Characteristics And Risk Assessment Of Seven Typical Antibiotic Residues In Fish Pond From Lingui District,Guilin

Antibiotics play a positive role in the prevention and treatment of fish diseases.However,irregular and unscientific use of antibiotics has caused a large amount of residues in the aquatic environment,which has become one of the new pollutants in the environment.Seven typical antibiotics including three Sulfonamides（（Sulfadiazine,SDZ）,（Sulfamethazine,SM2）,（Sulfamethoxazole,SMX））and four Quinolones（（Ciprofloxacin,CIP）,（Enrofloxacin,ENR）,（Norfloxacin,NOR）,（Ofloxacin,OFL））in water,sediment and fish of fish pond from Lingui District,Guilin,Guangxi Zhuang Autonomous Region were tested in this study,aimint to clarify the antibiotic residues in the water,sediment and fish of the aquaculture environment in the region,and to evaluate the risks of the ecological environment and human health.It could provide basic data for assessing the ecological risk of antibiotic residues in cultured water bodies in Lingui District,Guilin,and it is of great theoretical significance for ensuring the health of urban residents and the safety of the regional ecological environment,and improving the monitoring and management system for fish drug residues.The results are as follows:1.The seven typical antibiotics in fish pond water were detected,and the detection frequencies of SDZ,SMX,CIP and ENR were 100%.The total concentrations of seven typical antibiotics were as follows:ENR>SMX>SDZ>CIP>NOR>SM2>OFL.The total concentration of quinolone groups and sulfonamide groups in fish pond water from Lingui District were 3531.54 ng/L and 2775.57 ng/L,respectively.The Pearson correlation analysis indicated that the concentrations of seven typical antibiotics were related to total nitrogen（TN）,total phosphorus（TP）,total organic carbon（TOC）,chemical oxygen demand(COD_Cr).2.The average antibiotics contents of the two group antibiotics in fish pond sediment from Lingui District shows the following rules:OFL>SMX>SM2>SDZ>NOR>ENR>CIP,with the 100%detection frequencies of SM2,SMX,ENR and NOR.In addition,the contents of antibiotics were related to TN,TP and organic matter in the sediment.3.A total of 66 fish individuals were collected in fish pond from Lingui District,which were identified to be 11 species,belonging to 11 genera,4 families and 2 orders.The fitting curve of Cyprinus carpio length and weight relationship is a power function relationship,which belongs to Isometric growth.The content of NOR in fish ranged from 0.83 to 2.22μg/kg,with the 100%detection frequencies in all fish.SM2 and OFLin fish were as high as 19.69μg/kg and 4.80μg/kg,respectively.The antibioticscontents in Cyprinus carpio,Pelteobagrus fulvidraco and Cyprinus carpio speculariswere higher than other fish.Some antibiotics were detected in the feed which the content ranged from 0～1351.03μg/kg.4.The risk assessment of seven typical antibiotics in fish pond from Lingui District were analyzed via the Risk Quotient（RQ）and the Health Quotient（HQ）.The results showed that SMX,CIP and ENR pose high risk（RQ>1）to the relevant sensitive microorganisms,while SM2 pose low risk（RQ<0.1）in fish pond water.SMX and NOR in the sediment pose high risk（RQ>1）to the relevant sensitive microorganisms at all sampling sites,with CIP and OFL at high risk（RQ>1）at part of sampling sites.The human health risk quotient（HQ）of each antibiotic in the fish is less than 1.It can be considered that the antibiotic exposure has subtle impact on the dietary safety of the human,and the fish can be eaten with guarantee.