> > ... TCDD can alter gene expression of cells,
> > especially those that are growing or differentiating
>
> http://www.youtube.com/watch?v=3DJDdzr7KTZ8Y
Traces of Agent Orange are found in food in Vietnam
bmj.bmjjournals.com/cgi/content/full/327/7414/521-b?ck=3Dnck
Dioxin from Agent Orange, sprayed by the US military during the
Vietnam war, is still poisoning Vietnamese people today, 30-40 years
after spraying ended, says Dr Arnold Schecter of the University of
Texas School of Public Health, Dallas.
He, along with an international research team, collected samples of
animals used for food from Bien Hoa City, 35 kilometres north of Ho
Chi Minh City (formerly Saigon). Results of their study are re****ted
in the August issue of the Journal of Occupational and Environmental
Medicine (2003;45: 781-8).
"Even in children never sprayed with Agent Orange, dioxin is getting
into the Vietnamese people through highly contaminated foods,
including duck, chicken, and fish," said Dr Schecter.
The Agent Orange herbicide, containing tetrachlorodibenzop-dioxin
(TCDD), was sprayed in Vietnam between 1962 and 1971, primarily as a
defoliant. Typical blood concentrations of TCDD among Vietnamese
people are 2 ppt (parts per trillion), but concentrations as high as
413 ppt were found in Bien Hoa City.
High TCDD concentrations were found in children born many years after
spraying with Agent Orange ended and in migrants from parts of Vietnam
where Agent Orange wasn't sprayed. Extremely high concentrations in
soil samples=97over 1 million ppt=97and in sediment were found in some
nearby areas, such as Lake Bien Hung.
Usual TCDD concentrations in food are less than 0.1 ppt, yet the
researchers found concentrations in ducks up to 331 ppt wet weight, in
chickens up to 15 ppt wet weight, and in fish up to 66 wet weight, or
550 ppt in lipids.
High concentrations of polychlorinated biphenyls (PCBs) of unknown
source and dicophane (DDT) and its metabolites were found in some food
samples, and a wide range of measurable levels of
hexachlorocyclohexanes and hexachlorobenzene were found.
The highest concentrations of TCDD were found in the fat of tested
animals=97an im****tant finding, because fat is considered a delicacy in
Vietnam.
Dr Schecter said that although most food in Vietnam is not
contaminated with dioxins, certain dioxin "hot spots" are highly
contaminated, and the high PCB concentrations add to the toxicity of
TCDD. In 1971 a spill from underground storage tanks at an airbase
near Bien Hoa City released thousands of litres of Agent Orange into
the environment.
To help people in Bien Hoa City and other hot spots, Dr Schecter and
colleagues recommend measures to supply uncontaminated food, along
with additional healthcare follow up and possible methods of
environmental restoration. They also urge further studies of the
effects on health of dioxins and other toxic chemicals among veterans
who served in the Vietnam war.
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