HAA9
HAA9 is the sum of nine haloacetic acids (the five in HAA5 plus four additional brominated species). It is a monitoring group used to characterize brominated byproducts, not a separately enforced limit.
EPA MCLG Level
N/A mg/L
Maximum level that poses minimal health risk based on the latest science
Health Effects
Reported for monitoring rather than regulated on its own; the haloacetic acids it includes are associated with an increased cancer risk in long-term studies.
Common Sources
- Byproduct of disinfecting drinking water with chlorine
- Formed when chlorine reacts with natural organic matter such as decaying leaves, runoff, and algae
- Elevated when the source water contains naturally occurring bromide
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EPA MCLG Level
The EPA MCLG represents the maximum level that poses minimal health risk based on the latest scientific research. It's often more protective than federal legal limits.
Contaminant Type
HAA9 is classified as a Disinfection Byproducts contaminant.
Related Disinfection Byproducts Contaminants
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Tap Score
Haloacetic Acids (HAA9) Test
$275
Tests for disinfection byproducts formed when chlorine reacts with organic matter in water treatment.
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