Helmholtz-Zentrum Geesthacht, Institute of Coastal Research, 21502, Geesthacht, Germany; Universität Hamburg, Institute of Inorganic and Applied Chemistry, 20146, Hamburg, Germany.
Helmholtz-Zentrum Geesthacht, Institute of Coastal Research, 21502, Geesthacht, Germany.
Environ Pollut. 2020 Dec;267:115567. doi: 10.1016/j.envpol.2020.115567. Epub 2020 Aug 31.
This study aimed at comparing source-specific fingerprints of per- and polyfluoroalkyl substances (PFASs) in river water from China and Germany, selected as countries with different histories of PFAS production. Samples were collected from up- and downstream of seven suspected point sources in autumn 2018. Amongst the 29 analyzed legacy and emerging PFASs, 24 were detected, with a sum ranging from 2.7 ng/L (Alz River) to 420,000 ng/L (Xiaoqing River). While mass flow estimates for the Xiaoqing River and Yangtze River (mean: 20 and 43 t/y, respectively) indicated ongoing high emissions of the legacy compound PFOA in China, its ether-based replacements HFPO-DA and DONA showed the highest contribution downstream of a German fluoropolymer manufacturing site (50% and 40% of ΣPFASs measured, respectively). In river water impacted by manufacturing sites for pharmaceutical and pesticide intermediates, the short-chain compound PFBS was the most prevalent substance in both countries. The German Ruhr River, receiving discharges from the electroplating industry, was characterized by the PFOS replacement 6:2 FTSA. Isomer profiling revealed a higher proportion of branched isomers in the Chinese Xi River and Xiaoqing River than in other rivers. This points to different synthesis routes and underlines the importance of differentiating between linear and branched isomers in risks assessments. Upon oxidative conversion in the total oxidizable precursor (TOP) assay, the increase of the short-chain compound PFBA was higher in German samples than in Chinese samples (88 ± 30% versus 12 ± 14%), suggesting the presence of a higher proportion of unknown precursors to PFBA in the German environment. Amongst the ether-based replacements, DONA and 6:2 Cl-PFESA were fully or partially degraded to non-targeted oxidation products, whereas HFPO-DA showed no degradation. This indicates that the inclusion of ether-based PFASs and their oxidation products in the TOP assay can help in capturing a larger amount of the unknown PFAS fraction.
本研究旨在比较来自中国和德国的河流水中特定来源的全氟和多氟烷基物质 (PFASs) 的指纹图谱，这两个国家分别具有不同的 PFAS 生产历史。2018 年秋季，从 7 个疑似点源的上下游采集了样品。在所分析的 29 种传统和新兴 PFAS 中，有 24 种被检出，总浓度范围为 2.7ng/L（阿尔兹河）至 420,000ng/L（小清河）。虽然小清河和扬子江的质量流量估算（平均值分别为 20 和 43 吨/年）表明中国仍在大量排放传统化合物 PFOA，但它的醚基替代品 HFPO-DA 和 DONA 在德国氟聚合物制造工厂的下游贡献最高（分别占所测ΣPFAS 的 50%和 40%）。在受制药和农药中间体制造工厂影响的河流中，短链化合物 PFBS 是两个国家最普遍的物质。接收电镀工业排放物的德国鲁尔河的特征是 PFOS 替代品 6:2 FTSA。异构体分析表明，中国的习河和小清河的支链异构体比例高于其他河流。这表明存在不同的合成途径，并强调了在风险评估中区分线性和支链异构体的重要性。在总可氧化前体 (TOP) 测定中进行氧化转化时，德国样品中短链化合物 PFBA 的增加率高于中国样品（88±30%比 12±14%），这表明德国环境中未知 PFBA 前体的比例较高。在醚基替代品中，DONA 和 6:2 Cl-PFESA 完全或部分降解为非靶向氧化产物，而 HFPO-DA 没有降解。这表明将醚基 PFASs 及其氧化产物纳入 TOP 测定可以帮助捕获更多未知的 PFAS 部分。
