[CINC] Study Finds Chemicals in Brains of Marine Mammals

[Deb4nb at aol.com]

Informative article:
Debra
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Study Finds Chemical Cocktail in Brains of Marine Mammals

(Beyond Pesticides, May 27, 2009) A recent, extensive study which 
investigated a variety of different chemicals, including organochlorine pesticides, 
in animal tissues reveals that marine mammals harbor high concentrations of 
hazardous chemicals in their brains. The results lay the groundwork for 
understanding how environmental contaminants influence the central nervous system 
of marine mammals.
The study entitled “_Organohalogen contaminants and metabolites in 
cerebrospinal fluid and cerebellum gray matter in short-beaked common dolphins and 
Atlantic white-sided dolphins from the western North Atlantic_ 
(http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VB5-4W3874X-1&_user=10&_rdoc=1&
_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&
_userid=10&md5=d4200c7e86ea8fd76f0d55f4f52d5ae2) ” is the first of its kind 
to find toxic chemicals in the brains of marine mammals. The study 
identified several contaminants including organochlorine pesticides like DDT, 
polychlorinated biphenyls (PCBs) and flame retardants in the cerebrospinal fluid 
and cerebellum gray matter of several species of marine mammals including the 
short-beaked common dolphins, Atlantic white-sided dolphins and the gray 
seal. PCBs were found in alarmingly high concentrations. Researchers found 
parts per million concentrations of PCBs in the cerebrospinal fluid of a gray 
seal. 
“We found parts per million concentrations of hydroxylated PCBs in the 
cerebrospinal fluid of a gray seal. That is so worrisome for me. You rarely find 
parts per million levels of anything in the brain,” remarked researcher, 
Eric Montie, PhD. 
Dr. Montie, lead author of the study, performed the research in 
collaboration with Mark Hahn and Chris Reddy of the Woods Hole Oceanographic 
Institution (WHOI) and Robert Letchre of Environment Canada. 
“We don’t really know the effect of that level in these animals,” he says. 
“The first step was just to see if these chemicals were present in the 
brain. And they are. So how do you monitor that? And that’s something we’re 
trying to develop methods to see if these chemicals do have neurotoxilogical 
effects,” says Dr. Montie. 
Dr. Montie plans to find out how these chemicals might impact marine mammal 
health. This summer, Dr. Montie will partner with scientists from NOAA to 
test the hearing in dolphins living near a Superfund site in Georgia and 
compare it to dolphins from locations where ambient concentrations of pollutants 
are significantly lower. The researchers view their work as the forefront 
of a new field of research, something that might be called 
neuro-ecotoxicology. Previous studies have been focused on how concentrations of marine 
pollutants affected the animal’s immune system or its hormone systems, however, 
the authors of this study say their results indicate that contaminants in the 
ocean can affect the neurological development of marine mammals. 
DDT, which is currently banned in much of the world, has been shown to 
cause cancer and reproductive toxicity. While _an overall reduction_ 
(http://www.beyondpesticides.org/dailynewsblog/?p=351)  in contaminant levels in 
coastal waters of the U.S., studies have found DDT and other persistent pollutants 
in Arctic animals like whales, penguins, seals and birds. However, new 
concern over the concentrations of these chemicals in the oceans arise as DDT, 
its metabolites and other persistent organic pollutants, including PCBs and 
PBDEs are being released at high levels in _melting glaciers_ 
(http://www.beyondpesticides.org/dailynewsblog/?p=344) , further threatening the health of 
marine animals. In 2007, the National Oceanic and Atmospheric Administration 
(NOAA) and the Environmental Protection Agency (EPA) _reported_ 
(http://www.beyondpesticides.org/dailynewsblog/?p=19)  extremely high concentrations of 
the pesticide DDT in fish caught in California’s Los Angeles county waters. 
According to the survey, the fish caught in the area contain the world’s 
highest-known DDT concentrations. 
Source: _Science Daily_ 
(http://www.sciencedaily.com/releases/2009/05/090520122227.htm) 
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