Veterinary drug residues determination in raw milk in Croatia

A total of 1259 raw milk samples were examined over a three-year period for various antibiotics chloramphenicol, penicillins, cephalosporines, tetracyclines, sulfonamides, beta-lactams, quinolones, aminoglycosides and macrolides. Microbiological and immunoassay methods used for determination of these antibiotics were validated according to the guidelines laid down by European Commission Decision 2002/657/EC. Microbiological screening detected 36 positive samples and in only one sample presence of residues was confirmed. Also, immunoassay determination found one positive sample on tetracycline residues. In total, 37 positive samples were determined, which was equal to a frequency of 0.69% of the total number of targeted analyses. The HPLC-DAD method confirmed the presence of residues above the maximum residue limits (MRLs) in two samples with concentrations of 12 μg kg−1 for penicillin G and 19 μg kg−1 for amoxicillin, and 1671 μg kg−1 for tetracycline. Calculated estimated daily intakes (EDIs) for antibiotics presented showed lower exposure levels than the fixed values of acceptable daily intakes (ADIs). These suggested that raw milk in Croatia contain very low levels of veterinary drugs so that toxicological risk with regard to consuming of milk could not be considered as a public health problem.