Arsenic speciation in fish from Baltic Sea close to chemical munitions dumpsites

Chemical weapons that were dumped in seas and oceans after World War II, including the Baltic Sea, are sources of pollution of marine areas. Sunken containers can corrode, unseal, and numerous compounds pass into the environment, including toxic forms of arsenic, which are then taken up by marine animals. This study aims to quantify concentration of total arsenic, inorganic arsenic (III + V), and organic compounds arsenobetaine, monomethylarsonic acid, dimethylarsinic acid in the muscle tissues of cod, herring, sprat, and flounder and the associated risk to consumer health. Sprat muscle (0.636 mg kg^-1) had the highest content of total arsenic, significantly less was noted in the muscles of herring (0.460 mg kg^-1) and flounder (0.588 mg kg^-1), and the least was in cod (0.390 mg kg^-1). Toxic inorganic arsenic compounds were present in the fish tested at levels below 0.02 mgkg^-1 and constituted from 3.45 to 5.75% of total arsenic. Arsenobetaine dominated among organic forms, and concentrations of it, like total arsenic, varied depending on the fish species. Consumer health risk was determined with the estimated daily intake, the target hazard quotient, and the carcinogenic risk. Estimated daily intake values for inorganic arsenic in herring, cod, sprat, and flounder were below the reference dose at 0.51 × 10^-5 mg kg^-1 b. w. day. The target hazard quotient factor of 0.0017 indicated there was no threat. Carcinogenic risk values were within the permissible range of 10^-6 to 10^-4. Current data indicate that inorganic arsenic compounds pose no risk to the health of consumers of Baltic fishes.