Specimen No. 0098
CautionSynthetichousehold chemical
Chlorine in Tap Water
chlorine water · chlorinated water · disinfection byproducts
Chlorine disinfects municipal water and prevents waterborne disease. However, it reacts with organic matter to form trihalomethanes (THMs) and haloacetic acids — which have regulatory limits due to cancer risk.
high confidence
Researched April 18, 2026Specimen 0098Chlorine in Tap Water
Concerns
- Trihalomethanes (THMs — chloroform, bromoform) are probable carcinogens formed as disinfection byproducts
- EPA regulates THMs at 80 µg/L — but "safe" threshold does not mean zero risk
- Chloramine (alternative disinfectant) also forms byproducts and is harder to filter
- Hot showers — steam inhalation of volatilized chlorine and THMs increases exposure [inference]
Regulatory flags
- ⚑Chlorination can form disinfection byproducts (THMs, HAAs) — some IARC Group 2B
- ⚑EPA regulates maximum contaminant levels for DBPs
Commonly found in
Tap waterShower waterSwimming poolsDrinking water
Sources & references
Last researched: April 18, 2026
Research disclaimer: This rating is based on available peer-reviewed research and regulatory assessments at the time of publication. It is not medical advice. Consult a qualified professional for personal health or skin concerns.
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