Hexavalent chromium (CrVI or Chromium 6) is a group of chemical compounds containing the element chromium that is odorless and tasteless. It is used in the production of stainless steel, textile dyes, wood preservation, leather tanning, and a variety of other applications. Hexavalent chromium is a probable carcinogen and was brought to national attention when it was found in the drinking water supply of the southern California town of Hinkley, and the subsequent involvement of Erin Brockovich.
The EPA is currently performing a comprehensive review of the adverse health effects of Hexavalent Chromium on humans. Chromium 6, if inhaled, has been known to cause lung cancer. Chromium 6 is a probable carcinogen, and has shown increased risk of gastrointestinal tumors (stomach cancer), leukemia, as well as kidney and liver damage when ingested by laboratory animals.
As of January 2011, the EPA has not established a safety standard for Chromium 6 in drinking water. The EPA currently only regulates the total Chromium found in drinking water supplies (this includes Chromium 3, which is found naturally in foods at low levels and is an essential human dietary nutrient). Maximum Contaminant Level (MCL) for Chromium set at 0.10 ppm (parts per million).
California has proposed, but not enacted, a MCL of 0.1 ppb (parts per billion) for Hexavalent Chromium.
The EPA has a list of water systems across the US, some provide online water quality reports and if they do not their contact information is provided.
National Testing Laboratories, Inc. in Ypsilanti has a five bottle testing kit, which is supplied by many water quality professionals across the nation. You simply follow the directions in the kit and return the sample to the lab. They test your sample and then report to you. Your test results will be a two page report showing contaminant level, a cover letter explaining the test results and what you should do.View Drinking Water Testing Kits from National Testing Laboratories
Faucet and countertop filters using activated carbon are not capable of removing or reducing Hexavalent Chromium. Water purification (reverse osmosis), not just simple filtration, will remove Hexavalent Chromium from drinking water. Systems with a NSF/ANSI Standard 58 seal are third-party certified to remove Hexavalent Chromium.
NSF/ANSI Standard 58: Reverse Osmosis Drinking Water Treatment Systems
Overview: This standard was developed for point-of-use (POU) reverse osmosis (RO) treatment systems. These systems typically consist of a pre-filter, RO membrane, and post-filter. Standard 58 includes contaminant reduction claims commonly treated using RO, including fluoride, hexavalent and trivalent chromium, total dissolved solids, nitrates, etc. that may be present in public or private drinking water.
The foregoing information was compiled from the 'Sources of Information' links above and brought to national attention recently by tests commissioned by the Environmental Working Group (EWG).