LOS ANGELES (AP) — California regulators voted Wednesday to establish a drinking water limit on hexavalent chromium, a toxic chemical compound made infamous by the movie “Erin Brockovich.”

The rule is the first in the nation to specifically target the heavy metal, known as chromium-6, and is expected to reduce the number of cancer and kidney disease cases from long-term ingestion, state officials say.

The proposal was unanimously passed by the State Water Resources Control Board, though it needs approval from the Office of Administrative Law to take effect.

The standard could inspire other states to adopt their own. More than 200 million Americans are estimated to have the chemical compound in their drinking water, according to an analysis of federal water testing data by the Environmental Working Group, a nonprofit research and advocacy organization.