Formation of iodinated trihalomethanes during chlorination of amino acid in waters

Chemosphere. 2019 Feb:217:355-363. doi: 10.1016/j.chemosphere.2018.10.190. Epub 2018 Oct 30.

Abstract

Chlorination is essential to provide safe drinking water. However, this process leads to the formation of disinfection byproducts (DBPs). In this study, tryptophan (Trp) has been selected as a precursor to conduct the chlorine disinfection. Moreover, the factors that affect the formation of trihalomethanes (THMs) and iodinated trihalomethanes (I-THMs) are investigated. The formation pathway of Trp chlorination is proposed based on the intermediate products identified. According to the experimental results, the formation of THMs and I-THMs during Trp chlorination fitted a new first-order kinetic model. The dosage of chlorine, temperature, pH and the ratio of bromide and iodide had major influence on the formation of THMs and I-THMs during chlorination. In addition, the inhibition of luminescent bacteria Vibrio fischeri in the water sample increased during Trp chlorination.

Keywords: Amino acid; Chlorination; Iodinated trihalomethanes; Trihalomethanes; Tryptophan.

MeSH terms

  • Aliivibrio fischeri / drug effects
  • Amino Acids / chemistry*
  • Bromides / chemistry
  • Chlorine / chemistry
  • Disinfection / methods
  • Drinking Water / chemistry
  • Halogenation*
  • Iodides
  • Trihalomethanes / chemistry*
  • Trihalomethanes / pharmacology
  • Water Pollutants, Chemical / analysis
  • Water Purification / methods*

Substances

  • Amino Acids
  • Bromides
  • Drinking Water
  • Iodides
  • Trihalomethanes
  • Water Pollutants, Chemical
  • Chlorine