Arsenic (As) pollution has become a serious environmental problem in China, South Asia, Southeast Asia and other places. Arsenate [As(V)] mainly exists in marine environment, which has high toxicity, teratogenicity, carcinogenesis and other hazards. Arsenic is bioaccumulated and passed along the food chain, resulting in risks to seafood safety and marine ecology and potential health threats to consumers.
Salinity plays a major role in As migration, and it is the key controlling factor. As species in seawater and sediment significantly influences As migration. Arsenobetaine (AsB) is more easily transferred and absorbed along the food chain than inorganic As during the transfer process of different As forms, and the transfer efficiency along the food chain of AsB is 4-9 times higher than that of inorganic As. The transport and transformation rules of As between different tissues of marine fish were revealed, the synthesis of AsB in the intestines and AsB absorbed from food slowly pass through the intestinal membrane and reach different tissues in marine fish through the bloodstream circulation. It was first reported that bhmt, mat2aa and gstt1a were the key genes involved in AsB synthesis in marine medaka, which provided the key evidence for AsB synthesis. Osmotic regulation is a key factor driving the synthesis of AsB in marine fish. Low salinity promotes amino acid synthesis to maintain osmotic balance, whereas high salinity facilitates AsB synthesis of osmotic regulation. In high-salinity (30‰) environments, marine fish exhibit enhanced capacity to convert inorganic As into AsB. It was observed that GB, GSH, SAM, and AsC participated in the metabolic pathways of methionine and glutathione, leading to increased synthesis of AsB. In high- salinity (30‰) environments, betaine plays an important role in AsB synthesis. Therefore, As migration and transformation behavior in marine ecosystems provided important theoretical support for the seafood safety, marine ecology, and human health risks of As.

 

Arsenic,migration,transformation,marine fish