Nitrite
Category: inorganic
EPA MCL
1 mg/L
Status
EPA Regulated
NSF Standard
NSF/ANSI 58
Health Effects
Same as nitrate - methemoglobinemia ('blue baby syndrome') in infants under 6 months. Nitrite is more acutely toxic than nitrate because it directly converts hemoglobin to methemoglobin.
Where It Comes From
Runoff from fertilizer use, leaching from septic tanks, sewage, erosion of natural deposits. Nitrite is a less stable form that can convert to/from nitrate in the environment.
Where It's Commonly Found
Same areas as nitrate contamination - agricultural zones, areas with septic systems. Less common than nitrate as a standalone contaminant because nitrite converts to nitrate readily.
Less commonly found at MCL-exceeding levels than nitrate. Combined nitrate + nitrite MCL is 10 mg/L.
How to Remove It
Effective Technologies
- reverse osmosis
- ion exchange
- distillation
Does NOT Remove It
- activated carbon
- carbon block
- UV
- KDF
- mechanical filtration
Official Sources
Related Contaminants
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Enter Your ZIP Code →Informational guidance based on EPA data and NSF standards - not medical advice.