NILU - Norwegian Institute for Air Research, Hjalmar Johansens gate 14, Tromso, Norway.
Chemosphere. 2021 Aug;276:130044. doi: 10.1016/j.chemosphere.2021.130044. Epub 2021 Feb 24.
There is a growing concern over a suspected presense of unknown perfluoroaliphatic substances (PFAS) in consumer goods and in the environment. Such unknown substances, possibly with high molecular weight, might be precursors of hazardous or controlled known PFAS. Recent studies confirmed that total organic fluorine (TOF) content often can not be explained by the measured target PFAS. One of the suspected classes of such unknowns are polymers with fluorotelomer alcohol (FTOH) residues in a side chain. In this report we suggest hydrolysis of precursors, as a complementary method to account for the unknown PFAS. It was shown here that hydrolysis allows to preserve structural information on the perlfuorinated parts of the precursors, which can be an advantage for the purpose of accurate risk assessment or source identification. A convenient procedure for hydrolysis with 4% sodium hydroxide in water-methanol mixture (1:9) at 60 °C for 16 h was shown to convert model substances - FTOH acrylate, methacrylate and isobutyrate esters as well as FTOH phenylcarbamate to free FTOHs. Analysis of extracts of textile samples with preliminary hydrolysis and without it showed up to 1300-fold higher level of "hidden" FTOHs.
人们越来越关注消费品和环境中存在的未知全氟脂肪族物质（PFAS）。这些未知物质，可能具有高分子量，可能是危险或受管制的已知 PFAS 的前体。最近的研究证实，总有机氟（TOF）含量通常不能用测量的目标 PFAS 来解释。其中一种可疑的未知物质类别是在侧链中具有氟调聚物醇（FTOH）残基的聚合物。在本报告中，我们建议使用水解作为补充方法来解释未知的 PFAS。结果表明，水解可以保留前体中全氟化部分的结构信息，这对于准确的风险评估或来源识别可能是一个优势。在 60°C 下用 4%氢氧化钠在水-甲醇混合物（1:9）中水解 16 小时的简便方法，可将 FTOH 丙烯酸酯、甲基丙烯酸酯和异丁酸酯以及 FTOH 苯甲酰胺等模型物质转化为游离 FTOH。对经初步水解和未经水解的纺织品样品提取物的分析显示，“隐藏”的 FTOH 水平高达 1300 倍。
