Key Laboratory of Geographic Information Science of Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai, China.
Key Laboratory of Geographic Information Science of Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai, China; Institute of Eco-Chongming (IEC), East China Normal University, Shanghai, China.
Environ Pollut. 2021 Feb 15;271:116361. doi: 10.1016/j.envpol.2020.116361. Epub 2020 Dec 23.
Vegetable consumption is a potential toxin exposure pathway for humans. Studies have recognized that vegetables can uptake organic contaminants via roots and translocate pollutants to their aerial parts. However, the aerial parts might also directly uptake polycyclic aromatic hydrocarbons (PAHs) from contaminated soils. This has not been extensively studied. The aim of this study was to explore the uptake and translocation of PAHs in contaminated soil-air-vegetable systems. Sixteen individual PAHs in contaminated soils, vegetable roots, and leaves were identified using GC-MS. The results showed that the average PAH concentrations both in roots and leaves from the reference soil, the moderately contaminated soil, and the heavily polluted soil increased as expected. PAHs with log K < 5 accumulated more easily in roots and leaves. Using a Pearson correlation analysis, isomer ratios, and a principal component analysis (PCA), it was found that the contaminated soil not only caused PAH accumulation in roots, but also increased the PAH concentration in leaves. Quantitatively, the absorption of PAHs in roots in the moderately contaminated soil (70.3 ng m) was approximately twice that of the reference soil (40.8 ng m). The PAHs absorbed by vegetable roots in the heavily polluted soil (74.7 ng m) was only slightly higher than that of the moderately polluted soil. In addition, the PAH dose volatilized into the air from the reference soil, the moderately contaminated soil, and the heavily polluted soil also showed an increasing trend. The incremental lifetime cancer risk (ILCR) indicated that adult females had a higher cancer risk via vegetable consumption than other groups. Although vegetable consumption had a slight effect on cancer risk for some groups in the present study, the cancer risk of PAHs caused by eating vegetables grown in heavily contaminated soil still requires attention.
蔬菜摄入是人类潜在的毒素暴露途径。研究已经认识到，蔬菜可以通过根部吸收有机污染物，并将污染物转移到其地上部分。然而，地上部分也可能直接从受污染的土壤中吸收多环芳烃（PAHs）。这方面的研究还不是很广泛。本研究旨在探索受污染土壤-空气-蔬菜系统中 PAHs 的吸收和迁移。使用 GC-MS 鉴定了受污染土壤、蔬菜根系和叶片中的 16 种单个 PAHs。结果表明，参考土壤、中度污染土壤和重度污染土壤中根系和叶片中的平均 PAH 浓度均按预期增加。log K<5 的 PAHs更容易在根部和叶片中积累。通过皮尔逊相关分析、同系物比值和主成分分析（PCA），发现受污染的土壤不仅导致根部 PAH 积累，而且增加了叶片中的 PAH 浓度。定量分析表明，中度污染土壤中蔬菜根系对 PAHs 的吸收（70.3ng·m）约为参考土壤的两倍（40.8ng·m）。重度污染土壤中蔬菜根系吸收的 PAHs（74.7ng·m）略高于中度污染土壤。此外，参考土壤、中度污染土壤和重度污染土壤中 PAH 挥发到空气中的剂量也呈上升趋势。增量终生癌症风险（ILCR）表明，成年女性通过食用蔬菜摄入 PAHs 的癌症风险高于其他群体。尽管在本研究中，蔬菜消费对某些群体的癌症风险有轻微影响，但仍需关注食用重度污染土壤种植的蔬菜所带来的 PAHs 致癌风险。
