated with PCB fluids. When workers at a Westinghouse factory in Bloomington, Indiana expressed their concerns about working with PCBs, the plant manager allegedly "washed his hands and face in what he told workers was liquid PCBs to convince them not to worry."

Between 1969 and 1971, there were at least nine major incidents in which food products were contaminated with polychlorinated biphenyls. Although Monsanto continued to refute scientists' claims about the toxicity of PCBs, the chemical company quietly drafted a pollution abatement plan with several options. After rejecting calls to either do nothing or immediately discontinue the manufacture of PCBs, company executives chose a third way. The "Responsible Approach", as the plan was called, required Monsanto to express some environmental and public-health concerns, but to continue the manufacture and sale of PCBs. Moreover, customers would be required to sign indemnity agreements that held Monsanto harmless from future liability. Although Monsanto also agreed to sell PCBs only to customers who used them in "totally enclosed systems", it would continue to market PCBs in products that came into direct contact with food.

In the United States, PCB production peaked in 1970 at 85 million pounds.

Editor's Note: Part 1 of this series ran last week, right here on CR4.

Resources:

https://www.clearwater.org/news/timeline.html

http://www.hercenter.org/facilitiesandgrounds/pcbs.cfm