Unsafe levels of chromium-6, a carcinogenic chemical, have been found in the drinking water supplies of more than 200 million Americans in all 50 states, according to a report by the nonprofit Environmental Working Group.

Chromium is a naturally occurring element. While one form, chromium-3, is proposed to be an essential nutrient to the human body, chromium-6 is rare in nature and is typically associated with industrial sources, according to the National Toxicology Program.

It is used in steel production, chrome plating and to lower the temperature in electrical power plants’ cooling towers. The chemical is also present in the ash from power plants that burn coal.

EWG’s reports of chromium-6 testing in Bainbridge from 2013-2015 shows an average amount of 0.47 parts per billion (ppb) in the city’s drinking water. EWG states the health goal is 0.02 ppb, with the legal limit falling at 10 ppb.

The U.S. Environmental Protection Agency has not set a recommended health limit for chromium-6, yet chemical state scientists in California and elsewhere claim it can cause cancer when ingested even in small amounts.

In 2008, a two-year study by the National Toxicology Program found that chromium-6-laced drinking water caused cancer in rats and mice.

In 2010, the EPA ordered local water utilities to conduct tests for contamination of the chemical. More than 60,000 samples were taken across 31 cities in the U.S., finding chromium-6 in more than 75 percent of them. These findings show more than two-thirds of the population is drinking contaminated water, EWG reports.

“Americans deserve to know if there are potentially harmful levels of a cancer-causing chemical in their tap water,” said David Andrews, a senior scientist at EWG and co-author of the report. “But the test results on the EPA’s website are hard to find and even harder to understand. So we compiled and sorted the data, and we found that the scope of the contamination is startling. It’s long past time for the EPA to take action to protect Americans from chromium-6.”

A link to the data can be found online at thepostsearchlight.com.

Chromium-6 was the topic of the popular 2000 film “Erin Brockovich” starring Julia Roberts.