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Agorism
12-20-2010, 12:57 PM
Study finds large amounts of probable carcinogen in US water supply

http://www.rawstory.com/rs/2010/12/study-finds-large-amounts-probable-carcinogen-water-supply/


A recent study of the drinking water in 35 US cities found alarming levels of hexavalent chromium, a probable cancer-causing carcinogen.

Hexavalent chromium was the chemical at the center of events depicted in the film "Eric Brockovich."

The first nationwide analysis measuring the presence of chromium, carried out by the nonprofit Environmental Working Group, was made public on Monday.

Norman, Oklahoma had by far the highest measure at 12.9 parts per billion. Honolulu, Hawaii, Riverside, California and Madison, Wisconsin were other cities with high levels.

Of the 35 cities where measurements were taken, 31 showed traces showed traces of hexavalent chromium. Of those, 25 exceeded California's proposed 0.06 parts per billion limit.

The federal Environmental Protection Agency is considering whether to set a limit for hexavalent chromium in tap water. The agency is reviewing the chemical after the National Institutes of Health, deemed it a "probable carcinogen" in 2008.

Hexavalent chromium has long been known to cause lung cancer when inhaled, and scientists recently found evidence that it causes cancer in laboratory animals when ingested. It has been linked in animals to liver and kidney damage as well as leukemia, stomach cancer and other cancers.

A widely used industrial chemical until the early 1990s, hexavalent chromium is still used in some industries, such as in chrome plating and the manufacturing of plastics and dyes. The chemical can also leach into groundwater from natural ores.

In 1993, Erin Brockovich was successful in bringing the high levels of hexavalent chromium in Hinckley, California into the national spotlight. PG&E paid 600 townspeople more than $300 million to settle a lawsuit brought by Brockovich.

The company was accused of leaking hexavalent chromium into the town's groundwater for more than 30 years.

"Our municipal water supplies are in danger all over the US," Brockovich told The Washington Post. "This is a chemical that should be regulated."

Read the full report from the Environmental Working Group.

The list of cities tested in this study follows:

Norman, Okla. - 12.9 ppb
Honolulu, Hi. - 2.00 ppb
Riverside, Calif. - 1.69 ppb
Madison, Wis. - 1.58 ppb
San Jose, Calif. - 1.34 ppb
Tallahassee, Fla. - 1.25 ppb
Omaha, Neb. - 1.07 ppb
Albuquerque, N.M. - 1.04 ppb
Pittsburgh, Pa. - 0.88 ppb
Bend, Ore. - 0.78 ppb
Salt Lake City, Utah - 0.30 ppb
Ann Arbor, Mich. - 0.21 ppb
Atlanta, Ga. - 0.20 ppb
Los Angeles, Calif. - 0.20 ppb
Bethesda, Md. - 0.19 ppb
Phoenix, Ariz. - 0.19 ppb
Washington, D.C - 0.19 ppb
Chicago, Ill. - 0.18 ppb
Milwaukee, Wis. - 0.18 ppb
Villanova, Pa. - 0.18 ppb
Sacramento, Calif. - 0.16 ppb
Louisville, Ky. - 0.14 ppb
Syracuse, N.Y. - 0.12 ppb
New Haven, Conn. - 0.08 ppb
Buffalo, N.Y. - 0.07 ppb
Las Vegas, Nev. - 0.06 ppb
New York, N.Y. - 0.06 ppb
Scottsdale, Ariz. - 0.05 ppb
Miami, Fla. - 0.04 ppb
Boston, Mass. - 0.03 ppb
Cincinnati, Ohio - 0.03 ppb
Indianapolis, Ind. - not detected
Plano, Texas - not detected
Reno, Nev. - not detected
San Antonio, Texas - not detected

tangent4ronpaul
12-20-2010, 01:20 PM
Norman Okla (Cleveland County) is listed as follows:

http://statecancerprofiles.cancer.gov/cgi-bin/quickprofiles/profile.pl?40&001

Death Rate/Trend Comparison by Cancer, death years through 2007
Oklahoma Counties versus United States

All Cancer Sites
All Races, Both Sexes

Cleveland County's rate is similar to the rest of the US and is a stable trend.


San Antonio Tx (Bexar County)

http://statecancerprofiles.cancer.gov/cgi-bin/quickprofiles/profile.pl?48&001

Bexar County has a similar rate to the rest of the US and is a falling trend.

hmmmm....

might get a better pic by researching what cancers this chemical causes and drilling down on those.

Overall, the contamination doesn't look like it has much of an effect on cancer rates, but perhaps some.

-t

TNforPaul45
12-20-2010, 01:30 PM
A better question would be what is causing these levels so consistently across such a broad swath of the country. . .although a sample size of 35 is not a huge indicator of a problem.

tangent4ronpaul
12-20-2010, 01:35 PM
A better question would be what is causing these levels so consistently across such a broad swath of the country. . .although a sample size of 35 is not a huge indicator of a problem.

