Cadmium in Drinking Water
EPA limits, health effects, and what to do if your water is affected.
🩨 Health Effects
Kidney damage from long-term exposure. Cadmium accumulates in the body over time. High short-term levels cause nausea and vomiting. Cadmium is a probable human carcinogen.
📍 Sources in Water
Enters water from corrosion of galvanized pipes (cadmium is an impurity in zinc), discharge from metal refineries, and runoff from hazardous waste sites and fields treated with phosphate fertilizers.
✅ What To Do
Replace galvanized pipes if possible. Use a reverse osmosis or distillation filter. Run water before drinking if pipes are old. Cadmium violations are relatively rare in community water systems.
📜 Regulation History
The EPA set the cadmium MCL at 0.01 mg/L in 1975, then lowered it to 0.005 mg/L (5 ppb) in 1991 under the Phase II rule based on updated kidney toxicity data. The WHO guideline is 0.003 mg/L, stricter than the US MCL.
🔬 How To Test Your Water
Certified lab tests for cadmium cost $15-$30. Home test kits specifically for cadmium are rare; a comprehensive metals panel from a lab ($50-$100) is the best option if you suspect cadmium. Homes with old galvanized pipes should test with a first-draw sample.
💧 Which Filters Remove Cadmium?
Reverse osmosis (NSF/ANSI 58 certified) removes 95%+ of cadmium. Distillation is also very effective. Ion exchange systems can reduce cadmium. Look for NSF/ANSI 53 certification for cadmium reduction if using a point-of-use filter.
Check your tap water for Cadmium
Search your ZIP code to see if your water system has had Cadmium violations, plus lead testing results and an overall safety grade.
Search your ZIP code →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.