n Nitrosodimethylamine
N-Nitrosodimethylamine (NDMA) is a nitrogen-containing byproduct formed mainly during chloramine disinfection. It is unregulated federally but is on the EPA's contaminant candidate list and is the byproduct most often cited in the chlorine-to-chloramine 'regrettable substitution'.
Health Effects
Classified by IARC as probably carcinogenic to humans (Group 2A). It is detected at extremely low concentrations and is not federally regulated in drinking water, though several states set notification levels.
Common Sources
- Byproduct of disinfecting drinking water with chloramine
- Formed from reactions of chloramine with nitrogen-containing organic matter
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Where is n Nitrosodimethylamine Found?
n Nitrosodimethylamine has been detected above EPA health guidelines in 1 cities serving 0.2M people across the US.
Contaminant Type
n Nitrosodimethylamine is classified as a Disinfection Byproducts contaminant.
Related Disinfection Byproducts Contaminants
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