Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, Adelaide, SA, 5095, Australia.
Environ Sci Pollut Res Int. 2015 Jun;22(12):8902-10. doi: 10.1007/s11356-013-1782-y. Epub 2013 May 22.
Aqueous film-forming foams (AFFF) are used to extinguish hydrocarbon fuel fires. Certain AFFF products such as 3M Lightwater contain perfluorooctane sulfonate (PFOS) as the active ingredient which is highly persistent in the environment and is thus globally prevalent. With thousands of tons of soils potentially contaminated with PFOS stockpiled at a number of sites in Australia, the lack of reliable information on bioavailability of this recalcitrant contaminant constrains the application of a risk-based strategy for managing such soils. In this study, the PFOS release pattern from soils collected from the contaminated sites of fire training areas and its bioaccumulation potential in earthworm were investigated. The study was conducted at two temperatures (25 and 37 °C) and 60 % of the maximum water-holding capacity of soils. The greatest release into water was found to occur from the soil having the highest PFOS concentration, 16.17 μg g(-1) (Tindal FTA064), thereby demonstrating the role of contaminant loading on release behaviour. The release could also be related to the soil physico-chemical properties. The maximum amount of PFOS was desorbed from the soil with the lowest clay and organic matter content. Bioaccumulation of PFOS in earthworms (Eisensia fetida) as expressed by the bioaccumulation factor (BAF) was found to be highest from soil with the lowest PFOS concentration (RBD soil). The range of BAF found in our study was 1.23 (spiked Tindal SS01 soil) to 13.9 (field contaminated RBD soil). Our study suggests that PFOS could indeed pose a potential risk to ecological safety of soil if present even at concentrations as low as 0.8 μg g(-1) since the highest bioaccumulation factor was found to be from such a soil (field contaminated RBD).
水成膜泡沫灭火剂（AFFF）用于扑灭碳氢化合物燃料火灾。某些 AFFF 产品，如 3M Lightwater，含有全氟辛烷磺酸（PFOS）作为活性成分，它在环境中高度持久，因此在全球范围内普遍存在。由于澳大利亚的许多地点都储存了数千吨可能受到 PFOS 污染的土壤，而关于这种难降解污染物生物有效性的可靠信息缺乏，这限制了基于风险的管理策略在管理这些土壤中的应用。在这项研究中，研究了从火灾训练区污染地点采集的土壤中 PFOS 的释放模式及其在蚯蚓中的生物累积潜力。该研究在两个温度（25 和 37°C）和土壤最大持水能力的 60%下进行。结果发现，PFOS 浓度最高的土壤（16.17μg g(-1)，Tindal FTA064）释放到水中的量最大，从而证明了污染物负荷对释放行为的作用。释放也可能与土壤物理化学性质有关。从粘土和有机质含量最低的土壤中解吸了最多的 PFOS。用生物积累因子（BAF）表示，在蚯蚓（Eisensia fetida）中 PFOS 的生物累积量最高，从 PFOS 浓度最低的土壤（RBD 土壤）中发现。在我们的研究中，BAF 的范围从 1.23（添加的 Tindal SS01 土壤）到 13.9（现场污染的 RBD 土壤）。我们的研究表明，即使 PFOS 的浓度低至 0.8μg g(-1)，如果存在，它确实可能对土壤的生态安全构成潜在风险，因为最高的生物积累因子来自这种土壤（现场污染的 RBD）。
