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[Detection and assessment of antibiotic and sex hormone residues in Eriocheir sinensis sold in markets in Shanghai].

OBJECTIVE
To understand the antibiotic and sex hormone residue level in the Eriocheir sinensis sold in markets in Shanghai.


METHODS
Fifty six mitten crabs were collected through convenient sampling in Xuhui and Changning districts in Shanghai in 2014. The residues of 13 antibiotics (4 quinolones, 3 sulfonamides, 2 tetracyclines, 2 amphenicols, 1 macrolides, and trimethoprim) and 7 sex hormones (4 endogenous sex hormones and 3 synthetic sex hormones) were detected by the isotope dilution method based on ultra-performance liquid chromatography coupled to quadrupole/time-of-flight mass spectrometry in visceral organs and muscles of crabs.


RESULTS
A total of 7 antibiotics were detected in visceral organs or muscles of crabs, including 3 quinolones (ciprofloxacin, norfloxacin, and enrofloxacin), 3 sulfonamides (sulfamethazine, sulfadiazine, and sulfamethoxazole) and trimethoprim. In visceral organs, the overall antibiotic detection rate was 32.1%, the maximum sum of mass concentration was 23.8 µg/kg, and the 75th percentile was 1.45 µg/kg. In muscles, the overall antibiotic detection rate was 39.3%, the maximum sum of mass concentration was 40.5 µg/kg, and the 75th percentile was 1.75 µg/kg. No sex hormones were detected in both visceral organs and muscles.


CONCLUSION
The antibiotic and sex hormone residue level in the Eriocheir sinensis sold in markets in Shanghai did not exceed the national standard, indicating that no risk was posed to human health.