A global survey on total arsenic concentrations in sharks

Several shark species worldwide present high total arsenic (As) concentrations in muscle tissue, although to what extent has not yet been systematized. This study assessed total As concentrations in different shark species, as these animals comprise a significant fishery resource worldwide and are paramount for ecosystem equilibrium. A scientometric assessment retrieved 21 articles published between 1993 and 2023 reporting total As concentrations in muscle tissue of 27 shark species belonging to 16 different genera landed around the globe. Total As concentrations ranged from 0.14 to 152.20 mg kg^-1 wet weight and are not explained by mean length variability (23 to 297 cm). Toxic inorganic As contents usually range from 0.6 to 5%, in sharks, and organic, non-toxic, concentrations vary from 85 to 98% of total As contents, due to biologically-driven chemical speciation changes. Because of this, speciation assessments are paramount to adequately assess human health risks due to shark meat consumption.