Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China; International Livestock Research Institute, Nairobi, Kenya.
Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China.
Environ Pollut. 2023 Dec 1;338:122696. doi: 10.1016/j.envpol.2023.122696. Epub 2023 Oct 5.
Wastewater irrigation may introduce antibiotic residues in the soil-plant systems. This study aimed to investigate the uptake of tetracyclines by spinach and collard greens and assess associated ecological and human health risks. Synthetic wastewater spiked with 1 ppm and 10 ppm of oxytetracycline, doxycycline, and tetracycline was used to grow vegetables in a greenhouse pot experiment. The uptake and accumulation of the tetracyclines were low and residual concentrations in the soil were negligible. All the tetracyclines were detected at concentrations ranging from 1.68 to 51.41 μg/g (spinach) and 1.94-30.95 μg/g (collard greens). The accumulation rate was in a dose-response scenario with a bioconcentration factor of 6.34 mL/kg (spinach) and 2.64 mL/kg (collard greens). Oxytetracycline had the highest accumulation in leaves, followed by doxycycline and tetracycline, and the residual concentrations followed the same order. The highest residual concentration was in soils receiving 10 ppm oxytetracycline. Residual concentrations in the soil were lower than accumulated levels and exerted negligible ecological risks. Tetracyclines accumulation in spinach significantly differed between the vegetables demonstrating a subspecies difference in uptake and accumulation. Ecological risk quotient (RQ) and human health risk quotient (HQ) were below thresholds that would exert toxicity and resistance selection impacts. Although RQs and HQs are low (<0.1), this study shows that the vegetables accumulate tetracyclines from irrigation water, posing plausible human health risks to allergic individuals. Similarly, the ecological risks cannot be ignored because the synergistic and antagonistic effects of sublethal concentrations can perturb ecosystem processes.
污水灌溉可能会使土壤-植物系统中引入抗生素残留。本研究旨在研究菠菜和羽衣甘蓝对四环素的吸收，并评估其相关的生态和人类健康风险。采用合成污水对蔬菜进行温室盆栽实验，污水中添加了 1 ppm 和 10 ppm 的土霉素、强力霉素和四环素。四环素的吸收和积累量较低，土壤中的残留浓度可以忽略不计。所有四环素均以 1.68-51.41μg/g（菠菜）和 1.94-30.95μg/g（羽衣甘蓝）的浓度被检测到。积累率与生物浓缩因子呈剂量反应，分别为 6.34 mL/kg（菠菜）和 2.64 mL/kg（羽衣甘蓝）。土霉素在叶片中的积累量最高，其次是强力霉素和四环素，残留浓度也遵循同样的顺序。在接受 10 ppm 土霉素处理的土壤中，残留浓度最高。土壤中的残留浓度低于积累水平，对生态的影响可以忽略不计。在蔬菜中，四环素的积累量存在明显差异，表明在吸收和积累方面存在亚种差异。生态风险商（RQ）和人类健康风险商（HQ）均低于产生毒性和抗性选择影响的阈值。尽管 RQs 和 HQs 较低（<0.1），但本研究表明，蔬菜会从灌溉水中吸收四环素，对过敏个体可能存在潜在的健康风险。同样，生态风险也不容忽视，因为亚致死浓度的协同和拮抗作用会扰乱生态系统过程。
