Banned chemicals persist in deep ocean & food chain

walterbyrd writes: Scientists were surprised by the relatively high concentrations of pollutants like PCBs and PBDEs in deep sea ecosystems.

The authors of the study say that the deep ocean can become a "sink" or repository for pollutants.

They argue that the chemicals accumulate through the food chain so that when they reach the deep ocean, concentrations are many times higher than in surface waters.