TapGraded

Mercury (inorganic)

metal

Erosion of natural deposits; discharge from refineries and factories; runoff from landfills and croplands.

EPA regulatory status

Legal limit (MCL)

0.002 mg/L

Goal (MCLG)

0.002 mg/L

MCL 0.002 mg/L (2 ppb). MCLG = 0.002 mg/L.

Health effects

Long-term exposure is associated with kidney damage.

This is general public-health information, not medical advice — consult your physician with any health concerns.

National violations

36,761

EPA's enforcement data (SDWIS/ECHO) records 36,761 violations of Mercury (inorganic)'s rule nationally.

How to remove Mercury (inorganic)

activated carbon

NSF/ANSI 53

How this works →

reverse osmosis

NSF/ANSI 58

How this works →

Frequently asked questions

What is Mercury (inorganic)?

Mercury (inorganic) is a metal regulated in US drinking water. Erosion of natural deposits; discharge from refineries and factories; runoff from landfills and croplands.

What is the legal limit for Mercury (inorganic) in drinking water?

MCL 0.002 mg/L (2 ppb). MCLG = 0.002 mg/L.

What health effects does Mercury (inorganic) have?

Long-term exposure is associated with kidney damage.

How many violations of Mercury (inorganic) limits are on record nationally?

EPA's enforcement data (SDWIS/ECHO) records 36,761 violations of Mercury (inorganic)'s rule nationally.

How do I remove Mercury (inorganic) from my water?

Filter technologies certified to reduce Mercury (inorganic) include: activated carbon (NSF/ANSI 53), reverse osmosis (NSF/ANSI 58). 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