Chlorine Dioxide (residual disinfectant)
disinfectant
Added intentionally by some water systems to control microbes and taste/odor.
EPA regulatory status
Legal limit (MCL)
0.8 mg/L
Goal (MCLG)
0.8 mg/L
MRDL (Maximum Residual Disinfectant Level) = 0.8 mg/L — a disinfectant limit, not an MCL. MRDLG = 0.8 mg/L.
Health effects
Can cause anemia; in infants and young children, nervous-system effects.
This is general public-health information, not medical advice — consult your physician with any health concerns.
National violations
466
EPA's enforcement data (SDWIS/ECHO) records 466 violations of Chlorine Dioxide (residual disinfectant)'s rule nationally.
How to remove Chlorine Dioxide (residual disinfectant)
Frequently asked questions
What is Chlorine Dioxide (residual disinfectant)?
Chlorine Dioxide (residual disinfectant) is a disinfectant regulated in US drinking water. Added intentionally by some water systems to control microbes and taste/odor.
What is the legal limit for Chlorine Dioxide (residual disinfectant) in drinking water?
MRDL (Maximum Residual Disinfectant Level) = 0.8 mg/L — a disinfectant limit, not an MCL. MRDLG = 0.8 mg/L.
What health effects does Chlorine Dioxide (residual disinfectant) have?
Can cause anemia; in infants and young children, nervous-system effects.
How many violations of Chlorine Dioxide (residual disinfectant) limits are on record nationally?
EPA's enforcement data (SDWIS/ECHO) records 466 violations of Chlorine Dioxide (residual disinfectant)'s rule nationally.
How do I remove Chlorine Dioxide (residual disinfectant) from my water?
Filter technologies certified to reduce Chlorine Dioxide (residual disinfectant) include: activated carbon (NSF/ANSI 42). 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