"A widely used industrial chemical until the early 1990s, hexavalent chromium is still used in some industries, such as in chrome plating and the manufacturing of plastics and dyes. The chemical can also leach into groundwater from natural ores."

short answer: manufacturing and strip mining.

-t

Zippyjuan
12-20-2010, 02:45 PM
Note the numbers- most are less than one part per billion- by comparision, if this was a disease, about one person in the entire world would have it. Zero point two parts per billion would not be considered a "large amount" but rather a barely measurable amount. That is one part in five billion.

Some interesting comparisons for one part per billion (and most of the reported levels in the list are one fifth or less of these amounts):
http://www.waterontheweb.org/resources/conversiontables.html

One-Part-Per-Billion
one 4-inch hamburger in a chain of hamburgers circling the earth at the equator 2.5 times
one silver dollar in a roll of silver dollars stretching from Detroit to Salt Lake City
one kernel of corn in a 45-foot high, 16-foot diameter silo
one sheet in a roll of toilet paper stretching from New York to London
one second of time in 32 years

sailingaway
12-20-2010, 02:55 PM
It is all in the dosage. I am not sure what the contamination pathway for hex chrome is beyond breathing so I don't yet have a take on this. But standard petroleum from underground tanks is usually left in place if it is 100 ppM (note parts per MILLION not ppb) whereas on the other hand the action level for dry cleaning solvent TCE is 5 parts per billion. It depends on how hazardous it is. Hex Chrome is bad to breath. I really have to see some toxicity level for drinking it. I'm not all excited over this at the moment, but the 12 ppb ranking probably wants to take a look at that. I wonder what ELSE is in that water, though, since it is a fairly industrial chemical, although often found in industrial paint.

And being from California, the fact that something is higher than a limit proposed here is nonpersuasive.

Other states typically use a 1 in 100,000 deaths from cancer with reasonable maximal exposure to evaluate; California often uses a one in a MILLION deaths with exposure measured by sitting naked in, up to the neck, and ingesting, and breathing the material -- for 70 years straight. And since grilled meat contains a 'carcinogen', I really take statements like this one with a grain of salt. I'm not saying it shouldn't be evaluated, just that I am waiting skeptically for the government's 'cure' to be propounded.....

Zippyjuan
12-20-2010, 03:14 PM
A bit of info from the EPA-
http://www.clu-in.org/contaminantfocus/default.focus/sec/chromium_VI/cat/Overview/

Chromium is abundant in nature. Its valence states range from -2 to +6, but in natural environments, it is generally found as trivalent chromium [Cr(III)] or hexavalent chromium [Cr(VI)]. Trivalent chromium occurs naturally in many fresh vegetables, fruits, meat, grains, and yeast and is often added to vitamins as a dietary supplement. Hexavalent chromium (CASRN 18540-29-9) is most often produced by industrial processes and may be an indicator of environmental contamination. This form exists in oxidizing conditions and can move down through soil to underlying groundwater. The concentration of naturally occurring chromium in U.S. soils ranges from 1 to 2,000 parts per million (ppm). Hexavalent chromium concentrations in air are generally low because it can react with dust and other air pollutants to form trivalent chromium and can be removed by atmospheric fallout and precipitation. In air, the concentrations generally range between 0.01 and 0.03 microgram per cubic meter (µg/m3). Drinking water levels are generally less than 2 parts per billion (ppb).

Hexavalent chromium can be toxic. When inhaled, it can damage the lining of the nose and throat and irritate the lungs. Based on studies of workers in chromium processing factories, hexavalent chromium is classified as a known human carcinogen due to chronic inhalation exposures. When swallowed, it can upset the gastrointestinal tract and damage the liver and kidneys, however evidence suggests hexavalent chromium does not cause cancer when ingested, most likely because it is rapidly converted to the trivalent form after entering the stomach.


The trivalent form of Chromium is considered an essential nutrient and as this piece points out is found in the soil and fruits and vegetables so if you are ingesting hexivalent chromium through your water, is it not likely being harmful or cancer causing. Inhaling it is when problems can occur.

There was a study which found hexivalent chromium causing cancer in rats, but that was at levels many times higher than what a human would consume from the most highly contaminated water.

Male and female rats and mice were given four different doses of sodium dichromate dihydrate in their drinking water ranging from 14.3 mg/l to 516 mg/l for two years. The lowest doses given to the animals in the study were ten times higher than what humans could consume from the most highly contaminated water sources identified in California.

The researchers report finding significant increases in tumors at sites where tumors are rarely seen in laboratory animals. Male and female rats had malignant tumors in the oral cavity. The studies conducted in mice found increases in the number of benign and malignant tumors in the small intestine, which increased with dose in both males and females.


http://www.sciencedaily.com/releases/2007/05/070516145447.htm