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Particles in swimming pool filters--does pH determine the DBP formation?
Kamilla M S Hansen1, Sarah Willach, Hans Mosbæk
1Department of Environmental Engineering, Technical University of Denmark (DTU), Miljoevej, 2800 Kgs. Lyngby, Denmark.
Chemosphere
|January 31, 2012
Summary
Disinfection byproducts (DBPs) like trihalomethanes (THMs) and haloacetic acids (HAAs) formation decreased with lower pH, while haloacetonitriles (HANs) increased. HANs were the primary cause of toxicity in swimming pool particles.
Area of Science:
- Environmental Chemistry
- Water Treatment Science
- Public Health
Background:
- Disinfection byproducts (DBPs) form during water chlorination, posing health risks.
- Swimming pool water contains particles that can contribute to DBP formation.
- Understanding DBP formation and toxicity is crucial for safe recreational water.
Purpose of the Study:
- To investigate the formation of trihalomethanes (THMs), haloacetic acids (HAAs), and haloacetonitriles (HANs) from swimming pool filter particles.
- To assess the toxicity of these DBPs at different pH levels (6.0–8.0).
- To compare DBP formation from particles versus other water matrices.
Main Methods:
- Chlorination of hot tub filter particles under controlled conditions.
- Experiments conducted at varying pH levels and chlorine concentrations.
- Quantification of THM, HAA, and HAN formation.
- Estimation of genotoxicity and cytotoxicity of the formed DBPs.
Main Results:
- THM and HAA formation decreased as pH decreased.
- HAN formation increased as pH decreased.
- DBP formation from particles was relatively higher than from body fluid analogues or filling water.
- Toxicity increased with decreasing pH, with HANs being the main contributors.
Conclusions:
- pH significantly influences the type and amount of DBPs formed from swimming pool particles.
- Lower pH conditions favor the formation of more toxic DBPs, particularly HANs.
- Swimming pool particles are a significant source of DBPs with considerable toxicity.
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