What the HEX is Going on With our Drinking Water?
Getting to the bottom of a hot-button issue
I am sure many of you have seen the flood of recent headlines and articles posted all over newspapers, the Web and every news channel across the nation. The headlines are grim:
- 31 cities’ tap water has cancer-causing hexavalent chromium, study says;
- U.S. orders more testing of chromium-6 in tap water;
- High levels of chromium found in Chicago-area tap water;
- Advocacy group reports level of cancer-causing metal is three times as high as considered safe under a California proposal;
- Chromium-6 is widespread in U.S. tap water; and
- Cancer-causing chemical found in 89% of cities sampled.
Let’s dig into what chromium is, what it is used for and why it is being regulated.
Hexavalent chromium (chromium-6) refers to chemical compounds that contain the element chromium in the +6 oxidation state and also a metal found in natural deposits as ores containing other elements.
What is it Used For?
The most common uses of chromium are in many products and processes that include stainless steel, textile dyes, pigments for paints, paper and rubber, leather-tanning and anti-corrosion coatings. It can also be used in its soluble form in wood preservation. Chromium coatings usually are applied to aluminum, zinc, cadmium, copper, silver, magnesium and tin to prevent rust or other damage that can occur from exposure to oxygen.
Why is Chromium Being Regulated?
Chromium-6 has been known to cause lung cancer when inhaled, but scientists only recently found evidence that it causes cancer in laboratory animals when ingested. It has been linked in animals to liver and kidney damage, as well as leukemia, stomach cancer and other forms of cancer. For this reason, the U.S. Environmental Protection Agency (EPA) has determined safe levels of this chemical in drinking water, called Maximum Contaminant Level Goals (MCLGs). The MCLGs for total chromium have been set at 0.1 parts per million because the EPA believes this level of protection would not cause any of the potential health problems described above.
While there is currently no federal limit on the level of chromium-6 allowed in water, there is a maximum allowable limit of total chromium allowed in water. In 2009, however, California officials proposed setting a public health goal (PHG) for chromium-6 in drinking water of 0.06 parts per billion (ppb) to reduce the risk of cancer. This was their first step toward establishing a statewide enforceable limit. As recently as December 2010, the Office of Environmental Health Hazard Assessment (OEHHA) within the California EPA is announcing the availability of the revised draft technical support document for a proposed PHG for chromium-6 in drinking water. This document decreases the proposed PHG to 0.02 ppb and is available on the OEHHA website, www.oehha.ca.gov.
How Can Hexavalent Chromium be Removed From Water?
While treating the contamination at the source is the main goal of state and U.S. regulators, this has proven to be a very costly investment in time, resources and money; and it could potentially take years for the state and national regulators to agree on the allowable limits.
In the meantime, there are several products available with the technology to remove hexavalent chromium. The Water Quality Assn. (WQA) has many of them listed on its website, www.wqa.org. You can search the many certified product listings for the specific contaminant reduction of chromium-6. These products will carry the WQA’s Gold Seal and also will be listed under NSF/ANSI Standards 53 and 58.
Why Get Your Product Certified for Removal of This Contaminant?
With the growing concern of chromium-6 in groundwater around the country, many consumers are looking to certification agencies like the WQA for advice and products to ensure the water they consume on a daily basis is clean and safe from contaminants. Third-party certification offers many benefits to consumers and regulators, and shows that products can meet or exceed the industry standards set for performance and integrity—all while providing you with confidence and pride in your products.
What Does the Future Hold for Regulation?
While many agencies around the country will continue to talk about the many issues of chromium-6, and strict regulations have been put on its use due to airborne inhalation hazards, we do not know what the future will hold for regulations regarding chromium contamination of groundwater. Only time will tell as government agencies and lawmakers team with scientists and industry professionals to decide the best way to attack this harmful element. You can look to the WQA for breaking news and industry updates as they happen. Until then, make sure you have that final barrier between your water supply and your lips by going to www.wqa.org and checking out Gold Seal-certified products.