ClearWaterContaminants › Nitrite

Inorganic

Nitrite in Drinking Water

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

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

🩨 Health Effects

Like nitrate, nitrite is most dangerous for infants under 6 months, causing methemoglobinemia. Short-term exposure is the primary concern. Nitrite is typically found at lower levels than nitrate since bacteria quickly convert nitrite to nitrate.

📍 Sources in Water

Comes from the same sources as nitrate: fertilizer runoff, animal waste, and septic systems. It can also form in water distribution systems when nitrifying bacteria break down chloramine disinfectants.

✅ What To Do

Do not give elevated-nitrite water to infants or use it to mix formula. Boiling concentrates nitrite rather than removing it. Use bottled water or reverse osmosis filtration for infant feeding.

Check your tap water for Nitrite

Search your ZIP code to see if your water system has had Nitrite 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.