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WaterQualityLens

Inorganic

1040

Nitrate

Causes methemoglobinemia ("blue-baby syndrome") in infants under 6 months. Carbon filters do NOT remove nitrate — reverse osmosis (NSF 58) only.

Maximum contaminant level
10 mg/L
Legal MCL
Enforceable federal limit
Health goal
10 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 Nitrate 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 Nitrate the enforceable limit and the health goal are the same number, 10 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 10 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 Nitrate under Inorganic for navigation; the grouping is ours, the limits are the regulator’s.

The record for Nitrate

Enforceable limit (MCL)
10 mg/L
Health goal (MCLG)
10 mg/L
Reporting unit
mg/L
Category
Inorganic
Contaminant code
1040

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 Nitrate

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 Nitrate, 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 Nitrate, and Standard 53 covers carbon-based reduction, which does not remove Nitrate. 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 Nitrate, 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 Nitrate. 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 Nitrate under NSF/ANSI 42. It would not count as verification of Nitrate 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 Nitrate under NSF/ANSI 372. It would not count as verification of Nitrate reduction in any case.

Counts are of active products in the WaterQualityLens filter registry holding a verified claim for contaminant code 1040 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 Nitrate.

Entity graph

Systems reporting Nitrate

Water systems in our coverage whose most recent published sample set includes Nitrate. Each value carries its sample date and the agency that reported it.

Certified reduction · commercial placements

Filters verified to reduce Nitrate

These filters hold an independent NSF/ANSI health certification (Standard 53, 58, or 401) specifically for Nitrate. 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 Nitrate; commercial arrangements never affect this list.