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WaterSafety

Cyanide in Drinking Water

Inorganic Chemical · MCL: 200 ppb · 0 systems exceeding limit

Overview

Cyanide is regulated under the Safe Drinking Water Act with an MCL of 200 ppb. The EPA Safe Drinking Water program sets and enforces the maximum contaminant levels shown here.

Health Effects

Exposure to Cyanide above the MCL of 200 ppb may cause adverse health effects. Consult EPA fact sheets for detailed information.

Sources of Contamination

Cyanide can enter drinking water from natural deposits, industrial discharges, or other sources.

Treatment & Removal

Treatment methods for Cyanide include activated carbon filtration, reverse osmosis, and specialized media.

How to Remove Cyanide From Water

These filtration methods are effective for reducing Cyanide in drinking water:

Filter MethodEffectivenessCost RangeCertification
Reverse Osmosis (RO)High (varies)$200-500 (under-sink)NSF/ANSI 58
Activated Carbon BlockModerate (varies)$30-100 (pitcher/faucet)NSF/ANSI 53
Reverse Osmosis (RO) — details

Reverse osmosis is effective against most dissolved contaminants. Check specific certifications for this contaminant.

Activated Carbon Block — details

Effectiveness varies by contaminant. Look for filters specifically certified for this substance.

Water Systems with Cyanide Detected