Unique bioaccumulation and biosynthesis of arsenobetaine in marine fish

Arsenic (As) contamination represents a significant global concern, particularly prevalent in regions such as China, South Asia, and Southeast Asia. Arsenic permeates the food chain, posing potential hazards to ecosystems and human health. Studies have shown that marine fish possess a unique ability to accumulate substantial levels of arsenobetaine (AsB). However, the mechanism underlying the elevated abundance of AsB in marine fish has not been definitively identified. This review examines the significant accumulation of AsB in marine fish, the influence of salinity on AsB concentrations in the aquatic environment, the migration of As through food chains, the biotransport patterns of As in marine fish, the transformation potential of various As forms into AsB, the genes responsible for AsB biosynthesis, and the prediction of AsB accumulation and transformation mechanism in marine fish via machine learning. It provides a comprehensive analysis of established and hypothesized synthetic pathways associated with AsB. By elucidating these insights, this review establishes a foundation for preventing and mitigating the risks posed by As pollution to ecosystems and human health, thereby advancing the field of As ecotoxicology.