Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, United States; Environmental Science and Policy Program, Michigan State University, East Lansing, MI, 48824, United States; Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, United States.
Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, United States.
Chemosphere. 2021 Jan;262:127677. doi: 10.1016/j.chemosphere.2020.127677. Epub 2020 Jul 15.
Plant uptake of antibiotics raises serious food safety concerns. Measurements and predictions of antibiotic uptake by plants are often based on root concentration factors (RCF) determined using antibiotic concentrations in bulk soil (RCF) rather than in rhizosphere soil (RCF) where root uptake actually occurs. This study investigated the fate and transport of nine antibiotics in the continuum of bulk soil, rhizosphere soil, roots and shoots of lettuce (Lactuca sativa) under soil-surface irrigation. Antibiotic concentrations in the lettuce shoots remained unchanged during 25-35 days after seedling transplantation. Compared with the RCF values, the RCF values were significantly greater for ciprofloxacin, lincomycin, oxytetracycline, sulfamethoxazole, and tetracycline (p < 0.05), similar for trimethoprim and tylosin, but significantly lower for monensin (p < 0.05). Ciprofloxacin, trimethoprim, and tylosin had the lowest translocation factors (TF) ranging between 0.03 and 0.05, suggesting their limited upward transport to the lettuce shoots. Oxytetracycline, monensin, and sulfamethoxazole had intermediate TF values of 0.36-0.64, whereas lincomycin had the highest TF value of 1.46. This study showed significant differences between RCF and RCF values, suggesting the need to reassess the utility of RCF in predicting the antibiotic root uptake in diverse soil-plant systems.
植物对抗生素的吸收引起了严重的食品安全问题。抗生素在植物体内的吸收的测量和预测通常基于使用大量土壤中的抗生素浓度（RCF）而不是在根际土壤中（RCF）确定的根浓度系数（RCF），尽管根吸收实际上发生在根际土壤中。本研究调查了在土壤表面灌溉条件下，九种抗生素在大量土壤、根际土壤、生菜（生菜）根系和地上部之间的连续体中的归趋和迁移。幼苗移植后 25-35 天，生菜地上部的抗生素浓度保持不变。与 RCF 值相比，环丙沙星、林可霉素、土霉素、磺胺甲恶唑和四环素的 RCF 值显着更高（p<0.05），甲氧苄啶和泰乐菌素的 RCF 值相似，但莫能菌素的 RCF 值显着更低（p<0.05）。环丙沙星、甲氧苄啶和泰乐菌素的转运因子（TF）最低，在 0.03 到 0.05 之间，表明它们向上运移到生菜地上部的能力有限。土霉素、莫能菌素和磺胺甲恶唑的 TF 值介于 0.36 到 0.64 之间，而林可霉素的 TF 值最高，为 1.46。本研究表明 RCF 和 RCF 值之间存在显着差异，这表明需要重新评估 RCF 在预测不同土壤-植物系统中抗生素根吸收的有用性。
