Chloroform in Drinking Water
EPA limits, health effects, and what to do if your water is affected.
🩨 Health Effects
Chloroform is the most common trihalomethane (THM) in drinking water. Long-term exposure is linked to liver damage and increased cancer risk. It is regulated as part of the total trihalomethane (TTHM) limit.
📍 Sources in Water
Chloroform forms during water chlorination when chlorine reacts with naturally occurring organic matter. It is a treatment byproduct, not a source contaminant. Levels are highest in surface water systems in summer.
✅ What To Do
Activated carbon filters (NSF/ANSI 53 certified) and reverse osmosis effectively remove chloroform. As part of the TTHM group, reducing total disinfection byproducts is the primary goal.
Check your tap water for Chloroform
Search your ZIP code to see if your water system has had Chloroform violations, plus lead testing results and an overall safety grade.
Search your ZIP code →Data from the EPA's Safe Drinking Water Information System (SDWIS). MCLs reflect minimum federal standards; some contaminants may pose health risks below these thresholds.