Determination Of Perfluorooctanoic Acid Research Articles

Dispersive solid phase extraction of perfluorooctanoic acid from wastewater using chromium-doped CoFe layered double hydroxide for determination by LC-MS/MS

Polyfluoroalkyl substances (PFAS) are persistently dangerous substances in the environment, threatening human health even in very low concentrations. This work introduced a dispersive solid phase extraction (DSPE) based on Cr-doped CoFe layered double hydroxide (LDH), which was used as the extraction phase for the effective removal of perfluorooctanoic acid (PFOA) from wastewater samples. Cr-doped CoFe LDH was synthesized using the facile co-precipitation method. Successful partial substitution of Fe3+ by Cr3+ cations in the crystalline lattice of CoFe LDH was affirmed by energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and elemental dot-mapping analysis. Layered morphology was observed for both bare and Cr-doped CoFe LDH in scanning and transmission electron microscopy images. The influence of diverse parameters, including sorbent mass, eluent solvent type, volume of eluent, agitation mode, adsorption time, and pH, was assessed on the extraction of PFOA by Cr-doped CoFe LDH. The experimental data from the effective DSPE followed by liquid chromatography–tandem mass spectrometry exhibited a low limit of detection of 0.03 µg/L, broad linear range (0.1–300 µg/L and R2 ≥ 0.997), and good repeatability (6.7 %, n = 5 intraday) for the enrichment and determination of PFOA in wastewater samples.

Determination of Perfluorooctanoic Acid (PFOA) in the Indoor Dust Matter of the Sicily (Italy) Area: Analysis and Exposure Evaluations.

Perfluorooctanoic acid (PFOA) in environmental matrices is increasingly being studied due to its environmental persistence, global occurrence, bioaccumulation, and associated human health risks. Some indoor environments can significantly impact the health of occupants due to pollutants in indoor air and household dust. To investigate the potential exposure of individuals to PFOA in specific confined environments, this study reports an analytical method and results concerning the determination of PFOA in household dust, used as a passive sampler. To the best of our knowledge, this paper represents one of the first studies concerning PFOA concentrations in indoor dust collected in the south of Italy, within the European region. A total of twenty-three dust samples were collected from two different areas of Sicily (Palermo and Milena), extracted, and analyzed by an UHPLC-QTOF-MS/MS system. Finally, PFOA exposure was estimated using a new index (Indoor PFOA Exposure Index, IPEX) that incorporates the PFOA levels in dust, exposure time, and the correlation between the PFOA in dust and blood. It was then compared across four different exposure groups, revealing that PFOA exposure for people working in chemistry laboratories was evaluated to be ten times higher than the exposure for homemakers.

Determination of Perfluorooctanoic Acid and Perfluorooctane Sulfonate Water Quality Criteria for Ecosystem Protection of Laguna Lake, Philippines

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are organic chemicals which pose concerns in the environment due to their persistence and bioaccumulative properties. This study used Assessment Factors and Species Sensitivities Distributions to derive specific thresholds to protect the ecosystem in the Laguna Lake, Philippines from risks posed by the toxicity of PFOS and PFOA using available ecotoxicity data for local species. For Assessment Factor method, the U.S. Environmental Protection Agency guideline for the narrative Tier II criteria was suitable based on the available toxicity data with calculated maximum concentration threshold for PFOS and PFOA of 0.51 and 0.75 mg L-1, respectively, and continuous maximum concentration values of 0.06 and 0.08 mg L-1, respectively. For the methods using Species Sensitivity Distribution (SSD), PFOS and PFOA thresholds extrapolated using factors for small datasets were 0.046 and 0.088 mg L-1, respectively. Lastly, PFOS and PFOA Hazardous Concentration (HC5) extrapolated from the weighted average SSD model estimates were 0.061 and 0.078 mg L-1, respectively. The results can serve as the first regulatory and risk assessment basis for aquatic ecosystem protection against risks posed by emerging contaminants in the lake.

