Department of Civil and Environmental Engineering, University of Maryland, College Park, MD 20742, USA.
Environ Pollut. 2012 Jan;160(1):103-8. doi: 10.1016/j.envpol.2011.09.020. Epub 2011 Oct 14.
This study investigates the persistence of Triclosan (TCS), and its degradation product, Methyltriclosan (MeTCS), after land application of biosolids to an experimental agricultural plot under both till and no till. Surface soil samples (n = 40) were collected several times over a three years period and sieved to remove biosolids. Concentration of TCS in the soil gradually increased with maximum levels of 63.7 ± 14.1 ng g(-1) dry wt., far below the predicted maximum concentration of 307.5 ng g(-1) dry wt. TCS disappearance corresponded with MeTCS appearance, suggesting in situ formation. Our results suggest that soil incorporation and degradation processes are taking place simultaneously and that TCS background levels are achieved within two years. TCS half-life (t(0.5)) was determined as 104 d and MeTCS t(0.5), which was more persistent than TCS, was estimated at 443 d.
本研究调查了三氯生（TCS）及其降解产物甲基三氯生（MeTCS）在土地施用生物固体后，在翻耕和免耕两种情况下在实验性农田中的持久性。在三年内多次采集了表面土壤样本（n = 40）并进行筛分以去除生物固体。土壤中 TCS 的浓度逐渐增加，最高水平达到 63.7 ± 14.1 ng g(-1)干重，远低于预测的 307.5 ng g(-1)干重的最大浓度。TCS 的消失与 MeTCS 的出现相对应，表明其是原位形成的。我们的研究结果表明，土壤的掺入和降解过程同时发生，并且 TCS 的背景水平在两年内达到。TCS 的半衰期（t(0.5)）为 104 d，而比 TCS 更持久的 MeTCS 的半衰期（t(0.5)）估计为 443 d。
