ClearWaterContaminants › Arsenic

Inorganic

Arsenic in Drinking Water

EPA limits, health effects, and what to do if your water is affected.

EPA Limit (MCL)
0.01 mg/L
mg/L
Category
Inorganic
Data Source
EPA SDWIS
Updated quarterly

🩨 Health Effects

Long-term exposure is linked to skin damage, circulatory problems, and increased risk of bladder, lung, and skin cancer. Arsenic also affects the nervous system and can contribute to diabetes. The EPA lowered the MCL from 0.05 to 0.01 mg/L in 2001 in response to cancer evidence.

📍 Sources in Water

Arsenic occurs naturally in rock and soil and dissolves into groundwater, making it most common in private and small community wells. Mining operations, agricultural pesticides, and industrial discharge can also elevate levels. Naturally high concentrations are found in parts of the Southwest, New England, and upper Midwest.

✅ What To Do

Use a point-of-use reverse osmosis (RO) filter or activated alumina filter, both rated NSF/ANSI 53 for arsenic removal. Boiling water does not remove arsenic. Check your utility's Consumer Confidence Report for measured levels.

Check your tap water for Arsenic

Search your ZIP code to see if your water system has had Arsenic violations, plus lead testing results and an overall safety grade.

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Data from the EPA's Safe Drinking Water Information System (SDWIS). MCLs reflect minimum federal standards; some contaminants may pose health risks below these thresholds.