Formation potential of emerging disinfection by-products during ozonation and chlorination of sewage effluents

A Kozari; A Paloglou; D Voutsa

doi:10.1016/j.scitotenv.2019.134449

Formation potential of emerging disinfection by-products during ozonation and chlorination of sewage effluents

Sci Total Environ. 2020 Jan 15:700:134449. doi: 10.1016/j.scitotenv.2019.134449. Epub 2019 Oct 4.

Authors

A Kozari¹, A Paloglou¹, D Voutsa²

Affiliations

¹ Environmental Pollution Control Laboratory, Department of Chemistry, Aristotle University, 541 24 Thessaloniki, Greece.
² Environmental Pollution Control Laboratory, Department of Chemistry, Aristotle University, 541 24 Thessaloniki, Greece. Electronic address: dvoutsa@chem.auth.gr.

PMID: 31639540
DOI: 10.1016/j.scitotenv.2019.134449

Abstract

This study investigates the formation potential of emerging DBPs (haloacetonitriles, halonitromethanes and halopropanones) during ozonation and ozonation/hydrogen peroxide treatment and subsequent chlorination of sewage effluent under various experimental conditions. Estimation of possible risk due to DBPs by calculation of cytotoxicity and genotoxicity was attempted. The studied DBPs showed different formation behavior during chlorination, with maximum yields within 0.5-48 h. Maximum cytotoxicity and genotoxicity was observed after 4 h of chlorination with dibromoacetonitrile being the major contributor. Ozonation and O₃/H₂O₂ treatment resulted in increase of trichloronitromethane followed by a decline at higher doses, and reduction of haloacetonitriles. High ozone doses reduced cytotoxicity and genotoxicity of treated effluents. The presence of bromide shifted to bromo-DBPs formation and enhanced both cytotoxicity and genotoxicity. Particulate fraction in effluents significantly contributed to the formation of DBPs and consequently to the their toxicity.

Keywords: Chlorine; Disinfection by-products; Organic matter; Ozone; Toxicity; Wastewater effluent.