Determination of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) contents of compost amended soils and plants grown in these soils

ABSTRACT Dietary intake is a major route of exposure to perfluorinated compounds. In the case of exposure to these compounds by nutrition, the consumption of agricultural products is one of the most important places. Biological wastes are converted into composts and are often used for fertiliser purposes to prevent spreading of waste to large areas. These practices cause agricultural areas to be contaminated with perfluorinated compounds and to first pass on to the plants growing on these soils and then to animals and infestations through the food chain. In this study, firstly, perfluorooctanoic acid (PFOA) and perfluorooctane sulphonic acid (PFOS) levels were determined in five different composts. Mean PFOA and PFOS concentrations were between 26.1–102.0 ng g−1 and 0.211–0.649 ng g−1, respectively. After sowing wheat and corn, compost was applied. The amount of PFOA and PFOS that passed to the stalks, leaves, and grains of wheat and corn was determined. Obtained results showed that the total perfluorinated compounds migration decreased as follows: stalk>leaf>grain. Furthermore, the effects of PFOA and PFOS on chlorophyll concentration and soluble protein were examined. A decrease in chlorophyll formation and soluble protein content was observed with increasing PFOA and PFOS concentrations.

Determination of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in livestock feeds

The objective of this study was to examine the levels of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in livestock feeds (calf starter, dairy cattle, fattening cattle, calf growth, lamb starter, lamb growth, dairy sheep, fattening sheep, chick, broiler and layer hen feeds) and feed raw materials (wheat, cottonseed pulp, wheat bran, maize, barley, lentil, wheat straw, bean straw, pea straw and meadow grass). PFOA and PFOS concentrations of 30 livestock feeds, 24 raw feed materials, 9 poultry feeds and 10 water samples were determined by LC-MS/MS. The findings indicated that all the evaluated livestock feeds and feed materials contain perfluorinated compounds. Poultry, cattle, feed raw materials and sheep feed samples were examined for PFOA concentrations and for PFOS concentrations, cattle, poultry, sheep and feed raw materials samples were examined. The highest PFOA concentrations were found in layer hen feed (7.55 μg/kg), dairy cattle feed (6.75 μg/kg) and fattening cattle feed (6.53 μg/kg) respectively. The highest PFOS levels were found in layer hen feed (0.882 μg/kg), calf feed (0.833 μg/kg) and dairy sheep feed (0.830 μg/kg). Keywords : Feed, feed raw materials, LC-MS/MS, perfluorinated compound

Suitability of Wild Boar (Sus scrofa) as a Bioindicator for Environmental Pollution with Perfluorooctanoic Acid (PFOA) and Perfluorooctanesulfonic Acid (PFOS).

Wildlife species, such as roe deer, moose, brown hare, wild boar, etc., are known to accumulate persistent environmental contaminants and thus are useful as bioindicators for environmental pollution. Wild boars become exposed to perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) from flora, fauna, water, and soil. The main exposure pathway to PFOA and PFOS is assumed to be the oral intake. From studies in domestic pigs (belonging to the same species Sus scrofa), it has been established that the oral exposure results in the liver accumulation of PFOA and PFOS. Thus, we posit that wild boars can be quantitatively used as suitable bioindicators for the presence of these substances in the environment. After the environmental pollution case in the Hessian region Sauerland in 2006, monitoring programs of individual Federal States from 2007 to 2013 showed that almost all wild boar liver samples contained PFOA and PFOS. In 2014, the analyses of PFOA and PFOS in liver of wild boars hunted in the south, north, and west of Germany showed liver concentrations at the same level among regions. Overall, an average ratio of PFOS:PFOA concentration in liver of 20.5:1 was found. To estimate the actual ratio of PFOS:PFOA in the wild boars' dietary exposure, we performed toxicokinetic modeling. According to the model, the PFOS exposure is only 2.2 times that of PFOA (because PFOS has slower elimination kinetics and higher affinity for the liver than PFOA). Overall, the determination of PFOA and PFOS in liver of wild boars indicates that both substances are ubiquitously distributed in the environment. At the same time, higher exposures were found for animals living in closer proximity to dense human populations.

