The cancer-causing chemical made famous in the movie "Erin Brockovich" is finding its way into drinking water in Northwest Indiana -- likely at many times the level California scientists consider safe, according to a new report.
Some warn about dangers and blame Northwest Indiana's steel mills, which discharge thousands of pounds of chromium into Lake Michigan, the source of drinking water for most of the region's residents. Others say the chromium comes from natural sources and may actually be good for you.
The report by the Environmental Working Group shows levels of chromium in tap water in Lake County averaged 16 to 41 times what California authorities recently suggested is a "safe" level for "bad" chromium.
However, the Northwest Indiana numbers include both "good" and "bad" chromium, and they're still within the range that the U.S. Environmental Protection Agency considers safe for drinking.
EPA only requires water utilities to test for total chromium, a combination of the "good" chromium (chromium-3) and "bad" chromium (chromium-6, also known as hexavalent chromium.) Good chromium is an essential nutrient often found in multivitamins that regulates glucose metabolism. Bad chromium is carcinogenic.
"It's difficult to draw conclusions because they're saying we should have hexavalent chromium at a certain level, but we're not really testing for that, so it's hard to say where we are and what's safe. That's the big discussion taking place now," said Mark LeChevallier, director of innovation and environmental stewardship for American Water nationwide.
EPA has set a tap water standard of 100 parts per billion for both kinds of chromium combined.
In Northwest Indiana, the highest level measured in the last six years was 35.4 parts per billion in Cedar Lake, according to the Environmental Working Group. That's well below the 100 part standard set by EPA, but nearly 600 times the 0.06 parts per billion that California recommends is safe for "bad" chromium.
Indiana American Water -- which delivers water to Gary, Burns Harbor, Chesterton, Hobart, Merrillville, Portage, Porter, South Haven, Schererville, Crown Point, Lake Station, New Chicago and Ogden Dunes -- has detected chromium in its water only twice since 1999. That was in 2003, when tap water levels were 11 parts per billion in Gary and 10 in Ogden Dunes, said company spokesman Joe Loughmiller.
"We've had no detections of total chromium at any of our operations in Indiana last year," he said.
The utility's detection limit for combined "good" and "bad" chromium is 7 parts per billion, so anything below that would not show up in tests, he noted.
"We're detecting total chromium, which is good and bad -- or might be all good, who knows?" LeChevallier said.
To the Environmental Working Group, that's exactly the question. The group has criticized EPA for not setting a legal limit for "bad" chromium in tap water despite a September 2010 review by EPA scientists that said the metal is "likely to be carcinogenic to humans."
"At least 74 million Americans in 42 states drink chromium-polluted tap water, much of it likely in the cancer-causing hexavalent form," the Working Group said in its report. "Given the scope of exposure and the magnitude of the potential risk, EWG believes the EPA should move expeditiously to establish a legal limit for chromium-6 and require public water suppliers to test for it."
EPA said its standards are as protective of human health as science warranted when the rules were made.
"EPA's regulation assumes that the sample is 100 percent chromium-6," EPA said in a Jan. 11 press release. "This means the current chromium-6 standard has been as protective and precautionary as the science of that time allowed."
No chromium was found in Porter County, according to the report, but the group said that doesn't mean there isn't chromium-6 in the water, only that it wasn't found above the detection limit, said Leeann Brown, a spokeswoman for the Environmental Working Group.
The report is based on two types of data: Samples taken by volunteers in big cities, including Chicago, tested only for bad chromium. And water quality reports of both good and bad chromium by local utilities averaged over a five-year period and weighted by population, she said.
Unclear if NWI levels are bad
In Chicago, tap water samples showed "bad" chromium levels were 0.18 parts per billion -- about three times California's "safe" level. But there's no way to tell how large a share of the chromium found in Northwest Indiana is "bad" chromium, Brown said.
"We can't answer these questions for the nation. We need EPA to do it. From the little we know, this is where we could be finding it," she said. "There's no way to give someone (using) a small utility the answers they need. We need someone to step in and require testing and require that this information be articulated to the people buying this water."
Complicating the matter is that the metal transforms back and forth between good and bad chromium, LeChevallier said. Your stomach can process some, but not all, chromium-6, and chromium in surface water like Lake Michigan can transform when it reacts with oxygen in the air.
"It changes between those two forms," LeChevallier said. "What is the measurement in water, how stable it is, whether these low levels stay chromium-6 when you ingest it and it goes through your stomach, it's very complex. It's hard to know that what you're measuring is, in fact, having health effects ... That's kind of why EPA is looking at this and taking its time to review the health effects."
Mills blamed for chromium
Chromium-6 can pollute water through erosion of soil and rock. But it also gets into water supplies after being discharged from steel and pulp mills and metal-plating facilities. That has led some to blame Northwest Indiana's steel mills for chromium levels in drinking water from Lake Michigan.
The EPA's Toxics Release Inventory shows that U.S. Steel and ArcelorMittal's four locations in Lake and Porter counties discharged a combined 3,100 pounds of chromium in 2009.
The closest source to Chicago's water intake is ArcelorMittal Indiana Harbor West in East Chicago, which discharged 1,000 pounds of chromium about 10 miles from the intake. ArcelorMittal Burns Harbor is the farthest away, about 25 miles.
"We'd expect to see higher chromium if there's a discharge from steel mill factories and the like in the area ... The reasons in Illinois would be hard to say, although we know from EPA they're planning much further investigation into this chemical," said Brown of the Environmental Working Group.
EPA vowed at the end of December to find out how widespread the problem is. On Jan. 11, the agency issued enhanced monitoring guidance recommending where utilities should collect samples, how often they should be collected, and what analytical methods should be used for testing.
That should give consumers more information on how much "bad" chromium is in drinking water, how it transforms and how current treatment methods affect levels of bad chromium in drinking water, EPA said.
LeChevallier said some chromium comes from industries, but he didn't think mills are the source in Northwest Indiana.
"The low levels we're finding in the water are probably not coming from industrial effluent. They're coming naturally from the soils," he said. "The Environmental Working Group targeted groundwater supplies because that comes from the soil. We rarely find this in surface water supplies because oxygen can react with chromium."
The Indiana Department of Environmental Management reduced the amount of "bad" chromium that the mills can discharge when it recently renewed their wastewater permits.
Remove it yourself
LeChevallier said his own family drinks tap water from American Water in New Jersey and that he's not worried because levels of chromium are below the standard EPA set as protective.
Eric Rosenthal, senior vice president of marketing at Culligan water, agreed that most or all municipal water systems are safe to use. However, for those who are worried about it, water systems using reverse osmosis can take remove hexavalent chromium, he said. Stores such as WalMart and Meijer sell water in bulk from such a Culligan system.
Buying your own reverse osmosis system costs $700 and up, he said. It's possible to rent water treatment systems, which cost at least $10 a month. But regular water filters such as Brita won't do the trick, he said.
"We would not use a pitcher or a faucet-mounted filter to take chromium-6 out," he said. "You need ... a more sophisticated water purification process," he said.