摘要
      本研究调查了地表水中抗生素和抗生素抗性基因（ARGs）的地理空间分布及其与人类活动的关系。2020年7月至10月，在双城都市区（明尼苏达州）的39个地点测量了抗生素（水和沉积物）和ARGs（沉积物）的浓度，这些地点经历了与人类活动相关的梯度影响。对于水样，检测到的抗生素数量和某些抗生素（如磺胺类药物）的浓度与城市化指标（如城市百分比、人口密度、废水排放点数量；ρ=0.32–0.46，p=0.003–0.04）呈正相关，与未开发土地指标（如森林；ρ=−0.34至−0.62，p=<0.00001–0.04）呈负相关。沉积物中的抗生素表现出与相应水样不同的地理空间分布，并且与人为因素无关。ARGs的相对丰度与人为因素无关，但几种ARGs（如blaoxa、mexB和sul2）与沉积物的有机物含量呈负相关（ρ=−0.38至–0.44，p=0.01–0.04）。发现各种ARGs和intI1的相对丰度之间存在强相关性（ρ≥0.67，p<0.05），突出了它们在（亚）城市地表水中的共存。这些结果确定了有希望预测抗生素地理空间分布的人为/环境因素，以及监测地表水中ARGs的有用基因标记。
Abstract
This study investigated geospatial distributions of antibiotics and antibiotic resistance genes (ARGs) in surface waters and their associations with anthropogenic activities. During July–October 2020, the concentrations of antibiotics (water and sediment) and ARGs (sediment) were measured at 39 sites in the Twin-Cities metropolitan area (Minnesota) that experience a gradient of impacts related to human activities. For water samples, the number of antibiotics detected and the concentrations of certain antibiotics (e.g., sulfonamides) positively correlated with urbanization indicators (e.g., urban percentage, population density, number of wastewater discharge points; ρ = 0.32–0.46, p = 0.003–0.04) and negatively correlated with undeveloped land indicators (e.g., forest; ρ = −0.34 to −0.62, p = <0.00001–0.04). Antibiotics in sediments exhibited geospatial distribution different from that in corresponding water samples and exhibited no associations with anthropogenic factors. Relative abundances of ARGs were not associated with anthropogenic factors, but several ARGs (e.g., blaoxa, mexB, and sul2) were inversely related to the organic content of sediments (ρ = −0.38 to –0.44, p = 0.01–0.04). Strong correlations were found among relative abundances of various ARGs and intI1 (ρ ≥ 0.67, p < 0.05), highlighting their co-occurrence in (sub)urban surface waters. These results identified promising anthropogenic/environmental factors for predicting antibiotic geospatial distributions and useful gene markers to monitor ARGs in surface waters.

https://pubs.acs.org/doi/full/10.1021/acsestwater.2c00447