Determination of Inorganic Arsenic in Grape Products Using HPLC-ICP-MS

The inorganic arsenic (i-As) in grape products, in particular juice, wine and raisins, collected from the Japanese market was investigated. The concentrations of total As in nine grape concentrated juices ranged from 3 to 20 ng g^-1, and more than 80% of the As was inorganic according to the results of speciation by HPLC-ICP-MS. Among them, four samples contained more than 10 ng g^-1 of i-As, although 10 ng g^-1 of i-As is the limit for apple juice recommended by the U.S. Food and Drug Administration. Moreover, more than 10 ng g^-1 of i-As was found in some of the wine and raisin samples, with the total As concentrations ranging from 17 to 37 ng g^-1. When fresh grapes were analyzed, As was mainly concentrated in the pericarp and a small amount was found in the fruit, although no As was observed in the branches and the juice. When grapes, including the pericarp, are processed, the As concentration in the products may increase during production processes such as drying, concentration, and ripening.