Water, Water Everywhere… Chromium 6Posted: December 25, 2010
Back in 2000, I got a video of a movie that had been released the year before. It involved a strong willed, single woman who was determined to make some sort of living to support her 3 kids. She began working for a law firm and while opening a new client file, she came across documents that eventually lead to the largest settlement ever paid for a hazardous/toxic waste lawsuit brought against a corporation. That movie was based on a real life hero, Erin Brockovich and many of you have probably seen it. If not, here is a series of clips from that film. Take a look and then continue reading the post. The video clips will sort of set up the discussion.
The recent release of data from the Environmental Working Group (EWG), a not for profit agency, which tested the tap water of 35 cities in the United States, is disturbing and alarming. Of the 35 cities tested, 31 of the cities test results came back positive for the very same toxic chemical that caused the various cancers of the Hinkley population, which Brockovich worked so hard to bring to court.
Chromium is a metallic element that is formed naturally, and there are several types of chromium. The kind of chromium that has been found in 31 cities within the US is Hexavalent Chromium or Chromium-6. Chrome 6 is a toxic substance that has been known to be extremely dangerous since the 1920’s. This carcinogenic is usually produced by industrial process and the US is one of the leading producers of Hexavalent Chromium. Manufactures use Chrome 6 for its anti-corrosive properties, tanning leather, metal plating objects, wood stains, textile dyes, and stainless steel. Chrome 6 is also a by-product of other kinds of industry like welding, or smelting, it is even found in some forms of concrete.
The real problem with Chrome-6 is its incredibly mobile in water, because of the level of water solubility of this gray metal. According to the National Toxicology Program (NTP), one of the compounds of Hex Chrome causes cancer in the form of malignant tumors. These tumors are formed in the oral cavity and small intestine of the test subjects in higher frequency as the doses of Chrome 6 are increased.
It has also been shown to cause cancer of the lungs when the substance is inhaled, and skin lesions and dermatitis when the chemical comes in direct contact with the skin. This direct contact can be in the form of liquid water, contaminated soil or air, making this type of exposure more common in the workplace. However, when you think of other ways to come in contact with this chemical it becomes more frightening. For example, if a home has Hex Chrome in its tap water, people are not only getting the internal exposure of the carcinogenic when they drink the water, cook with the water, etc. They are getting the direct contact of touching the chemical in showers, and other cleaning activities. And because the chemical can be inhaled in steam vapors, this makes taking those showers, or even washing dishes, life threating.
For an in depth discussion of Hexavalent Chromium I highly recommend these following articles in PDF format.
The only certified way to remove Hexavalent Chromium is by reverse osmosis filters. EWG has some information regard filters. They recommend the whole house be filtered because toxic Chrome 6 has multiple ways of exposure, as I described above. Whole house systems can run anywhere between $3,000 to $14,000 depending on how many gallons per hour it cleans. One of the problems with revers osmosis filters is the amount of time it takes for the water to go through the proces of filtration. Another thing to think about, as the EWG report shows is the fact that bottled water companies are not required to publish their water quality test results. EWG has found 38 containments in 10 popular bottle water brands.
So now that you have the basic understanding of what Chromium 6 is…I will discuss the EWG reports findings and the response from the EPA.
Red dots indicate EWG’s test sites and measured hexavalent chromium concentrations in parts per billion (ppb). Size of dot reflects the level found. Brown-shaded areas represent population-adjusted average concentrations of total chromium by county, calculated from EWG’s national tap water database (see Study Methodology).
Chromium 6 is not regulated in drinking water at the federal level. That means that there is no rules as to the minimum amount of Chrom 6 in the tap water of your local utility or well. Some states require monitoring of Hex Chrome, California being the one state that has set a standard of water quality. California’s limit for Hex Chrome found in drinking water is 0.06 ppb(Parts per billion.) For some perspective, the toxicology levels of Hinkley, California were at levels of 580 ppb, which is no where near the highest level of Chrome 6 that was found in Norman, OK. The city of Norman had levels of 12.90 ppb. However, when you consider that the limit for Hex Chrome in California is 0.06 ppb, you can see that Norman’s numbers are still cause for alarm.
This week the following articles were published: Hexavalent chromium health risks
Usually when someone tells us, “Don’t drink the water,” it’s because we’re headed to the airport destined for some third-world country where they don’t have a solid water purification infrastructure. Unfortunately, a recent study by The Environmental Working Group (EWG) suggests that people might want to consider avoiding the water in at least 31 major U.S. cities because of hexavalent chromium, sometimes called chromium-6, contamination in the municipal water supplies. Find a list of the affected cities here on The Lookout, a Yahoo! News Blog by Bret Michael Dykes.
What’s the Risk?
The EWG report found levels ranging as high as 12.9 ppb in the drinking water samples they tested. Only one city, Norman, Oklahoma had this level, the next highest was only two ppb found in the drinking water of Honolulu, Hawaii. In all, 31 of 35 cities had hexavalent chromium contamination in their drinking water at various levels. These concentrations are far below the levels that caused so much harm in the Erin Brockovich case, but they are higher than levels that have proven to be safe. It is likely that the risk involved with the concentrations found in the EWG study present a very low risk, but these levels have not been proven to be safe.
The Bottom Line on Hexavalent Chromium Contamination in Drinking Water Any industrially produced carcinogen in public drinking water supplies is too much, however, at present, the risk is likely to be low for those cities identified in the EWG report. Those that are concerned can take measures to mitigate their own exposure to hexavalent chromium in drinking water through a properly certified filtration or purification system.
EPA Must Limit Hexavalent Chromium in Drinking Water
However, the fact that such high levels of this dangerous chemical were found to be so widespread in the drinking water of cities spread across the country strongly suggests that the EPA needs to establish a legal limit for the amount of hexavalent chromium that can be present in drinking water and needs to require municipalities to test for it regularly.
