What are EPAs drinking water regulations for dichloromethane?
EPA has set an enforceable regulation for dichloromethane, called a maximum contaminant level (MCL), at 0.005 mg/L or 5 ppb. MCLs are set as close to the health goals as possible, considering cost, benefits and the ability of public water systems to detect and remove contaminants using suitable treatment technologies. The Phase V Rule, the regulation for dichloromethane, became effective in 1994. The Safe Drinking Water Act requires EPA to periodically review the national primary drinking water regulation for each contaminant and revise the regulation, if appropriate. EPA reviewed dichloromethane as part of the Six Year Review and determined that the zero MCLG and 0.005 mg/L or 5 ppb MCL for dichloromethane are still protective of human health.
