Dept. of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Dept. of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
J Hazard Mater. 2016 Jan 25;302:72-81. doi: 10.1016/j.jhazmat.2015.09.035. Epub 2015 Sep 25.
A screening-level risk assessment of biosolids-borne PPCPs in agricultural scenarios was developed in this work. While several of these compounds are efficiently removed in sewage treatment plants (STPs), others are recalcitrant to degradation and can be found in sludge at significant levels. As the rate of biosolids reuse for fertilising and/or amendment purposes is increasing, it is necessary to evaluate the fate in soil and possible biotransfer of this type of pollutants in the long-term. The study includes six compounds that were selected considering data availability, presence in sludge and persistence. Due to the scarce data still present in literature, a probabilistic assessment to address uncertainty was developed. A 95th percentile of the hazard index (HI) exceeding 1 was obtained, with main contributions of triclosan and carbamazepine. Although these estimates were obtained under a worst-case approach, and that they can vary depending on scenario characteristics, they change the least-concern classification associated to the presence of PPCPs in biosolids. A sensitivity analysis indicates the high influence of application rate and sludge concentration level on the results. Thus, the importance of developing new strategies of removal in advanced STPs and the establishment of a specific biosolids reuse regulation including this type of compounds acquires an added significance.
本研究开展了农业场景中生物固体携带的 PPCPs 的筛选水平风险评估。尽管这些化合物中的一些在污水处理厂（STP）中被有效去除，但其他化合物则难以降解，并且可以在污泥中以显著水平存在。随着生物固体再利用为施肥和/或改良目的的速度增加，有必要评估其在土壤中的命运以及这种类型污染物在长期内可能的生物转移。该研究包括考虑数据可用性、污泥存在和持久性而选择的六种化合物。由于文献中仍存在稀缺数据，因此开发了概率评估以解决不确定性。危害指数（HI）的 95 百分位超过 1，其中三氯生和卡马西平的贡献最大。尽管这些估计值是在最坏情况下获得的，并且可能因情景特征而异，但它们改变了与生物固体中 PPCPs 存在相关的最不关注分类。敏感性分析表明，应用率和污泥浓度水平对结果的影响很大。因此，开发先进的 STP 中去除这些化合物的新策略以及建立包括此类化合物的特定生物固体再利用法规变得尤为重要。
