The arsenic geochemical data and microbial data from sediments in Hama cold seep

Arsenic is a globally significant toxic metalloid and accumulation in seafloor cold seeps, yet its biogeochemical mechanisms remain enigmatic. Through a combination of geochemical and metagenomic analyses, we demonstrate that anaerobic oxidation of methane and the enhanced 'metal particle shuttle effect' synergistically established cold seeps as significant arsenic sink. Notably, we identify key microbial taxa, particularly <i>Desulfobacterota</i>, play a central role in mediating the coupled processes of sulfate reduction, arsenate reduction, and AOM, thereby facilitating arsenic immobilization. Quantitatively, we preliminarily estimate that cold seeps may sequester 4.53-6.14 × 10⁶ kg of arsenic annually, a flux comparable to hydrothermal inputs. Our findings suggest that methane-driven arsenic sequestration in cold seeps may influence global arsenic cycling, particularly during large-scale methane release events.