Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China.
College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China.
Sci Total Environ. 2019 Jun 20;670:170-180. doi: 10.1016/j.scitotenv.2019.03.168. Epub 2019 Mar 14.
Urban rivers in some countries have been heavily polluted and the water became black and odor. Nevertheless, only few studies reported the occurrence of antibiotics and their corresponding antibiotic resistant genes (ARGs) in urban rivers with black-odor water with and without remediation. In this study, nine antibiotics (belonging to sulfonamides, tetracyclines, quinolones, and macrolides) and their corresponding ARGs in water and sediments of six urban rivers in Guangzhou, South China were analyzed to investigate their spatial distribution and the influence of water remediation. The concentrations of individual antibiotics varied from ND (not detectable) to 2702 ng/L and ND to 449 μg/kg in surface water and sediments, respectively. Norfloxacin displayed the highest average concentrations, followed by ciprofloxacin. The relative abundance of quinolone-resistance gene qnrA (10 ARGs/16S rRNA) was the highest, followed by tetracyclines-resistance genes tetC (10 ARGs/16S rRNA). The antibiotics and ARGs in sediments from various rivers exhibited distinct spatial distribution with large variation from upstream to downstream. Generally, levels of antibiotics and tetracyclines-resistance genes (tetA, tetC and tetM) in urban rivers with black-odor water (affected by industrial and domestic sewage) were higher than those in remediated urban rivers. Significant positive correlations were observed only between the relative abundances of tetA (or tetC) with the concentrations of some antibiotics (e.g., ciprofloxacin and norfloxacin). TetA was also significantly positively correlated with the concentrations of Ni, Cr, and As in sediments. This study found that urban rivers remediated with dredging might lower antibiotic levels in sediment, but high relative abundance of certain ARGs (e.g., tetB, qnrA) may still exist.
一些国家的城市河流受到了严重污染，水变得又黑又臭。然而，只有少数研究报道了在有和没有修复的黑臭水的城市河流中抗生素及其相应的抗生素抗性基因（ARGs）的存在情况。在这项研究中，分析了中国南方广州的六条城市河流中的水和沉积物中的九种抗生素（属于磺胺类、四环素类、喹诺酮类和大环内酯类）及其相应的 ARGs，以调查它们的空间分布和水修复的影响。个别抗生素的浓度在地表水和沉积物中分别从 ND（未检出）到 2702ng/L 和 ND 到 449μg/kg 不等。诺氟沙星的平均浓度最高，其次是环丙沙星。喹诺酮类抗性基因 qnrA（10 ARGs/16S rRNA）的相对丰度最高，其次是四环素类抗性基因 tetC（10 ARGs/16S rRNA）。不同河流沉积物中的抗生素和 ARGs 表现出明显的空间分布，从上游到下游差异很大。一般来说，受工业和生活污水影响的黑臭水城市河流中的抗生素和四环素类抗性基因（tetA、tetC 和 tetM）水平高于修复后的城市河流。只有在 tetA（或 tetC）的相对丰度与某些抗生素（如环丙沙星和诺氟沙星）的浓度之间观察到显著的正相关。tetA 还与沉积物中 Ni、Cr 和 As 的浓度呈显著正相关。本研究发现，采用疏浚进行修复的城市河流可能会降低沉积物中的抗生素水平，但某些 ARGs（如 tetB、qnrA）的相对丰度仍可能存在。
