Illinois Sustainable Technology Center, University of Illinois at Urbana-Champaign, 1 Hazelwood Drive, Champaign, IL 61820, United States.
Illinois Sustainable Technology Center, University of Illinois at Urbana-Champaign, 1 Hazelwood Drive, Champaign, IL 61820, United States.
Sci Total Environ. 2023 Oct 15;895:165080. doi: 10.1016/j.scitotenv.2023.165080. Epub 2023 Jun 24.
Biosolids and sewage effluent application to agricultural fields is becoming a win-win practice as both an economical waste management strategy and a source of nutrients and organic matter for plant growth. However, these organic wastes contain a variety of trace chemicals of environmental concern such as pharmaceuticals and personal care products (PPCPs), which may pose a risk to agricultural fields and ecosystems. This work aims to investigate the sorption of sitagliptin on four agricultural soils, evaluate the effects of biosolids and sewage effluent application, and elucidate the main sorption mechanism of the pharmaceutical on soils. The sorption study revealed that the sorption capacities of sitagliptin on different soils were positively related to the contents of soil organic matter and negatively associated with soil pH values. The application of biosolids and sewage effluent decreased the sorption capacity of sitagliptin, which may be attributed to the loading of dissolved organic matter derived from organic wastes. The Freundlich isotherm model demonstrated that the addition of biosolids from 0 to 100 % (W/W) consistently decreased the sorption affinity (K) of sitagliptin from 1.69 × 10 to 3.82 × 10 mg L kg. Sewage application at 0, 10, 50, and 100 % (V/V) also reduced the K values from 1.69 × 10 to 9.17 × 10 mg L kg. Attenuated Total Reflection (ATR)-Infrared (IR) spectroscopy analyses suggested that electrostatic interactions between carbonyl and amino groups of sitagliptin and the negatively charged soil surface are the main sorption mechanisms. In a co-solute system, the sorption affinity of sitagliptin on the soil decreased with increasing metformin concentrations, suggesting that competitive sorption may reduce the sorption capacity of individual contaminants in soil systems containing multiple PPCPs.
生物固体和污水废水施用于农田是一种双赢的做法，因为它既是一种经济的废物管理策略，也是植物生长的营养物质和有机物质的来源。然而，这些有机废物中含有多种环境关注的痕量化学物质，如药品和个人护理产品（PPCPs），这可能对农田和生态系统构成风险。本工作旨在研究西他列汀在四种农业土壤上的吸附，评估生物固体和污水废水施用量的影响，并阐明该药品在土壤上的主要吸附机制。吸附研究表明，西他列汀在不同土壤上的吸附能力与土壤有机质含量呈正相关，与土壤 pH 值呈负相关。生物固体和污水废水的施用量降低了西他列汀的吸附能力，这可能归因于有机废物中溶解有机质的负载。Freundlich 等温线模型表明，生物固体从 0 到 100%（W/W）的添加一致降低了西他列汀的吸附亲和力（K）从 1.69×10 到 3.82×10 mg L kg。污水以 0、10、50 和 100%（V/V）的添加量也降低了 K 值从 1.69×10 到 9.17×10 mg L kg。衰减全反射（ATR）-红外（IR）光谱分析表明，西他列汀的羰基和氨基与带负电荷的土壤表面之间的静电相互作用是主要的吸附机制。在共溶质体系中，随着二甲双胍浓度的增加，西他列汀在土壤上的吸附亲和力降低，这表明在含有多种 PPCPs 的土壤体系中，竞争吸附可能会降低单个污染物的吸附容量。
