Department of Chemical, Biochemical and Environmental Engineering, University of Maryland Baltimore County , 1000 Hilltop Circle, Baltimore, Maryland 21250, United States.
Environ Sci Technol. 2016 Apr 5;50(7):3444-52. doi: 10.1021/acs.est.5b06164. Epub 2016 Mar 23.
The bioavailability of polycyclic aromatic hydrocarbons (PAHs) in soils can be influenced by the source material they are emitted within, the properties of the receiving soil, weathering processes, and the concentration of PAHs. In this study 30 contaminated soils were constructed with common PAH sources (fuel oil, soot, coal tar based skeet particles) and direct spike with a solvent added to different types and contents of soil organic matter and minerals to achieve PAH concentrations spanning 4 orders of magnitude. Source material had the greatest impact on PAH partitioning. Soils containing skeet generally exhibited the highest KD values, followed by soot, fuel oil, and solvent spiked soils. Among all soil compositions, the presence of 2% charcoal had the largest enhancement of KD. Partitioning behavior could not be predicted by an organic carbon and black carbon partitioning model. Including independently measured partitioning behavior of the soil components and PAH sources allowed better prediction but still suffered from issues of interaction (oil sorption in peat) and highly nonlinear partitioning with depletion (for skeet). Dermal absorption of PAHs measured using pig skin was directly related to the freely dissolved aqueous concentration in soil and not the total concentration in the soil. Overall, we show that PAH source materials have a dominating influence on partitioning, highlighting the importance of using native field soils in bioavailability and risk assessments.
多环芳烃（PAHs）在土壤中的生物可利用性可能受到其排放源物质、受纳土壤的性质、风化过程以及 PAHs 浓度的影响。在这项研究中，使用常见的 PAH 源（燃料油、烟尘、煤焦油基弹丸颗粒）构建了 30 个受污染土壤，并通过溶剂直接添加到不同类型和含量的土壤有机质和矿物质中，以实现跨越 4 个数量级的 PAH 浓度。源物质对 PAH 分配的影响最大。一般来说，含有弹丸的土壤表现出最高的 KD 值，其次是烟尘、燃料油和溶剂添加土壤。在所有土壤组成中，2%的木炭存在对 KD 的增强最大。有机碳和黑碳分配模型无法预测分配行为。包括独立测量的土壤成分和 PAH 源的分配行为可以更好地进行预测，但仍然存在相互作用（泥炭中的油吸附）和高度非线性分配与消耗（弹丸）的问题。使用猪皮测量的 PAHs 的皮肤吸收与土壤中自由溶解的水相浓度直接相关，而与土壤中的总浓度无关。总的来说，我们表明 PAH 源物质对分配有主导影响，这突出了在生物有效性和风险评估中使用天然野外土壤的重要性。
