Freeze-induced acceleration of iodide oxidation and consequent iodination of dissolved organic matter to form organoiodine compounds.

Autor: Gong X; School of Resources and Environment, Yangtze University, Wuhan 430100, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China., He M; School of Resources and Environment, Yangtze University, Wuhan 430100, China., Hao Z; School of Resources and Environment, Yangtze University, Wuhan 430100, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: znhao@rcees.ac.cn., Zhao R; Qilu University of Technology (Shandong Academy of Sciences), Shandong Analysis and Test Center, Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province, Jinan 250014, China., Liu J; Institute of Environment and Health, Jianghan University, Wuhan 430056, China. Electronic address: jfliu@rcees.ac.cn.
Jazyk: angličtina
Zdroj: Journal of environmental sciences (China) [J Environ Sci (China)] 2024 Oct; Vol. 144, pp. 67-75. Date of Electronic Publication: 2023 Dec 28.
DOI: 10.1016/j.jes.2023.12.026
Abstrakt: Freeze-induced acceleration of I - oxidation and the consequent iodination of dissolved organic matter (DOM) contribute to the formation of organoiodine compounds (OICs) in cold regions. The formed OICs may be a potentially important source of risk and are very closely with the environment and human health. Herein, we investigated the acceleration effects of the freeze process on I - oxidation and the formation of OICs. In comparison to reactive iodine species (RIS) formed in aqueous solutions, I - oxidation and RIS formation were greatly enhanced in frozen solution and were affected by pH, and the content of I - and O 2 . Freeze-thaw process further promoted I - oxidation and the concentration of RIS reached 45.7 µmol/L after 6 freeze-thaw cycles. The consequent products of DOM iodination were greatly promoted in terms of both concentration and number. The total content of OICs ranged from 0.02 to 2.83 µmol/L under various conditions. About 183-1197 OICs were detected by Fourier transform ion cyclotron resonance mass spectrometry, and more than 96.2% contained one or two iodine atoms. Most OICs had aromatic structures and were formed via substitution and addition reactions. Our findings reveal an important formation pathway for OICs and shed light on the biogeochemical cycling of iodine in the natural aquatic environment.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024. Published by Elsevier B.V.)
Databáze: MEDLINE
Externí odkaz: