Comparison of two extraction methods for the analysis of per- and polyfluorinated chemicals in digested sewage sludge

MOE Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin 300071, China.
Journal of Chromatography A (Impact Factor: 4.17). 07/2010; 1217(31):5026-34. DOI: 10.1016/j.chroma.2010.05.061
Source: PubMed


A rapid and reliable analytical method, based on ion-pair extraction, clean-up on Envicarb cartridge and detection by liquid chromatography-tandem mass spectrometry (LC-MS/MS), was developed for determination of 17 per- and polyfluorinated chemicals (PFCs) in digested sewage sludge. Envicarb cartridge and six labeled internal standards were selected for the elimination/reduction and correction of matrix effects, respectively. As a result, the matrix effect for perfluorooctane sulfonamides (FOSAs) and perfluorocarboxylic acids (PFCAs) with carbon chain length from C6 to C14 was lowered to a range of -14% to +28%. However, the matrix effect for other analytes was still great mainly due to the absence of appropriate internal standard. Mean recoveries of the target analytes based on matrix spikes, at different spike levels (10-300ng/g), ranged from 70% to 169%. Relative standard deviations (RSDs) were in the range of 2-20% at different spike levels. The limit of quantification (LOQ) ranged between 0.6 and 30ng/g. The method was successfully applied to several sewage sludge samples from wastewater treatment plants nearby Zürich, Switzerland. In addition, by comparing the accuracy and precision of ion-pair extraction method and methanol extraction method, we further demonstrated that the ion-pair extraction method can be used for the analysis of PFCs in sludge samples. To our knowledge, this is the first study to extract the PFCs in sewage sludge with ion-pair method and to find unsaturated fluorotelomer carboxylic acids (FTUCAs) in sewage sludge.

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Available from: Kurunthachalam Kannan
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    • "As can be observed in Table 1, the LODs and LOQs obtained were below 0.4 and 1.4 ng/mL, respectively. LODs and LOQs were similar to the values reported in the literature [14] [38] but it should be highlighted that up to 24 target analytes were considered in the present work. "
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    • "14.6 and 176 ng/g, respectively, in Horgen WWTP with 20,560 inhabitant equivalents (11.9 × 10 6 L/day), 17.9 and 383 ng/g, respectively, in Wàdenswil WWTP with 19,000 inhabitant equivalents (17.2×10 6 L/day), and 23.8 and 1,121 ng/g, respectively, in Dübendorf WWTP with 37,000 inhabitant equivalents (21 × 10 6 L/day) (Zhang et al. 2010 "
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