Freeze-induced acceleration of iodide oxidation and consequent iodination of dissolved organic matter to form organoiodine compounds.
J Environ Sci (China)
; 144: 67-75, 2024 Oct.
Article
in En
| MEDLINE
| ID: mdl-38802239
ABSTRACT
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 O2. 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.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Oxidation-Reduction
/
Water Pollutants, Chemical
/
Freezing
/
Iodides
Language:
En
Journal:
J Environ Sci (China)
Journal subject:
SAUDE AMBIENTAL
Year:
2024
Document type:
Article
Affiliation country:
Country of publication: