Arsenic speciation in fish products and seafood as a prerequisite for proper risk assessment

The Boi Cerbus lagoon, facing a mining and industrial site in Sardinia (Italy), is an important fishing area for the local population. Previous studies showed high concentrations of total arsenic (As_tot) in fish, molluscs and crustaceans sampled in the lagoon, and a possible exceeding of the provisional tolerable weekly intake set by the Joint FAO/WHO Expert Committee on Food Additives by some local consumer groups. However, the percentage of inorganic As (As_inorg) should be known for a correct assessment of potential risk, as its toxicity is much higher than that of the organic forms. Eighty samples of 14 different species of fish, molluscs and crustaceans, sampled in the Boi Cerbus lagoon in 3 different seasons (winter, spring and summer), were analysed for As_tot by inductively coupled plasma mass spectrometry (ICP-MS) and As_inorg by high performance liquid chromatography-ICP-MS. All the data obtained from the analysis were statistically processed to evaluate significant differences based on season, taxon and habitat, in preparation for a subsequent risk assessment.