ObjectiveTo understand the distribution of enrofloxacin (ENR) residues in freshwater fish, to evaluate the dietary exposure risk to ENR for consumers through the consumption of different freshwater fish in Shanghai, and to provide a reference for controlling antibiotic residues in freshwater fish. MethodsGrass carp, Wuchang bream, pond loach, and Asian swamp eels were purchased from the markets in Shanghai. After being fed with ENR, the fish were divided into 42 batches according to their species and weight, and thereafter ENR residues in the muscles and skin of the fish were measured. In addition, a total of 44 batches of Wuchang bream, pond loach, Asian swamp eels were purchased from the markets, and the ENR residues in the muscles with or without the fish skin were measured, and the exposure risk was evaluated. ResultsThe average residues of ENR in skin of the freshwater fish after being fed with drugs in the 42 groups were higher than those in muscles (M=659.38 μg·kg^-1, M=460.83 μg·kg^-1; z=-2.212, P=0.027). The over-standard rates of ENR residues in the muscles with or without skin 44 batches of freshwater fish of sold in Shanghai were 36.36% and 29.55%, respectively. The median exposure, P₉₅ exposure, and maximum exposure to ENR through the consumption of the muscles with the skin for adults and children in Shanghai were higher than those through the consumption of muscles without the skin. For children, the margin of safety (MOS) for the max exposure to ENR by consuming the muscles with the skin was more than 1, while the MOS was less than 1 in all other cases for both children and adults. ConclusionThe ENR residues in the skin of freshwater fish are generally higher than those in the muscles. The risk of ENR residues in freshwater fish sold in Shanghai is within a controllable range. However, there might be a certain risk of acute exposure to ENR for children by consuming muscles with the skin of freshwater fish.

ObjectiveTo understand the concentration of heavy metal cadmium and cadmium in portunus and mantis shrimp， and to timely identify food safety problems and potential hazards. MethodsPortunus and mantis shrimp samples from different provinces were collected and categorized based on different regions and locations， and some samples were made from tissue parts. Graphite furnace atomic absorption spectrometry was used to detect cadmium items， the cadmium exposure of portunus and mantis shrimp was evaluated simultaneously ResultsThe detection rate of cadmium in 124 batches of portunus sold in Shanghai was 100% （124/124）， the detection rate of cadmium in 63 batches of mantis shrimp sold in the market was also 100% （63/63）. The cadmium content varied in different tissue parts， and the cadmium enrichment in hepatopancreas was the highest in the edible parts of portunus and mantis shrimp. The average detection value， 50th percentile value， 95th percentile value of cadmium in the hepatopancreas of portunus accounted for 52.64%， 49.28% and 98.65% of the PTMI， respectively. The average detection value， 50th percentile value and 95th percentile value of cadmium in the hepatopancreas of mantis shrimp accounted for 30.76%， 32.04% and 46.16% of the PTMI， respectively. ConclusionThe average residual levels of heavy metal cadmium in portunus and mantis shrimp are within the safe range.