Copper
metal
Corrosion of household copper plumbing and brass fixtures; erosion of natural deposits.
EPA regulatory status
Legal limit (MCL)
No numeric MCL
Goal (MCLG)
1.3 mg/L
No MCL — regulated as a treatment technique under the Lead and Copper Rule. Action level = 1.3 mg/L at the 90th percentile of tap samples. MCLG = 1.3 mg/L.
Health effects
Short-term exposure to elevated copper causes gastrointestinal distress (nausea, vomiting, cramps). Long-term exposure can cause liver or kidney damage; people with Wilson's disease are at greater risk.
This is general public-health information, not medical advice — consult your physician with any health concerns.
National violations
100
EPA's enforcement data (SDWIS/ECHO) records 100 violations of Copper's rule nationally.
How to remove Copper
distillation
NSF/ANSI 62
Frequently asked questions
What is Copper?
Copper is a metal regulated in US drinking water. Corrosion of household copper plumbing and brass fixtures; erosion of natural deposits.
What is the legal limit for Copper in drinking water?
No MCL — regulated as a treatment technique under the Lead and Copper Rule. Action level = 1.3 mg/L at the 90th percentile of tap samples. MCLG = 1.3 mg/L.
What health effects does Copper have?
Short-term exposure to elevated copper causes gastrointestinal distress (nausea, vomiting, cramps). Long-term exposure can cause liver or kidney damage; people with Wilson's disease are at greater risk.
How many violations of Copper limits are on record nationally?
EPA's enforcement data (SDWIS/ECHO) records 100 violations of Copper's rule nationally.
How do I remove Copper from my water?
Filter technologies certified to reduce Copper include: reverse osmosis (NSF/ANSI 58), distillation (NSF/ANSI 62). Look for a filter independently certified against the specific NSF/ANSI standard for this contaminant — general "reduces contaminants" marketing claims are not the same as a contaminant-specific certification.
Source: EPA National Primary Drinking Water Regulations · Data as of 2026-07-16