Eldridge Morgan, LaFond Jessica, Anderson Todd, Guelfo Jennifer, Jackson W Andrew
Department of Environmental Toxicology, Texas Tech University, Lubbock, TX, 79416, USA.
Department of Civil, Environmental, and Construction Engineering, Texas Tech University, Lubbock, TX, 79409, USA.
Environ Monit Assess. 2025 May 27;197(6):686. doi: 10.1007/s10661-025-14138-8.
Quantifying per- and polyfluoroalkyl substances (PFAS) in soil is a crucial part of site evaluations. Several methods are currently used in commercial and academic labs to evaluate PFAS-affected soils, with differences in extraction solvent, extraction method, cleanup procedure, and instrumental analysis among laboratories. This study aims to compare the accuracy and efficiency of a legacy in-house soil extraction method for PFAS with EPA Method 1633 for sample extraction and analysis using liquid chromatography tandem mass spectrometry (LC-MS/MS). An aqueous film-forming foam (AFFF)-impacted field soil (Soil A), a "clean soil" (Ottawa sand), and a certified reference soil were subjected to both extraction methods. Subsamples of these soils were also submitted to an accredited commercial lab. The commercial lab analyzed samples in accordance with EPA Method 1633 both for extraction and analysis. For comparison, our lab extracted the samples with both EPA Method 1633 and the in-house legacy soil extraction method, followed by a large-volume injection (LVI) adaptation of EPA Method 1633 instrumental analysis method. The EPA Method 1633 followed by LVI analysis quantified slightly more compounds without quality control flags than the legacy extraction method followed by LVI analysis for Soil A and the certified reference soil. Both in-house extractions had 76% of reportable compound concentrations within ± 15% relative standard deviation. The commercial small-volume injection results returned the least number of quality control flags, but quantified fewer compounds at low concentrations. Considering the time and cost of EPA Method 1633 and commercial analysis, this study supports the suitability of the legacy soil extraction method with LVI LC-MS/MS analysis for in-house soil analysis with comparable results to EPA Method 1633 as well as commercial analysis.
量化土壤中的全氟和多氟烷基物质（PFAS）是场地评估的关键部分。目前，商业实验室和学术实验室使用多种方法来评估受PFAS影响的土壤，各实验室在萃取溶剂、萃取方法、净化程序和仪器分析方面存在差异。本研究旨在比较一种传统的内部土壤PFAS萃取方法与美国环境保护局（EPA）方法1633在使用液相色谱串联质谱（LC-MS/MS）进行样品萃取和分析时的准确性和效率。对一种受水成膜泡沫（AFFF）影响的现场土壤（土壤A）、一种“清洁土壤”（渥太华砂）和一种有证参考土壤进行了这两种萃取方法的测试。这些土壤的子样本也被送到一家经认可的商业实验室。该商业实验室按照EPA方法1633进行萃取和分析。为了进行比较，我们实验室用EPA方法1633和传统的内部土壤萃取方法对样品进行萃取，然后采用EPA方法1633仪器分析方法的大体积进样（LVI）改进方法。对于土壤A和有证参考土壤，采用EPA方法1633然后进行LVI分析定量的未带质量控制标记的化合物比采用传统萃取方法然后进行LVI分析的略多。两种内部萃取方法的可报告化合物浓度有76%在相对标准偏差±15%以内。商业小体积进样结果的质量控制标记最少，但低浓度下定量的化合物较少。考虑到EPA方法1633和商业分析的时间和成本因素，本研究支持传统土壤萃取方法结合LVI LC-MS/MS分析用于内部土壤分析的适用性，其结果与EPA方法以及商业分析相当。
