To investigate the phenomenon, the EPA announced today (Sept. 27) that it would continue its collaboration with Indiana University Bloomington environmental scientists Ronald Hites and Ilora Basu to study the toxin's circulation between the air and the Great Lakes. What the scientists learn will help the EPA determine whether new PCB clean-up policies are needed.
"We saw a surprising trend a few years ago," said Hites, Distinguished Professor in IU's School of Public and Environmental Affairs. "The concentrations of PCBs began increasing at most sites and then started decreasing again. We still don't know why this happened, but we hope the next few years of data will provide us with some answers."
The EPA will give Hites and Basu $3.5 million to operate the U.S. portion of the Integrated Atmospheric Deposition Network for five more years. As part of their duties, the scientists will measure atmospheric levels of PCBs (polychlorinated biphenyls), PAHs (polycyclic aromatic hydrocarbons which result from incomplete combustion), PBDEs (polybrominated diphenyl ethers which are widely used as flame retardants), and chlorinated pesticides such as DDT. IU scientists have been running IADN with the EPA and Environment Canada since 1994.
The EPA released data last month showing that elevated PCB levels have led to fish consumption advisories for all five of the Great Lakes, and for many rivers and lakes in or near the Great Lakes Basin. Advisories do not necessarily prohibit fish consumption, but they usually caution consumers to severely limit their consumption of fish caught in tainted waters.