(CNN) – Report: Harmful chemical found in tap water of 31 U.S. cities Millions of Americans in at least 31 U.S. cities could be drinking tap water contaminated with the harmful chemical hexavalent chromium, according to a report released Monday by the non-profit Environmental Working Group. While the dangerous carcinogen, otherwise known as chromium-6, may … Continue reading Contaminated tap water: Is it in your faucet?