Nitrate in vegetables and fruits consumed in Sicily (Italy) by potentiometry and health risk assessment

In this study, nitrate concentration of 81 fruit and vegetable samples consumed in several cities of Sicily region (Italy) were evaluated. After determining the concentration of nitrate, non-carcinogenic risk assessment in two consumers age groups (children and adults) were carried. The mean concentration of NO3 - in products consumed in Italy was 613 mg Kg-1. The concentration ranged from 23 to 4804 mg Kg-1, the highest one was related to a rocket sample which, however, is lower than the legal limits. Although the matrix considered is much more complex than the aqueous ones, the results obtained by us show that the optimized method for the potentiometric determination of nitrates, using an ion-selective electrode, is accurate, precise and selective. All possible interfering substances, in particular chlorides, were eliminated by adding a silver sulphate solution to the suspension obtained from the sample treatment.