TTHM
Total Trihalomethanes (TTHM)
disinfection byproductSDWA code: 2950
EPA Limit (MCL)
80.000 ppb (0.08 mg/L)
Health Goal (MCLG)
Not set
Unit of Measure
mg/L
How concentrations are reported
Includes chloroform, bromodichloromethane, dibromochloromethane, and bromoform.
Health Effects
Long-term exposure: increased risk of cancer (bladder). Some evidence of reproductive effects.
How It Gets Into Water
Byproduct of drinking water chlorination; reaction of chlorine with organic matter
Official EPA Guidance
For authoritative information on Total Trihalomethanes (TTHM)in drinking water, visit the EPA's official resource page.
View EPA Guidance ↗