State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China.
State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China.
Chemosphere. 2024 Feb;349:140954. doi: 10.1016/j.chemosphere.2023.140954. Epub 2023 Dec 14.
Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants in the environment, which are teratogenic, carcinogenic, and mutagenic. Co-contamination of PAHs and heavy metal commonly exists in soil. In this study, 20 types of soils with different properties in China were collected and comprehensively characterized. Phenanthrene (Phe) and Cu (II) were selected as representatives of PAHs and heavy metals, respectively. The adsorption-desorption behaviors of Phe under Phe contamination and Cu (II)-Phe co-contamination in 20 types of soils were studied. The adsorption-desorption behaviors of Phe in 20 types of soils varied greatly, and adsorption of Phe in the soils followed both linear partitioning and nonlinear surface adsorption. Soil organic matter (SOM) plays an important role in the adsorption-desorption behavior of Phe. When the concentrations of Phe were >50 μg/L, soft carbon (SC) fraction of SOM not black carbon (BC) contributed more to the adsorption of Phe. Soil dissolved organic matter (DOM), especially fulvic acid and humic acid fractions, contributes to the adsorption of Phe. Under the effect of Cu (II) (60 mg/L in solution), the adsorption capacity of soil for Phe increased, which possibly resulted from lowered pH, the existence of the cation-π bonding and the "bonding bridge" effect. The systematic investigation of adsorption-desorption behaviors of Phe in soils under heavy metal-PAHs co-contamination will provide a scientific basis for the calculation of soil environmental capacity in the future.
多环芳烃(PAHs)是环境中的持久性有机污染物,具有致畸、致癌和致突变性。PAHs 和重金属通常在土壤中共同污染。本研究采集了中国 20 种不同性质的土壤,并进行了综合特征描述。菲(Phe)和 Cu(II)分别选为 PAHs 和重金属的代表物,研究了在 Phe 污染和 Cu(II)-Phe 共污染下,20 种土壤中 Phe 的吸附-解吸行为。20 种土壤中 Phe 的吸附-解吸行为差异较大,Phe 在土壤中的吸附同时遵循线性分配和非线性表面吸附。土壤有机质(SOM)在 Phe 的吸附-解吸行为中起着重要作用。当 Phe 浓度>50μg/L 时,SOM 中的软碳(SC)而非黑碳(BC)对 Phe 的吸附贡献更大。土壤溶解有机质(DOM),特别是富里酸和腐殖酸,有助于 Phe 的吸附。在 Cu(II)(溶液中 60mg/L)的作用下,土壤对 Phe 的吸附能力增加,这可能是由于 pH 值降低、阳离子-π 键的存在和“键桥”效应所致。对重金属-PAHs 共污染下土壤中 Phe 的吸附-解吸行为的系统研究,将为未来计算土壤环境容量提供科学依据。