COMMENTARY | Since the Environmental Working Group issued a report showing that the toxic chemical hexavalent chromium was found in the drinking water of 31 of the 35 cities they tested, journalists and environmentalists alike, including myself on both counts, have criticized the EPA for not having in place a strict limit for hexavalent chromium in drinking water and not requiring municipalities to test for the carcinogen on a regular basis. Yesterday, several hours after my story on the topic was published I received a tersely worded e-mail statement from the EPA defending their policy. Read my previous article on the EWG hexavalent chromium study here.
The statement which was released as a public press release is reprinted here in its entirety:
EPA Statement on Chromium-6 in Drinking Water
WASHINGTON – Today, EPA issued the following statement and background information in response to a study released on December 20, 2010 by the Environmental Working Group:
“EPA absolutely has a drinking water standard for total chromium, which includes chromium-6 (also known as Hexavalent Chromium), and we require water systems to test for it. This standard is based on the best available science and is enforceable by law. Ensuring safe drinking water for all Americans is a top priority for EPA. The agency regularly re-evaluates drinking water standards and, based on new science on chromium-6, had already begun a rigorous and comprehensive review of its health effects. In September, we released a draft of that scientific review for public comment. When this human health assessment is finalized in 2011, EPA will carefully review the conclusions and consider all relevant information, including the Environmental Working Group’s study, to determine if a new standard needs to be set.”
What journalists and the EWG said, however, remains true. Although the EPA does regulate total chromium, the standard is not broken down between the much less harmful trivalent chromium (chromium 3) and the more highly toxic hexavalent chromium (chromium 6). According to the existing standard, 100 parts per billion (ppb) of any combination of trivalent and hexavalent chromium in your drinking water is acceptable. That means that up to 100 ppb of the toxic carcinogen hexavalent chromium could be in your city’s drinking water without triggering any red flags.
A level of 100 ppb is uncomfortably close to the 580 ppb of hexavalent chromium found in the water of Hinckley, California, the town made famous by the Erin Brockovich movie. The residents of that town experienced an extraordinary rate of cancers and respiratory disorders that are linked to hexavalent chromium toxicity.
EPA Whitewashes Health Risks of Hexavalent Chromium
Read the EPA’s own 1992 toxicity report (updated in 2000) here. Although the EPA says that hexavalent chromium guidelines are being reviewed as part of their standard process, the document referenced in their defensive press statement yesterday says only this about the health effects of high levels of chromium (including hexavalent chromium) ingestion: “Some people who use water containing chromium (total) well in excess of the maximum contaminant level (MCL) over many years could experience allergic dermatitis.” In other words, if you drink too much for a very long time you might get a skin rash. Really? Although they are quick to follow up and say that statement is not meant to be a complete list of health effects, they don’t give any indication that the real effects may be much worse.
EPA Hiding More Serious Health Effects?
Admittedly, I’m not a doctor, but it’s hard to imagine some EPA official reading a report like that and deciding that, if they are only going to include one of the listed health effect in their overview, a possible skin rash (allergic contact dermatitis) is the one from that list that matters most to the American public. The cynical reader might conclude the EPA’s choice was intentionally made to downplay the real risks of hexavalent chromium.
Meanwhile, as the EPA mulls over what they should do, if anything, about regulating the amount of this poison that should be allowed in the drinking water your family receives from your municipal supplier, the EPA says that homeowners can effectively remove chromium “to below 0.1 mg/L or 100 ppb” using certified coagulation/filtration, ion exchange, reverse osmosis, or lime softening systems.
The EPA has extended the public comment time regarding the following report.
Toxicological Review of Hexavalent Chromium:
The draft Toxicological Review of Hexavalent Chromium provides scientific support and rationale for the hazard and dose-response assessment pertaining to chronic exposure to hexavalent chromium via ingestion.
Chromium is a naturally occurring element in the earth’s crust. The three main forms of chromium found in the environment are chromium (0), chromium (III), and chromium (VI), also known as hexavalent chromium. Chromium is widely used in manufacturing processes, and it can be found in many consumer products such as wood treated with copper dichromate, leather tanned with chromic sulfate, and stainless steel cookware. Chromium is released to the environment from natural and anthropogenic sources, with the largest releases occurring from industrial sources. The general population may be exposed to chromium by inhaling ambient air, and ingesting food and drinking water containing chromium. Dermal exposure to chromium can occur from skin contact with certain consumer products or soils that contain chromium.
Sep 1998 The oral RfD for hexavalent chromium was posted to the IRIS database. The inhalation RfC for hexavalent chromium and the carcinogenicity assessment for hexavalent chromium were also posted to the IRIS database.
May 2010 EPA initiated an interagency science consultation to review the draft toxicological review and charge to external peer reviewers.
Sep 2010 EPA released the external review draft for public review and comment and the interagency science consultation review draft with comments. EPA also announced a public listening session to be held on November 18, 2010. [Federal Register Sep 30, 2010]
Nov 2010 EPA extended the public comment period an additional 30-days. [Federal Register Nov 10, 2010]
Following the conclusion of the public review and comment period, public listening session, and external peer review, the draft Toxicological Review will be revised and submitted for a final Agency review and an EPA-led Interagency Science Discussion. As a last step, the final assessment will be posted on the IRIS database.
I hope that this post gives you lots to think about. My next post in this series will be focusing on the town of Norman, OK. I will be discussing the connection of the high amount of Hexavalent Chromium in the tap water and the aquifer that supplies the water to over 300,000 people, to the hazardous waste found at the EPA Superfund Site…Tinker Air Force Base.