Dioxin Pollution

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  • Topic: Polychlorinated dibenzodioxins, Agent Orange, Vietnam War
  • Pages : 9 (1141 words )
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  • Published : October 8, 1999
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Dioxin is one of the most toxic chemicals known.

A report released for public comment in

September 1994 by the US Environmental

Protection Agency clearly describes dioxin as a

serious public health threat. The public health

impact of dioxin may rival the impact that DDT

had on public health in the 1960's. According to

the EPA report, not only does there appear to be

no "safe" level of exposure to dioxin, but levels of

dioxin and dioxin-like chemicals have been found

in the general US population that are "at or near

levels associated with adverse health effects." The

EPA report confirmed that dioxin is a cancer

hazard to people; that exposure to dioxin can also

cause severe reproductive and developmental

problems (at levels 100 times lower than those

associated with its cancer causing effects); and

that dioxin can cause immune system damage and

interfere with regulatory hormones.

The International Agency for Research on Cancer

[IARC] --part of the World Health Organization

--announced February 14, 1997, that the most

potent dioxin, 2,3,7,8-TCDD, is a now

considered a Class 1 carcinogen, meaning a

"known human carcinogen."

Dioxin is a general term that describes a group of

hundreds of chemicals that are highly persistent in

the environment. The most toxic compound is

2,3,7,8-tetrachlorodibenzo-p-dioxin or TCDD.

The toxicity of other dioxins and chemicals like

PCBs that act like dioxin are measured in relation

to TCDD. Dioxin is formed as an unintentional

by-product of many industrial processes involving

chlorine such as waste incineration, chemical and

pesticide manufacturing and pulp and paper

bleaching. Dioxin was the primary toxic

component of Agent Orange, was found at Love

Canal in Niagara Falls, NY.

(http://www.enviroweb.org/issues/dioxin/index.html)

The major sources of dioxin are in our diet. Since

dioxin is fat-soluble, it bioaccumulates up the food

chain and it is mainly (97.5%) found in meat and

dairy products (beef, dairy products, milk,

chicken, pork, fish and eggs in that order... see

chart below). In fish alone, these toxins

bioaccumulate up the food chain so that dioxin

levels in fish are 100,000 times that of the

surrounding environment. The most conspicuous

source of dioxin pollution is from paper mills which

may pollute nearby streams with wastewater. Fish

living downstream from paper processing plants

have been found to contain significant amounts of

dioxin in their tissues.

In EPA's dioxin report, they refer to dioxin as

hydrophobic. This means that dioxin, when it

settles on water bodies, will avoid the water and

find a fish to go in to. The same goes for other

wildlife. Dioxin will find animals to go in to,

working its way to the top of the food chain.

Dioxin has been know to cause cancer in many

different cases such as in explosion at a

Hoffman-LaRoche chemical plant in Seveso, Italy,

in 1976. People did not have any signs of cancer

at first. So everyone said look at Seveso dioxin

does not cause cancer. Now a new study in the

journal EPIDEMIOLOGY reveals that people

exposed to dioxin during the Seveso explosion

have begun to exhibit excessive numbers of cancer

cases. Dr. Linda Birnbaum, director of

environmental toxicology for U.S. EPA now says

that this case is just another strike against dioxin.

The area around Seveso has been divided into

three zones, called A, B and R. The small A zone

was most heavily contaminated, but its 724

residents were evacuated. ("Heavy" contamination

means that each square yard of land contained 13

to 494 micrograms of dioxin; a microgram is a

millionth of a gram and there are 28 grams in an

ounce.) The B zone was less heavily contaminated

but its 4824 residents were not evacuated; zone B

contained 43 micrograms of...
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