Determination Of Perfluorinated Compounds Research Articles

Development of styrene-divinylbenzene copolymer beads using QuEChERS for simultaneous detection and quantification of 13 perfluorinated compounds in aquatic samples

In this work, a reliable and affordable QuEChERS sampling method is developed for simultaneous detection and quantification of 13 perfluorinated compounds (PFCs) in aquatic products. Liquid chromatography/tandem mass spectrometry (LC-MS/MS) was used for rapid analysis and the analytes were extracted using styrene-divinylbenzene copolymer (PS-DVB). The performances of the sorbents were evaluated based upon parameters, such as recovery and matrix effect. Under optimized conditions, the limits of detection of 13 PFCs were found to be lying within the range of 0.001–0.070 μg kg−1. The application of aquatic sampling demonstrated that ultra-trace levels of PFCs were successfully detected and quantified within the range of 0.028–31.0 μg kg−1 in tilapia (Oreochromis niloticus), salmon (Oncorhynchus mykiss), mussels (Perna viridis) and clam (Ruditapes philippinarum). Compared with the solid phase extraction method, the application of PS-DVB beads as an adsorbent proved to be quicker and successful in the determination of PFCs in aquatic samples.

Simultaneous analysis of 14 short- and long-chain perfluorinated compounds in water by liquid chromatography-tandem mass spectrometry using solid phase extraction

A solid phase extraction (SPE)-ultrahigh pressure liquid chromatography (UPLC) method coupled with tandem mass spectrometry was developed for the simultaneous analysis of the 14 short- and long-chain perfluorinated compounds (PFCs) in water. Water sample was concentrated and purified through WAX mixed-mode SPE cartridges. The separation of PFCs was performed on a BEH C18 column with gradient elution using methanol-5 mmol/L ammonium acetate as mobile phases. The PFCs were quantified by internal standard method in multiple-reaction monitoring mode. The calibration curves of the 14 PFCs were linear in the range of 0.1-50 μg/L with the correlation coefficients > 0.99. The limits of detection (S/N = 3) and quantitation (S/N = 10) of the method were 0.09-1.15 ng/L and 0.29-3.85 ng/L, respectively. The average recoveries of eight PFCs at three spiked levels of 2, 10 and 20 ng/L were 85.0%, 120.2% and 117.4%, with the relative standard deviations of 9.2%, 9.0% and 6.6%, respectively. The recoveries of the rest six PFCs were low due to unavoidable strong adsorption on the bottle/tube walls during sample pretreatment. The method was applied in the determination of PFCs in real samples of a lake in South China. Four short-chain and five long-chain PFCs were detected with mass concentrations of 41.29-49.05 ng/L and 98.43-111.02 ng/L, respectively. The results show that the method is suitable for the simultaneous analysis of short- and long-chain perfluorinated compounds in environmental water.

Chitosan-Coated Octadecyl-Functionalized Magnetite Nanoparticles: Preparation and Application in Extraction of Trace Pollutants from Environmental Water Samples

In the present study, chitosan-coated octadecyl-functionalized magnetite nanoparticles (Fe(3)O(4)-C(18)-chitosan MNPs) are synthesized and used as an adsorbent to extract trace analytes from environmental water samples. The magnetic nanoparticles, 20 nm in diameter, are of uniform size and have a high magnetic saturation value of 52 emu g(-1), which endue the adsorbent with a large surface area and convenience of isolation. The anionic pollutants, perfluorinated compounds (PFCs), are trapped by the octadecyl group of the interior hydrophobic layer. The positively charged chitosan polymer coating also contributes to PFC enrichment. At the same time, the coating improves the dispersibility of MNPs in aqueous solution and enhances the anti-interference ability of the adsorbent to natural organic macromolecules in complex samples by size exclusion or electrostatic repulsion. A liquid chromatography-tandem mass spectrometry system is employed in the determination of PFCs after preconcentration with the MNP adsorbent. The predominant factors affecting preconcentration are investigated and optimized. Under the selected conditions, concentration factors of 1000 are achieved by extracting the analytes from 500 mL of several environmental water samples and concentrating the eluants to 0.5 mL with a nitrogen flow. The method detection limits obtained for perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), perluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), and perfluorotetradecanoic acid (PFTA) in Gaobeidian wastewater are 0.24, 0.093, 0.24, 0.14, 0.075, 0.24, and 0.17 ng L(-1), respectively. Recoveries of PFOA, PFOS, PFNA, PFDA, PFUnDA, PFDoDA, and PFTA are in the ranges of 88-108%, 63-112%, 79-109%, 56-107%, 66-106%, 56-106%, and 66-103% for four spiked water samples with low relative standard deviation (2-8%), which indicates good method precision. The advantages of this novel adsorbent are high extraction efficiency, anti-interference, and convenient operation.

Significant improvements in the analysis of perfluorinated compounds in water and fish: Results from an interlaboratory method evaluation study

The 2nd international interlaboratory study (ILS) on perfluorinated compounds (PFCs) in environmental samples was organized to assess the performance of 21 North American and European laboratories on the analysis of PFCs in water and fish. A study protocol was provided to assess accuracy, precision, matrix effects and to study the use of in-house standards. The participants used shared native and mass-labelled standards that were provided for this study to quantify the PFC concentrations in the samples. Matrix effects in the determination of PFCs can be considerable and can decrease the sensitivity, the accuracy and internal standard recoveries. Therefore, two quantification methods were evaluated by all laboratories: standard addition quantification (SAQ) and solvent-based calibration curve quantification (SBCCQ; using mass-labelled internal standards (IS)). The between laboratory reproducibility (i.e. coefficient of variance) was smaller for the SBCCQ results (except for PFBS and PFHxS for which no mass-labelled analogues were available) compared to those obtained by the SAQ method. The within laboratory precision of individual laboratories is good (mean for all PFCs in water 12% and 6.8% in fish). The good performance is partially attributable to the use of well-defined native- and mass-labelled standards. Therefore, the SBCCQ method is recommended. The results show that analytical methods for PFCs in water and fish have improved considerably. Critical steps identified in this study are (i) the use of well-defined native standards for quantification, (ii) the use of mass-labelled internal standards (preferably one for each target compound) and (iii) minimization of matrix effects by a better clean up.