Monsanto PCB Litigation: Environmental Claims and Exposure Cases

Polychlorinated biphenyls are a separate matter from glyphosate, though both trace back to Monsanto. PCBs were manufactured from 1935 until Congress banned domestic production in 1979. They persist in the environment for decades, and the litigation over them runs on a different track from the Roundup docket.

Two kinds of PCB case

The first is environmental: municipalities and states suing over contamination of waterways, sediment and stormwater systems, seeking the cost of remediation. The second is personal injury: claims brought by people exposed to PCBs in buildings — most often schools built or renovated during the decades when PCB-containing caulk and light ballasts were standard.

The 2016 verdict

A jury found against Monsanto in a PCB exposure case, one of the first to reach verdict on the personal injury theory rather than the environmental cost-recovery theory. The distinction matters: cost-recovery suits turn on statutes like CERCLA and state environmental law, while exposure suits turn on ordinary product liability and failure-to-warn doctrine.

Why the cases persist

Internal documents produced in discovery have been central to the plaintiffs’ theory that the manufacturer understood the persistence and toxicity of PCBs well before production stopped. Because PCBs do not break down readily, exposure claims continue to arise from buildings and sediment contaminated decades ago, which is why a substance banned in 1979 still generates active litigation.