Archive for December, 2010

December 27, 2010

The attached video gives and excellent overview of western US water laws and how they have had a negative impact on water supply.  the good news given is that there are some new solutions to this problem.

http://www.youtube.com/watch?v=LV3ZjORGwoI&p=ED2FC89AE6EFE8F8

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City of Atlanta water contains probable cancer causing chemical

December 27, 2010

This article appeared in the AJC last week.  While I question some of the scientific reasoning as presented in the article, the fact is that Chromium 6 can turn up in public drinking water and it is a known carcinigen.  Collected rainwater on the other hand has little or no chance of having this contaminant.  In the article I would have liked to see what the danger level for Chomium 6 is even though we’d all prefer the levels to be below detection limits.

By Jeffry Scott

The Atlanta Journal-Constitution

An environmental group that tested drinking water in the city of Atlanta found it contains hexavalent chromium, a chemical that the National Institutes of Health has described as a “probable carcinogen.”

The Washington-based Environmental Working Group said in a study released Monday that the level of the chemical in Atlanta’s water ranks 13th-highest among water systems it tested last spring in 35 U.S cities.

But water officials in Atlanta and metro Atlanta said Monday that the level of the chemical found in the city’s drinking water, .20 parts per billion, is well below the 100 parts per billion of “total chromium” in the water that the Environmental Protection Agency considers safe to drink.

The Environmental Protection Agency requires water utilities to test for and restrict the amount of “total chromium” in the water. The total chromium is the combined amounts of hexavalent chromium and trivalent chromium.

Hexavalent chromium, also known as Chromium 6 — the toxic chemical upon which a 1996 Pacific Gas & Electric multi-million dollar legal settlement, portrayed in the movie “Erin Brockovich,” was based — has been found to cause cancer in laboratory animals. Trivalent chromium, or “good chromium,” is a mineral also found in water that humans need to metabolize sugar.

Water officials in Gwinnett, Cobb and Forsyth counties said Monday that total chromium tests of their systems have consistently come up as “none detected.” Gwinnett’s water supply has consistently registered less than 25 parts per billion, said Neal Spivey, the county’s director of water production.

The EPA is still studying whether to lower the acceptable levels of Chromium 6 in the water supply. Last year, California proposed a goal for safe levels of .06  parts per billion of Chromium 6. That’s less than one third the amount of Chromium 6 found in the City of Atlanta’s drinking water.  If California does set a limit, it would be the first in the nation.

Rebecca Sutton, a senior  scientist with the Environmental Working Group, said Monday that researchers decided to test Atlanta’s water out of curiosity about the level of chromium. The city and metro area do not have “a history of high levels of total chromium” in water supplies, she said.

The scientist said utilities have resisted efforts to lower the current safety standards for Chromium 6 in drinking water because of the expense of filtering out chemicals that also occur naturally in water. She said EPA and industry research to determine what are unsafe levels of Chromium 6 is also incomplete.

Janet Ward, a spokeswoman for the Atlanta Department of Watershed Management, said the city’s water “undergoes more than 50,000 tests annually to screen for more than 150 potential contaminants” and issues an EPA-mandated Water Quality Report detailing the results of all required tests.

“But the city does not test for the presence of certain contaminants, such as hexavalent chromium, as such tests are not currently required,” Ward said. “Hexavalent chromium is one of 20 chemicals under EPA review for potential further regulation.”

No public water system in the state exceeds the acceptable EPA level of total chromium, said Brad Addison, manager of the Georgia Environmental Protection Division’s Drinking Water Program.

Clearing out contaminants

Rebecca Sutton, a senior scientist with the Environmental Working Group, suggests that people worried about the level of chromium in their water — both the “bad” hexavalent chromium and the “good” trivalent chromium — should consider using a reverse osmosis water purifier, which connects to a home water supply and removes scores of impurities, including arsenic, cyanide,