Jensen Finds PCBs in Animal Tissues.

In December, 1966, New Scientist magazine published a short statement about a new chemical hazard in the environment. That chemical was polychlorinated biphenyl (PCB), and the author of the statement was Sören Jensen, a Swedish chemist from the University of Stockholm. He had been measuring pesticide residues in animal tissue for the Institute for Analytical Chemistry. Jensen found that PCBs were making some unidentified signals that interfered with his analysis. His conclusion was that PCBs were entering the food chain.