Disinfection byproducts · in your tap water
Cancer-linked chlorination byproducts (regulated)
Haloacetic acids form when chlorine reacts with organic matter in the water — same mechanism as TTHMs. HAA5 refers to the five federally-regulated acids (mono-, di-, tri-chloroacetic; mono-, di-bromoacetic). EPA limit is 60 ppb; EWG guideline is 0.1 ppb (600× stricter).
Tastes the same. Looks the same. The lab's the only way to know it's there.
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Every source below was checked to make sure the link works and backs the claim it's next to. These are the primary regulators and peer-reviewed studies — not our opinion.
The federal rules that set the TTHM (80 ppb) and HAA5 (60 ppb) drinking-water limits.
States the federal HAA5 MCL of 0.060 mg/L (60 ppb) and the five regulated acids.
Names the five HAA5 acids and the nine HAA9 acids monitored nationally.
Peer-reviewed basis for EWG's health guidelines; finds brominated byproducts the most carcinogenic.
Time-updated meta-analysis: long-term DBP exposure associated with bladder cancer (OR ~1.59).
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Get my free water report Book a free checkupThis page is general water-quality education, not medical advice. Health classifications and limits are attributed to the EPA, EWG, IARC, ATSDR/CDC, WHO and the cited studies. Contaminant levels vary by water system and home — the only way to know what's in your water is to test it. Prepared by SwiftPro Heating, Cooling & Plumbing.