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FilterScored

Contaminant · Water

Nitrate

EPA MCL 10 mg/L (as nitrate-nitrogen). 2 of the water filters we score hold an accredited NSF, WQA, or IAPMO certification to reduce Nitrate. A claim is not a certification.

What it is

If you are on a private well, especially in farm country, this is the one to put on your radar. Nitrate enters drinking water mainly from fertilizer runoff, animal manure, and septic systems, so it shows up most in agricultural areas and in wells. The catch is that it gives no warning - no taste, no smell, no color - so the only way to know is to test.

Why it matters

The EPA sets a maximum contaminant level of 10 mg/L (measured as nitrate-nitrogen) for drinking water, and that regulatory threshold is the reference point we work from. What we score is whether a filter is certified to reduce nitrate, not any health outcome. One practical heads-up before you shop: standard carbon filters and most pitchers do not remove nitrate at all.

What removes it

What works is reverse osmosis (NSF/ANSI 58) or an ion-exchange system certified for nitrate reduction. This part is worth underlining: a typical carbon pitcher or faucet filter does NOT reduce nitrate, so the thing to check is certification for nitrate specifically - the filter type alone will not tell you.

Reference: EPA National Primary Drinking Water Regulations; nitrate MCL 10 mg/L.

Scored filters certified for Nitrate

FAQ

Does a Brita or carbon pitcher remove nitrate?
No - and this is a common and understandable assumption to get wrong. Activated-carbon pitchers and faucet filters simply are not designed for nitrate. What you need instead is a system certified to NSF/ANSI 58 (reverse osmosis) or a certified nitrate-selective ion-exchange filter.
Does boiling remove nitrate?
No, and it actually backfires: boiling concentrates nitrate as water evaporates rather than removing it. Use a certified reverse-osmosis system instead.

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