A sensitive LC–ESI-MS/MS method was developed for the determination of 165 pesticides in 50 citrus fruit samples collected in Sicily. Moreover, an evaluation of pesticides levels in the citrus layers (peel, albedo, and pulp) was carried out. The method presented acceptable trueness, precision, and linearity with LOQ of 5 μg/kg. The results obtained showed a high frequency of fungicides class pesticides in all the citrus samples examined (>95%) with the highest concentrations in the peel (4468 µg/Kg). A significant difference of concentrations was found between the layers of the citrus fruits analysed (p < 0.05). In particular, the peel and albedo present higher pesticides significantly higher than the pulp. Our findings confirming the widespread use of these substances in citrus cultivation and suggesting the importance of pesticides analysis in all the citrus fruit layers separately, considering the different interactions between the physicochemical characteristics of the matrices and the pesticides. Graphical Abstract

The aim of this study was to investigate mercury accumulation in some species, caught in Mediterranean Sea, in the period between May and December 2015, and to compare it to the presence of Anisakis parasites. The samples were examined by direct mercury analyzer (DMA-80) for their Hg levels. The metal concentration was compared to the presence or the absence of Anisakis parasites. Significant differences in Hg concentration in analysed samples were observed. The low-infested fishes contained 1–6 larvae of parasites whereas the high-infested one had 7–83 larvae.

A total of 205 bluefin and yellowfin tuna samples were examined for mercury detection in order to verify possible differences and have a detailed risk assessment of the two tuna species. The results showed significant higher mercury concentration in muscle tissue of bluefin tuna respect yellowfin tuna (p < 0.001) with mean concentration of 0.84 mg/kg and maximum value of 1.94 mg/kg. These differences can be due the different biological and ecological aspects of the two tuna species and to different oceanographic aspects between Atlantic Ocean and Mediterranean sea. The results obtained in this study suggest an advisable containment of the sources of pollution and further studies on the closed-loop farming of bluefin tuna, in order to ensure the product safety.