Sulfate
EPA Secondary Standard
250 mg/L
A non-enforceable guideline set for taste, odor and appearance — not health. Water systems are not required to meet it.
What You May Notice
Above EPA's secondary standard, Sulfate can cause: salty taste.
EPA regulates Sulfate under a secondary drinking water standard — a non-enforceable guideline set for taste, odor and appearance rather than health. Water systems are not required to meet it, and exceeding it is an aesthetic problem, not a known health risk.
Source: EPA — National Secondary Drinking Water Regulations (retrieved 2026-07-27)
Is your Sulfate result safe? Get a free reading
The EPA Secondary Standard for Sulfate is 250 mg/L. Upload your water test (PDF or a photo) and we'll email a plain-English reading of where your result lands — and every other number — free. Educational only, no medical claims.
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Water filters certified under the following NSF standards are effective at removing Sulfate:
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Where is Sulfate Found?
Sulfate has been detected above EPA health guidelines in 5 cities serving 0.1M people across the US.
About the EPA Secondary Standard
EPA secondary standards (SMCLs) cover taste, odor, color and staining. They are guidelines, not enforceable limits, and exceeding one is an aesthetic issue rather than a known health risk.
Contaminant Type
Sulfate is classified as a Inorganics contaminant.
Related Inorganics Contaminants
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