The toxicokinetic of arsenic in the edible and non-edible tissues of freshwater shellfish

Abstract

Although the chemical speciation and distribution characteristics of arsenic in freshwater shellfish have been adequately studied, little is known about the differences in arsenic speciation and bioaccumulation in the edible and non-edible tissues. In this study, we collected Parafossarulus eximius from the Xiang River, which is heavily polluted by mining activities in China. The levels of arsenic species in the shellfish specimens were determined using HPLC-ICP-MS. The average concentration of total arsenic (tAs) in the muscle of dried shellfish was 9.934 ± 7.173 mg ⋅ kg −1 . As(V) and arsenobetaine were the dominant chemical species in the collected samples. Correlations analysis showed that As concentration in sediments directly affects the As concentration in shellfish, especially the non-edible part. A significant correlation between As(III) and As(V) in the edible and the non-edible parts was observed, suggesting a mutual transformation between the two species. Further results from the correlation analysis indicated that when the intake of inorganic arsenic (iAs) by shellfish was high, the biological transformation process from iAs to AsB reached a saturation. The chronic health risk for consumers from P. eximius was not observed. Whereas, continuous consumption would pose considerably carcinogenic risk. • Shellfish from the Xiang River was heavily polluted by mining activities. • As(V) and AsB were the dominant chemical species. • As concentration in sediments directly affects the As concentration in shellfish. • The biological transformation of iAs to AsB has a threshold value. • Continuous consumption of P. eximius would pose considerably to local consumers.