Jan. 10--Chromium-3 is an essential nutrient. Its evil twin, chromium- 6, is believed to cause ca ncer.
But consumer confidence reports that aim to educate the public about tap water quality do not distinguish between chromium-3 and chromium-6 -- the same pollutant made famous by Erin Brockovich in the desert town of Hinkley, the same pollutant that has been detected in public drinking water in San Joaquin County and across the nation.
Rather, the report that arrives in your mailbox by July 1 each year lists only the total amount of chromium.
"It's ridiculous, scientifically," said Gina Solomon, a senior scientist with the environmental group Natural Resources Defense Council. "You can't lump a known carcinogen in with a vitamin. It's sort of crazy."
And it may change, now that state officials have started a process that would lead to regulation, regular testing and reporting of chromium-6.
New year, new info
The state was supposed to come up with a mandatory standard for chromium-6 by 2004. That didn't happen.
But on New Year's Eve, officials released what's known as a "public health goal" -- a nonbinding, health-based ideal that is the first step toward a firm rule.
The health goal, .02 part per billion, is the threshold below which there is no known risk.
And yes, it's a very low number.
Imagine 20 drops of chromium mixed in with enough clean water to fill a string of railroad tank cars 10 miles long. That's roughly what .02 part per billion would look like.
How much chromium-6 is out there? It's hard to say, since sampling isn't mandatory.
Some local water providers did sample their wells for chromium-6 nearly a decade ago. Stockton found it as high as 4 parts per billion to 6 parts per billion, said Mark Madison, head of the city's Municipal Utilities Department.
That's 200 to 300 times the new public health goal.
But it's nowhere near levels seen in Hinkley, where chro-
mium contamination from that town's taps topped 580 parts per billion.
Madison said Stockton is waiting for further tests by the Environmental Protection Agency, which is considering a new federal chromium standard. The city has its own laboratory and samples for more than 100 substances.
"If it is demonstrated that the levels (of chromium-6) in our supply are posing a health risk, we will take all steps required to reduce to a point where it's safe," Madison said.
Goals vs. limits
It's not unusual for public water supplies to exceed health goals. Stockton's drinking water, from 2007 to 2009, exceeded goals for coliform bacteria, aluminum, radioactive substances and arsenic.
And yet, the city met all mandatory standards, which are usually much higher because they take into account the cost and technical feasibility of purifying the water.
Sometimes there's a huge gap between the goal and the rule.
The mandatory limit for total chromium, for instance, is 2,500 times higher than the new health goal for chromium-6.
"It's night and day," said Ross Moilan, whose California Water Service Co. delivers water to residents in central Stockton. His company, in the past year or so, has started testing for chromium- 6 in anticipation of coming regulations.
However, falling short of a stringent health goal doesn't make the water unsafe, officials say.
The goals are based on a lifetime's exposure. If the health goal for chromium-6 was achieved, you could drink a halfgallon of water for 70 years and even then would face a cancer risk of only 1 in 1 million, experts say.
In short: Higher chromium-6 levels mean greater risk, but they are not an immediate threat.
Public disclosure
Madison defends the right-toknow reports distributed each yea r.
"Health standards are dynamic," Madison said. "They change. And they're not becoming less stringent -- they're becoming more stringent."
When rules for chromium-6 are written, he said, an accounting of the heavy metal will begin appearing on the yearly reports.
Solomon, the environmentalist scientist, said the reports are great for regulated contaminants. But the EPA hasn't set many new standards, so the information hasn't been updated.
"There are so many things that have been popping up in drinking water in recent years that are not regulated ... that these reports are starting to get a little less reliable and a little out of date, and that's a shame," she said.
Contact reporter Alex Breitler at (209) 546-8295 or abreitler@ recordnet.com. Visit his blog at recordnet.com/breitlerblog.
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