By Anne Duffy
A recent study released by the Environmental Working Group lists Ann Arbor as one of 25 U.S. cities out 35 studied to have high levels of the cancer-causing hexavalent chromium (chromium-6) metal in its drinking water.
Chromium-6 was made famous in the movie “Erin Brockovich,” in which the town’s water of Hinkley, Calif., was poisoned with the substance.
“I feel like it’s dangerous. If it causes cancer, they really need to work on getting rid of the problem,” said Amy Comuth, 19, a Washtenaw Community College biology major from Ann Arbor.
And the problem is widespread. According to the EWG study released last month, tests found this cancer-causing chemical is in 89 percent of the cities sampled, with potentially millions of Americans drinking contaminated tap water.
Extremely high levels of the toxic metal were found in Norman, Okla., Honolulu, and Riverside, Calif.
EWG used EPA methodology 218.6, a very sensitive test, and the group tested the water samples specifically for hexavalent chromium, said company spokeswoman Leeann Brown.
Water utilities are only required to test for total chromium at this time, which includes trivalent chromium, a mineral that is used to metabolize sugar, and hexavalent chromium, the toxic metal that has been linked to stomach cancer, according to the Ann Arbor Water Treatment Services. There is no way to distinguish how much of which kind of chromium is in a typical water test conducted at these facilities.
“Tests for total chromium may come up negative, but that doesn’t mean there isn’t chromium-6 in the water,” said Brown.
The EWG’s study comes on the heels of the EPA’s Sept. 30 release of a toxicological review draft of hexavalent chromium by Integrated Risk Information System (IRIS), a human health assessment program that evaluates risk information on effects that may result from exposure to environmental contaminants, such as the toxic chromium.
While the EPA says on its website that it is taking a plan of action to address chromium-6 nationwide by first striving to understand its prevalence, citizens like Comuth remain concerned.
“Why is this everywhere?” she asked.
That’s a great question.
Hexavalent chromium is a byproduct of industry from steel and pulp mills, leather tanneries and metal-plating facilities. It can also naturally occur in soil erosion.
California, often the leader in setting environmental standards, has been working on setting a safety standard for chromium-6 in drinking water. On Dec. 31, California public health officials lowered the proposed public health goal for chromium-6 allowable in water from 0.06 parts per billion (ppb) to 0.02 ppb, according to EWG’s website.
EWG reported that Ann Arbor tap water had tested at a 0.21 ppb level of hexavalent chromium. With the new proposed goal, that would leave Ann Arbor’s contaminated drinking water at more than 10 times higher than the public health goal set by California. Yet local officials say there is nothing to fear.
“I am not alarmed by the EWG study that has come out,” said Molly Wade, manager of Ann Arbor Water Treatment Services.
According to Wade, the study didn’t involve water utilities in the testing. The water samples were taken from homes and businesses, not from the water leaving the water-treatment facilities.
“We don’t know how much of contamination could be coming from chromium fixtures,” said Wade.
Brown acknowledged the possibility of chromium coming from fixtures, but stated that in the EWG study the samplers let the cold tap water run for two minutes to clear any localized standing water that may contain stagnant chromium-6..
EWG chose to sample the water from homes and businesses instead of at the water treatment plant because they wanted to see what people were actually being exposed to when receiving the water from the tap.
The Ann Arbor water treatment plant uses a laboratory detection limit that is set at two ppb for total chromium, and the last three results were in compliance with the current, EPA standards (under 100 ppb) and deemed safe.
However, because Ann Arbor does not test specifically for chromium-6 and the detection is not as sensitive as the tests the EWG used, there is no way to know how much of the toxic metal the residents of Ann Arbor are drinking at the tap.
“We have the utmost confidence in our water and I can assure you we will continue to monitor (the chromium-6) problem and soon as the EPA releases guidance and if they recommend testing with certain methods, we will do that,” Wade added.
Meanwhile, some people are taking actions to prevent drinking contaminated water. Travis Bellow, 18, an undeclared WCC student from Belleville, used to work for the non-profit group Clean Water Action and uses a charcoal filter on his tap water.
“I don’t think our water is totally unsafe,” he said. “However, there are a lot of other contaminants, and it all adds up.”
Both Wade and Brown acknowledged that ordinary activated carbon filters, such as a Brita filters, do not significantly filter out chromium-6, but some reverse osmosis home filters do.
“Bottled water is not regulated as well as tap water and is usually not reverse osmosis, so it is not a good alternative to turn to either,” said Brown.
“(Chromium-6) is an industrial pollutant and it is naturally occurring and without action from the EPA and without the responsibility falling on the shoulders of the polluters, this problem is going to stay, despite how hard utilities try to overcome it,” she added.
As of yet, there is no word on when the EPA will implement a protocol of testing for chromium-6 for utilities.