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Visualizing Methane-Cycling Microbial Dynamics in Coastal Wetlands
Published on: January 31, 2025
A photochemical source of methyl chloride in saline waters
1Department of Oceanography, Dalhousie University, Halifax, NS, Canada. robert.moore@dal.ca
Abstract:
It is shown experimentallythatthe methoxy group in simple lignin-like molecules can be the source of the methyl group in CH3Cl produced by a photochemical reaction in an aqueous solution of chloride. Terrestrially derived colored dissolved organic matter (CDOM) in river water also yields CH3Cl through a photochemical process in a chloride solution. CDOM extracted from subsurface ocean waters showed some ability to enhance photochemical production of CH3Cl while CDOM from surface water showed no effect. Reactions of the kind described in this paper may be contributors to the marine source of methyl chloride and possibly other alkyl halides.
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