If PCB manufacturing was discontinued more than 30 years ago why is it considered a biological risk today?
PCBs are sturdy molecules and are difficult to destroy. The more chloride ions substituted on the molecule the more potent the compound. They concentrate as they are ingested up the food chain and are dangerous to the health of marine and aviary species. In man they are a known carcinogen. Recent studies performed in the Hudson River, the Inner Harbor and Baltimore and the Housatonic River in Western Massachusetts have identified a natural anaerobic bacteria which degrades PCB agents.