Determination of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in food and beverages

ABSTRACTThe determination of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS) in food and beverages sold in Turkey was carried out using liquid chromatography–tandem mass spectrometry (LC-MS/MS). A total of 123 samples of selected food and beverages such as fish, meat, offal, egg, cracker, chips, cake, chocolate, vegetable, milk and juice were examined. The highest PFOA concentrations were determined in cow meat (5.15 ng g−1), cow kidney (5.65 ng g−1), cow spleen (5.06 ng g−1) and chicken liver (5.02 ng g−1). The highest PFOS levels were found in horse mackerel (52.43 ng g−1), pike-perch (45.87 ng g−1), sardine (42.83 ng g−1) and black cod (41.33 ng g−1). Fish was found to be major source of the PFOS intake, while meat and offal were found to be major sources of the PFOA intake.

Development of a certified reference material for the determination of perfluorooctanoic acid

A certified reference material (CRM) for the determination of perfluorooctanoic acid (PFOA) has been issued as NMIJ CRM 4056-a by the National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology (NMIJ/AIST). Purity (kg kg -1 ) based on a titration method was determined by subtracting the mass fractions of impurities measured using liquid chromatography/mass spectrometry (LC/MS) from those of acids expressed as PFOA measured by a neutralization potentiometric titration. To validate an obtained result, purity based on a mass balance method was determined by subtracting the mass fractions of impurities, measured using LC/MS, Karl-Fischer titration (KFT), and vacuum evapo- ration, from 1 kg kg -1 . Results from both titration and mass balance methods were in agreement within the accepted limits of uncertainty. The certified purity of NMIJ CRM 4056-a was determined to be 0.959 kg kg -1 , calculated as the mean of the results obtained with the two methods. The standard uncertainty of the certified purity was evaluated from purity evaluations as well as from sample homogeneity and stability obtained from LC/MS and KFT analyses. Consequently, the expanded uncertainty was estimated to be 0.005 kg kg -1 with a coverage factor of k = 2.

Determination of perfluorooctanoic acid and perfluorooctane sulfonate in cooking oil and pig adipose tissue using reversed-phase liquid–liquid extraction followed by high performance liquid chromatography tandem mass spectrometry

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are two perfluorinated compounds (PFCs) ubiquitously present in the environment, which could pose potential adverse effects on human health. Contamination and presence of PFOA and PFOS should be eliminated or rigidly restricted in food stuffs such as cooking oils and lard (from pig adipose tissue). This work describes a rapid, simple, reliable and sensitive method for quantitative analysis of PFOA and PFOS in cooking oils and pig adipose tissue with liquid chromatography tandem mass spectrometry (LC–MS/MS). The pretreatment mainly included a one-step reversed-phase liquid–liquid extraction using the mixture of basified water/methanol as the aqueous system, and dichloromethane (DCM) as the non-polar system. PFOA and PFOS can be successfully separated from the two lipid-rich matrices, i.e., cooking oil and adipose tissue, and extracted into the aqueous system, and then directly analyzed with LC–MS/MS. This method was validated in terms of accuracy (both intra- and inter-batch), precision, recovery, linearity, sensitivity and applicability. The intra-batch accuracies for PFOA and PFOS in cooking oil samples were within 93.9–101.9% with relative standard deviation (RSD) no more than 10.9%, and the inter-batch accuracies were 91.2–96.2% with RSD not exceeding 10.0%. The intra-batch accuracies of the analytes in pig adipose tissue samples were 102.9–113.0% with RSD of 8.8–13.1%. And the quantification ranges of PFOA and PFOS were 0.01–25ng/mL. This method has been applied to the analysis of PFOA and PFOS in real samples collected from local markets in Guangzhou, China.

