The report appeared online Aug. 10 in Environmental Science & Technology, a peer-reviewed journal of the American Chemical Society, the worlds largest scientific society.
Polybrominated diphenyl ethers (PBDEs), which are used widely as flame-retardant additives in electronics and furniture, are released into the environment both at their manufacturing sources and through everyday product wear and tear, according to the researchers.
They measured PBDEs in 700 samples of farmed and wild salmon from around the world, including most major salmon-producing regions. The study, which is by far the largest of its kind, used the same samples from an earlier study that revealed significantly higher levels of organochlorine chemicals like PCBs and dioxins in farmed salmon than in wild.
With one exception, they report, all farm-raised samples had much higher levels of flame retardants than wild salmon. They also found that farmed salmon from Europe had higher levels than those from North America, and that both European and North American farm-raised salmon had higher levels than those raised in the southern hemisphere.
One surprising outcome of the study was that wild Chinook salmon from British Columbia had the highest average PBDE levels of all the samples. "Theres something about Chinook thats different, particularly with PBDEs," says the studys lead author, Ronald Hites, Ph.D., an environmental chemist at Indiana University. The elevated levels could be related to the Chinooks feeding behaviors, according to the researchers. Among all the wild species in the study, Chinook tend to feed higher in the food web and grow to b
Contact: Michael Bernstein
American Chemical Society