Occurrence and human health risks of twenty-eight common antibiotics in wild freshwater products from the Xiangjiang River and comparison with the farmed samples from local markets.

The occurrence of 28 common antibiotics in wild and farmed aquatic products from different species was comprehensively investigated in the present study. The results showed that a larger number of antibiotics could be detected quantitatively in wild samples, while the farmed samples had higher concentrations. Twenty, 17, and 14 target compounds were found in the muscles of wild molluscs, wild fish and farmed fish with total concentrations of 2.02-16.4 ng g-1, 0.51-11.9 ng g-1, and <LOD - 144 ng g-1, respectively. Quinolones could be frequently detected in all investigated samples with higher concentrations, while sulphonamides were only detected more frequently in wild molluscs. For wild samples, sulfamethoxazole, sulphamethazine, clarithromycin, and ciprofloxacin are the main antibiotics that were detected in molluscs and fish with different residues. However, there was almost no significant residue difference among different wild fish. Compared with other studies in China or overseas, antibiotic residues in the investigated fish were almost always at a relative low level. Monte Carlo simulation showed that the farmed fish posed higher health risks than the wild fish, while the proportion of the consumers with chronic toxic risk (HI) of farmed fish higher than 0.05 (a distinct risk) was only 1.15 %.