Posted on 05/07/2008 9:23:28 PM PDT by kingattax
Decades after most countries stopped spraying DDT, frozen stores of the insecticide are now trickling out of melting Antarctic glaciers. The change means Adélie penguins have recently been exposed to the chemical, according to a new study.
The trace levels found will not harm the birds, but the presence of the chemical could be an indication that other frozen pollutants will be released because of climate change, says Heidi Geisz, a marine biologist at Virginia Institute of Marine Science in Gloucester in the US. She led a team that sampled DDT levels in the penguins.
She worries that glaciers could release an alphabet soup of chemical pollutants into the ocean, including PCBs and PBDEs industrial chemicals that have been linked to health problems in humans.
"DDT is not the only chemical that these birds are ingesting and it is certainly not the worst," Geisz says. Trickle-down pollution
Chemists first synthesised DDT (dichloro-diphenyl-trichloroethane) in 1874, but the chemical wasn't used an insecticide until the 1940s. DDT spraying slashed malaria rates in many countries, but the chemical's environmental toll was starting to cause concern.
Rachel Carson's 1962 book, Silent Spring, brought these concerns to the general public, and described, amongst other things, how birds of prey exposed to high levels of DDT lay thin, easily cracked eggs.
In 1972, the US banned the pesticide, and the UK followed suit in 1984. Some countries still use DDT to fight mosquito-borne diseases such as malaria and dengue, but worldwide usage has plummeted from 40,000 tonnes per year in 1980 to 1,000 tonnes per year now.
DDT latches onto small airborne particles then migrates toward the poles. Geisz, who has worked in Antarctica since 1999, sought to gauge long-term changes in pollutants found in the continent's seabirds
(Excerpt) Read more at environment.newscientist.com ...
Maybe I wasn’t clear. Dr. Edwards strongly opposed the ban on DDT.
“Ill send money when they talk about putting in wells or a school!”
Lol and thanks for the info. So our social reformers have already outdone Hitler and Stalin combined when it comes to mass slaughter. Unfortunately they’re just getting started. With global warming they’ve politicized science, so there goes western civilization. The ethanol scam is way ahead of schedule in bringing back massive starvation in the third world (and maybe here), forty years after the green revolution turned the Malthusian “overpopulation” scare into a joke. And with what they’re doing to our educational system we may have the know-how to harness our energy resources when and if these clueless clowns get bored and decide to get out of the way.
Correction on the last sentence: ....we may NOT have the know-how ....
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