What is chromium? And what is it doing in my water?

Chromium is a naturally occurring element that becomes an issue in drinking water in the form of Chromium 3 and Chromium 6, which are typically generated in industrial processes. Chromium 6 – or hexavalent chromium – was made notorious in the movie “Erin Brockovich” where a major utility was held liable for contaminating water supplies with the chemical.

Chromium 6 is widely considered to cause cancer, and to affect the respiratory system, kidneys, liver, skin and eyes. It does not belong in your water.

Authorities do not agree on what level of Chromium 6 is acceptable or safe. There are studies underway. The current federal drinking water standard for total chromium is 0.1 mg/l or 100 ppb. (Parts per billion.)