[Distribution Characteristics of Sulfonamide Antibiotic Resistance Genes in a Drinking Water Source in East China].

Antibiotic resistance genes (ARGs) in drinking water sources have attracted widespread attention due to the threat they pose to water security and human health. This study mainly focused on the distribution of sulfonamide ARGs () and one integrase gene () in water and sediment using qualitative and fluorescent quantitative PCR, based on previous work on the characteristics of 13 kinds of sulfonamides in a drinking water source in East China. Results showed that the three target genes were all detected in water and sediment. The gene was the sulfonamide ARG with highest concentration, with 1.5×10-6.4×10 copies·mL in source water and maximum concentration of 1.6×10 copies·g in sediment. Concentration of was 0.6-2.2, 0.5-1.9 order of magnitudes higher than and genes, respectively. There was no significant difference between the absolute concentrations of , and in inflow and outflow. However, in the case of sediment, absolute abundances of , and in outflow were higher than those in inflow. The maximum concentration of was detected in outflow in summer (6.4×10 copies·mL). The concentration of was higher in winter compared to other seasons. There was a positive correlation between and 13 sulfonamides (=0.69, <0.05), and the relative concentration of and amount of sulfamethoxazole were significantly positively related (=0.79, <0.01). There were also positive correlations between the relative concentrations of and (:0.80 and 0.73, <0.05), respectively, suggesting that played an important role in horizontal gene transfer of sulfonamide ARGs in this drinking water source. This study provides basic data for monitoring pollution of ARGs, as well as a basis for controlling ARG pollution in the drinking water environment and making management decisions.