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WaterQualityLens

Inorganic

1041

Nitrite

Causes methemoglobinemia in infants; acutely dangerous. Removed only by reverse osmosis (NSF 58), not carbon filters.

Maximum contaminant level
1 mg/L
Legal MCL
Enforceable federal limit
Health goal
1 mg/L
Health goal (MCLG)
No known health risk
Category
Inorganic
Category
Reporting unit
mg/L
Reporting unit
Reverse osmosis required

Nitrate/nitrite cannot be removed by standard carbon-based pitcher, faucet, or under-sink filters (NSF/ANSI 42 or 53). Only reverse-osmosis systems certified to NSF/ANSI 58 (or specific ion-exchange systems) are effective. Standard carbon filters will NOT protect against this contaminant.

Regulatory basis

How Nitrite is regulated

What the enforceable limit actually obliges a utility to do, and how it differs from the health-based goal it is measured against.

For Nitrite the enforceable limit and the health goal are the same number, 1 mg/L. EPA set the Maximum Contaminant Level (MCL) at the health goal (MCLG), so there is no feasibility gap here: meeting the legal limit also means meeting the health-based goal. A value above 1 mg/L is both an exceedance of the goal and a violation of the enforceable standard.

Results are reported in mg/L. A laboratory result and the limits above are only comparable when both are expressed in that same unit — a value in a different unit will be off by orders of magnitude. WaterQualityLens groups Nitrite under Inorganic for navigation; the grouping is ours, the limits are the regulator’s.

The record for Nitrite

Enforceable limit (MCL)
1 mg/L
Health goal (MCLG)
1 mg/L
Reporting unit
mg/L
Category
Inorganic
Contaminant code
1041

Limits as published by EPA and state primacy agencies. This page reports regulatory and certification records; it does not assess anyone’s exposure and makes no health prediction.

Certification scope

Which certifications actually remove Nitrite

Only NSF/ANSI 53, 58 and 401 are health-contaminant standards. A product certified only to Standard 42 (aesthetics) or 372 (lead-free materials) has not been verified to reduce Nitrite, however the box is worded.

  • NSF/ANSI 53

    Counts — health standard

    Health effects: lead, VOCs, cysts, chromium, and (post-P473) PFAS reduction.

    No filter in our registry holds a verified NSF/ANSI 53 claim for Nitrite, and Standard 53 covers carbon-based reduction, which does not remove Nitrite. Reverse osmosis certified to NSF/ANSI 58 is the treatment that applies here.

  • NSF/ANSI 58

    Counts — health standard

    Reverse osmosis: dissolved inorganics, arsenic, hexavalent chromium, and total PFAS.

    3 filters in our registry hold an independently verified NSF/ANSI 58 claim for Nitrite, listed below.

  • NSF/ANSI 401

    Counts — health standard

    Emerging/incidental compounds: pharmaceuticals and select trace contaminants.

    No filter in our registry holds a verified NSF/ANSI 401 claim for Nitrite. That means we hold no certification record — not that the standard could never cover it.

  • NSF/ANSI 42

    Does not count — not a health standard

    Aesthetic effects: chlorine, taste, odor, particulates. No health-contaminant protection.

    No registry product lists Nitrite under NSF/ANSI 42. It would not count as verification of Nitrite reduction in any case.

  • NSF/ANSI 372

    Does not count — not a health standard

    Lead-free materials (manufacturing content only). Not a water-treatment claim.

    No registry product lists Nitrite under NSF/ANSI 372. It would not count as verification of Nitrite reduction in any case.

Counts are of active products in the WaterQualityLens filter registry holding a verified claim for contaminant code 1041 under that standard, as recorded by the certifying body (NSF, WQA, or IAPMO). Certification is granted per contaminant, not per product: a filter certified to Standard 53 for one contaminant is not thereby certified for Nitrite.

Certified reduction · commercial placements

Filters verified to reduce Nitrite

These filters hold an independent NSF/ANSI health certification (Standard 53, 58, or 401) specifically for Nitrite. Certification against a health standard means an accredited lab verified the filter reduces this contaminant — a materials-only claim such as NSF 42 or 372 does not.

  • Frizzlife

    M800 Under-Sink Reverse Osmosis

    Verified Partner
    FZ-M800Under-sink RO$399
    NSF/ANSI 58

    Certified by NSF

  • AquaTru

    Classic Countertop RO

    Verified Partner
    AT-CLASSICCountertop RO$449
    NSF/ANSI 58

    Certified by NSF

  • Waterdrop

    G3P800 Under-Sink RO

    Verified Partner
    WD-G3P800Under-sink RO$549
    NSF/ANSI 58

    Certified by NSF

Hardware links are affiliate placements marked “Verified Partner.” Products appear here solely because they hold an independently verified NSF/ANSI health certification for Nitrite; commercial arrangements never affect this list.