DBPs (disinfection byproducts — trihalomethanes, haloacetic acids)
Toxins · Chlorination byproducts
Moderate priority
What this is
Tradeoff with waterborne pathogen risk — disinfection saves lives. THMs are volatile and inhaled/absorbed during hot showers at magnitudes similar to drinking. Carbon-filter pitchers (Brita, etc) reduce THMs well. Source-water quality (surface vs groundwater) affects baseline DBP potential.
Mechanism
Formed when chlorine/chloramine disinfectants react with natural organic matter in source water; THMs (chloroform, bromoform) and HAAs; IARC possible-to-probable carcinogens; bladder/colorectal cancer associations
Dose & route
Activated carbon drinking water filter; shorter showers (volatile THM absorption via skin/inhalation)
Citations
- https://pubmed.ncbi.nlm.nih.gov/25711326/
- https://pubmed.ncbi.nlm.nih.gov/29684818/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC3223824/
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