TZW: DVGW-Technologiezentrum Wasser (German Water Centre), Karlsruher Str. 84, 76139 Karlsruhe, Germany.
Landwirtschaftliches Technologiezentrum Augustenberg (LTZ), Neßlerstr. 25, 76227 Karlsruhe, Germany.
Sci Total Environ. 2021 Apr 20;766:142640. doi: 10.1016/j.scitotenv.2020.142640. Epub 2020 Oct 3.
A main source of perfluoroalkyl and polyfluoroalkyl substances (PFASs) residues in agricultural plants is their uptake from contaminated soil. Bioaccumulation factors (BAFs) can be an important tool to derive recommendations for cultivation or handling of crops prior consumption. This review compiles >4500 soil-to-plant BAFs for 45 PFASs from 24 studies involving 27 genera of agricultural crops. Grasses (Poaceae) provided most BAFs with the highest number of values for perfluorooctanoic acid and perfluorooctane sulfonic acid. Influencing factors on PFAS transfer like compound-specific properties (hydrophobicity, chain length, functional group, etc.), plant species, compartments, and other boundary conditions are critically discussed. Throughout the literature, BAFs were higher for vegetative plant compartments than for reproductive and storage organs. Decreasing BAFs per additional perfluorinated carbon were clearly apparent for aboveground parts (up to 1.16 in grains) but not always for roots (partly down to zero). Combining all BAFs per single perfluoroalkyl carboxylic acid (C4-C14) and sulfonic acid (C4-C10), median log BAFs decreased by -0.25(±0.029) and -0.24(±0.013) per fluorinated carbon, respectively. For the first time, the plant uptake of ultra-short-chain (≤ C3) perfluoroalkyl acids (PFAAs) was reviewed and showed a ubiquitous occurrence of trifluoroacetic acid in plants independent from the presence of other PFAAs. Based on identified knowledge gaps, it is suggested to focus on the uptake of precursors to PFAAs, PFAAs ≤C3, and additional emerging PFASs such as GenX or fluorinated ethers in future research. Studies regarding the uptake of PFASs by sugar cane, which accounts for about one fifth of the global crop production, are completely lacking and are also recommended. Furthermore, aqueous soil leachates should be tested as an alternative to the solvent extraction of soils as a base for BAF calculations.
农业植物中全氟烷基和多氟烷基物质（PFAS）残留的一个主要来源是它们从受污染土壤中的吸收。生物积累因子（BAF）可以成为在食用前对农作物种植或处理提出建议的重要工具。本综述汇总了 24 项研究中涉及 27 种农业作物的 45 种 PFAS 从 4500 多份土壤到植物的 BAF。禾本科（Poaceae）为全氟辛酸和全氟辛烷磺酸提供了最多的 BAF 值和数量。本文还批判性地讨论了影响 PFAS 转移的因素，如化合物的特性（疏水性、链长、官能团等）、植物种类、植物组织以及其他边界条件等。在整个文献中，植物营养器官的 BAF 高于生殖和贮藏器官。对于地上部分，每增加一个全氟碳原子，BAF 就会明显降低（在谷物中高达 1.16），但对于根部并非总是如此（部分降低至零）。对于每一种单一的全氟烷基羧酸（C4-C14）和全氟烷基磺酸（C4-C10），结合所有 BAF，中值 log BAF 分别减少了-0.25（±0.029）和-0.24（±0.013）个全氟碳原子。本文首次综述了超短链（≤C3）全氟烷基酸（PFAAs）在植物中的吸收情况，结果表明，三氟乙酸在植物中的存在是普遍的，而与其他 PFAAs 的存在无关。基于确定的知识空白，建议在未来的研究中重点关注 PFAAs 的前体、PFAAs≤C3 以及新兴的 PFAS 如 GenX 或氟醚的吸收。关于甘蔗（占全球作物产量的五分之一左右）对 PFAS 吸收的研究完全缺乏，也建议开展此类研究。此外，还应测试土壤浸提液作为土壤溶剂萃取的替代物，作为 BAF 计算的基础。
