Formation of emerging disinfection byproducts from agricultural biomass-derived DOM: Overlooked health risk source. (1st February 2023)

• Record Type: Journal Article
• Authors: Wang, Ruigang; Zhou, Jian; Qu, Guangzhou; Wang, Tiecheng; Jia, Hanzhong; Zhu, Lingyan
• Is Part Of: Water research. Volume 229(2023)
• Publication Date: 2023-02-01
• Subjects: Dissolved organic matter -- Disinfection byproducts -- FT-ICR/MS -- Biochar -- Agricultural biomass; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2022.119482
• Languages: English
• ISSNs: 0043-1354

Abstract

Highlights: Compositions of carbon-derived dissolved organic matter derived from straw were analyzed. Emerging DBPs from different carbon-derived dissolved organic matter were identified. Incineration generated more aromatics, but pyrolysis produced more lignins. H/C of DBP precursors from incineration was 0.2–1.5, and that of pyrolysis was 0.6–2.0. H/Cwa and cytotoxicity negatively related; N/Cwa and genotoxicity positively related. Abstract: Carbon-derived dissolved organic matter (CDOM) are inevitably released to surface water during returning agricultural biomass carbon to farmland, which are potential precursors of disinfection byproducts (DBPs). In this study, CDOM was extracted from aerobic incineration ("OX") and anoxic pyrolysis ("PY") of three kinds of straw (wheat, corn, and rice), and the emerging DBPs from them were deciphered. The CDOM with molecular weight < 1 kDa in the OX and PY groups accounted for 53–87%, and it was higher in the PY group. A total 1343–2107 of CHO and 641–1761 of CHNO formulas were detected in the CDOM derived from the OX group, among which 74%-83% contained aromatic structures rich in oxygen containing groups. 1919–3289 of CHO and 785–1954 of CHNO formulas were observed in the PY group, and 77%-86% of them were lignins/CRAM-like compounds. Surprisingly, 765–2158 and 895–1648 of emerging DBPs were identified in the OX and PY groups, and the proportions of N-DBPs were 20.3–54.8% and 2.8–4.8%, respectively. Based on HOCl addition and Cl substitution mechanisms, the H/C ratios of the DBP precursors in the OX and PY groups were in the range of 0.2–1.5 and 0.6–2.0, respectively. The DBPs derived from the OX group exhibited higher cytotoxicity and genotoxicity due to the higher aromaticity and more N-DBPs. Thus, returning agricultural biomass carbon, particularly that produced by direct combustion, to farmland brought potential threat to drinking water safety. Graphical abstract: Image, graphical abstract