Mysterious California sea lion deaths linked to toxic synthetic chemicals

Scientists say animals with higher levels of DDT, PCBs and others in their blubber are more prone to cancer triggered by herpes

Sea lions in California had been dying of a mysterious cancer for decades. Now, scientists say they have finally uncovered the likely cause: toxic chemicals from industrial trash, pesticides and oil refinery waste.

A team of mammal pathologists, virologists, chemists and geneticists have concluded that sea lions with higher concentrations of DDT, PCBs and other chemicals in their blubber are more prone to cancer triggered by a herpes virus.