Institute of Urban Water Management, Technische Universität Dresden, 01062, Dresden, Germany.
Institute of Groundwater and Earth Sciences, Jinan University, 510632, Guangzhou, China.
Environ Pollut. 2018 Aug;239:638-647. doi: 10.1016/j.envpol.2018.04.075. Epub 2018 Apr 27.
In this study, 14 antibiotics and one metabolite were determined in sewages and size-dependent sewer sediments at three sampling sites in the city of Dresden, Germany. Adsorption and desorption experiments were conducted with fractionated sediments. All antibiotics and the metabolite investigated were determined in the sewages; 9 of 14 antibiotics and the metabolite were adsorbed to sewer sediments. The adsorbed antibiotic loads in ng of antibiotic per g of sediment correlated with antibiotic concentrations in ng of antibiotic per litre of sewage. The size fractions <63 μm, 63-100 μm and 100-200 μm had significantly higher loads of adsorbed antibiotics than bigger size fractions. In general, the adsorbed load decreased with an increasing size fraction, but size fractions >200 μm had similar levels of adsorbed antibiotic loads. An antibiotic-specific adsorption coefficient, normalized to organic content, was calculated: four antibiotics exceeded 10.0 L g, three antibiotics fell below 1.0 L g and all residual antibiotics and the metabolite were in the range of 1.0-10.0 L g. The adsorbed antibiotic load and the organic matter increased with time, generally. The mineral composition had a minor effect on the adsorption coefficients. Desorption dynamics of five antibiotics and the metabolite were quantified. Regardless of the size fraction, the predominant part of the equilibrium antibiotic concentration was desorbed after 10 min. The calculated desorption distribution coefficient indicated adsorption as irreversible at the pH investigated (7.5 ± 0.5).
本研究在德国德累斯顿市的三个采样点，测定了污水和不同粒径的下水道沉积物中的 14 种抗生素和一种代谢物。采用分级沉积物进行了吸附和解吸实验。所有研究的抗生素和代谢物均在污水中被检测到；14 种抗生素中有 9 种和代谢物被吸附到下水道沉积物中。吸附在沉积物中的抗生素负荷（每克沉积物中抗生素的纳克数）与污水中抗生素浓度（每升污水中抗生素的纳克数）相关。<63 μm、63-100 μm 和 100-200 μm 的粒径分数的吸附抗生素负荷明显高于较大粒径分数。一般来说，随着粒径分数的增加，吸附负荷会降低，但粒径分数>200 μm 的吸附抗生素负荷水平相似。计算了抗生素特异性吸附系数，归一化到有机含量：四种抗生素超过 10.0 L/g，三种抗生素低于 1.0 L/g，所有剩余抗生素和代谢物均在 1.0-10.0 L/g 范围内。吸附抗生素负荷和有机物随时间普遍增加。矿物质组成对吸附系数的影响较小。定量研究了五种抗生素和代谢物的解吸动力学。无论粒径分数如何，在 10 分钟后，平衡抗生素浓度的主要部分被解吸。计算出的解吸分布系数表明，在所研究的 pH 值（7.5±0.5）下，吸附是不可逆的。
