Abstract:Heavy metal is a typical persistent pollutant, which can enter organisms through various ways such as respiration, drinking water and food chain transmission, and can be circulated among plants, animals, microorganisms and humans. At the same time, with the transfer of heavy metals and the transformation of valence or form, heavy metals with different valence or form may have significant toxicity differences and produce typical toxic effects on organisms. In food production, raw materials, processing, and human digestion and metabolism may cause changes in the valence, morphology, and total amount of heavy metals, thereby significantly affecting their toxicity. At present, in the risk assessment of heavy metals in food, the risks caused by changes in their morphology or valence are ignored. This paper reviews the risks caused by the transfer and transformation of heavy metals in the food industry chain, which is of great significance for the scientific assessment of the toxicity of heavy metals entering the human body through the food chain, especially the heterogeneous hazards of heavy metal in the process of transfer and speciation or valence transformation, in order to provide theoretical guidance for the scientific assessment of heavy metal pollution in food.