Determinazione quali-quantitativa di tre antibiotici in Mytilus galloprovincialis raccolti nelle coste della Sardegna

The health of humans, animals, and the environment are strictly interconnected. We can be infected by the same agents and treated with the same drugs, affecting each other's health. Antibiotics are used for therapeutic and prophylactic purposes in both human and veterinary medicine and still in some countries as growth- promoting agents in livestock farms and aquaculture. They can accumulate in environmental matrices and the food chain, causing adverse effects in humans and animals, including the development of antibiotic resistance. Moreover, antibiotics are considered among the most worrying 'emerging contaminants', both because their cumulative toxic effects on aquatic organisms are not well known, and because their continued presence in the environment leads to the development of antibiotic- resistant bacteria. Also, they can act at low concentrations by modifying the natural microbial diversity of aquatic ecosystems. For several years, the Pharmacology and Toxicology research group of the Department of Veterinary Medicine in Sassari has been working on the validation of new analytical methods for the identification and quantification of emerging contaminants in biological matrices. The aim of this thesis is to develop an analytical method for the simultaneous quantitative determination of antibiotics in a biological matrix. Specifically, the Mytilus galloprovincialis was used, a mussel species present and cultivated in Sardinia, and used as a “sentinel organism” inenvironmental monitoring programs. The analytical method was validated for the simultaneous determination of erythromycin, azithromycin and sulfamethoxazole using liquid chromatography interfaced with the tandem mass spectrometer (LC-MS/MS). None of the three investigated antibiotics were found in the samples analyzed at concentrations above the method's limits of determination (LODs). The results therefore demonstrate the healthiness of the mussels about food safety, and a negligible pollution factor for the antibiotics chosen in the studied areas.