To investigate the speciation composition of arsenic and the differences in arsenic bioaccessibility among various edible mushrooms, and to evaluate their impacts on dietary health risk assessment outcomes.

The 18 kinds of common edible mushroom species collected in Guizhou Province were selected as research materials. Arsenic speciation analysis and in vitro physiologically based extraction test were performed.Combined with estimated daily intake, target hazard quotient and target cancer risk models, the transformation pattern of arsenic species during gastrointestinal digestion was quantitatively elucidated, and subsequent health risk assessment was conducted.

The total arsenic concentrations in the tested edible mushrooms ranged from 0.0245 to 0.7458 mg/kg.Only Agaricus blazei exceeded the national limit specified in GB 2762—2022 National food safety standards-Limits of contaminants in food (stipulates 0.5 mg/kg). The proportion of inorganic arsenic to total arsenic varied from 2.83% to 90.04%, with its bioaccessibility ranging between 0.00 and 70.42%, showing significant interspecies differences. After bioaccessibility correction, the concentration of toxic inorganic arsenic decreased to 0–0.1138 mg/kg, meanwhile, the estimated daily intake, target hazard quotient and target cancer risk of inorganic arsenic in digestive fluids were reduced to values closer to the actual human exposure levels.

Arsenic speciation and the bioaccessibility during gastrointestinal digestion exert prominent influences on health risk assessment of arsenic in edible mushrooms.Incorporating both indicators into the risk assessment framework can substantially improve the accuracy of risk evaluation, and provide scientific evidence for the formulation of arsenic pollution prevention and control strategies as well as food safety standards for edible mushrooms.