Determination of Perfluorooctanoic Acid and Perfluorooctane Sulfonate in Lake Victoria Gulf Water

In this study we present a report of investigation from the screening of perfluorooctanoic acid and perfluorooctane sulfonate in Lake Victoria Gulf and in its source rivers. The first determined levels of perfluorinated alkylated substances in Lake Victoria ecosystem are presented. Variability in the concentrations of perfluorooctanoic acid or perfluorooctane sulfonate in river waters (range perfluorooctanoic acid 400-96,400 and perfluorooctane sulfonate <400-13,230 pg/L) was higher than for Lake waters (range perfluorooctanoic acid 400-11,650 and perfluorooctane sulfonate <400-2,530 pg/L respectively) suggesting generalized point sources such as domestic and industrial waste. The lowest limit of quantification was 400 pg/L for both analytes and limit of detection were 75 and 40 pg/L for perfluorooctanoic acid and perfluorooctane sulfonate respectively. Typical values for precision obtained were 0.14-3.7%, with concentrations range from 400 pg/mL to 1 microg/mL).

Determination of perfluorooctanoic acid and perfluorooctanesulfonate in human tissues by liquid chromatography/single quadrupole mass spectrometry

A method is described that permits the measurement of the levels of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in human liver, kidney, adipose tissue, brain, basal ganglia, hypophysis, thyroid, gonads, pancreas, lung, skeletal muscle and blood, even in subjects not occupationally exposed to these compounds. The purification of samples involved the use of trifunctional (tC18) and strong anion-exchange (SAX) solid-phase extraction cartridges, and the analysis utilized a high-performance liquid chromatograph coupled to a single quadrupole mass spectrometer (LC/MS). The analyses were conducted on a mixed-bed reversed-phase column by gradient runs using 3 mM ammonium acetate/methanol mixtures at different proportions as the mobile phase. The detector was used in electrospray negative ion mode by recording simultaneously the ions m/z 413.0 (PFOA) and 499.0 (PFOS). Perfluorononanoic acid (PFNA), added to the samples before the purification, was used as the internal standard (ion monitored = m/z 463.6). The recovery rates of the extraction procedure ranged from 79.6 to 95.6% (CV% 1.7-7.4%) for PFOA, from 79.7 to 100.8% (CV% = 1.2-7.1) for PFOS, and from 89.1 to 102.3% (CV% = 0.9-5.2 %) for PFNA. The calibration curves were linear up to at least 400 ng of analytes per gram of tissue. The detection limits (signal-to-noise ratio = 3) were 0.1 ng/g for both PFOA and PFOS measured in all tissues except adipose tissue, where the limits were about 0.2 ng/g. The content of analytes in tissues varied from 0.3 to 3.8 ng/g (respectively: basal ganglia and lung) for PFOA, and from 1.0 to 13.6 ng/g (respectively: skeletal muscle and liver) for the linear isomer of PFOS. The method is suitable to evaluate the content of PFOA and PFOS in different tissues taken from the general population exposed to very low concentrations of these pollutants.

Method for the Determination of Perfluorooctanoic Acid in Air Samples Using Liquid Chromatography with Mass Spectrometry

Perfluorooctanoic acid is a completely fluorinated carbo-xylic acid that is usually used in the ammonium salt form as a processing aid in the production of many fluoropolymers and fluoroelastomers. Ammonium perfluorooctanoate readily dissociates in water to give the ammonium and perfluorooctanoate ions. Perfluorooctanoate has been reported to be present in low levels in human serum in the United States and Europe. This study reports on the development and validation of a method for the determination of perfluorooctanoic acid in air samples. This method uses the Occupational Safety and Health Administration (OSHA) Versatile Sampler (OVS) with a nominal 0.3 μ m filter and polystyrene resin sorbent (XAD-2 or XAD-4) followed by determination of the perfluorooctanoate anion by liquid chromatography mass spectrometry. The method was validated in the range of 0.474 to 47.4 μ g/m3 for a 480-L sample. Breakthrough studies showed samples could be collected at 1 L/min for 24 hours or at 15 L/min up to 8 hours without breakthrough. Extract storage stability tests showed that sample extracts in methanol remain stable in glass autosampler vials for up to 13 days following initial injection. Perfluorooctanoic acid stability on OVS tubes was unaffected at both refrigerated and ambient temperatures. The overall average retention efficiency was 92.1% with a pooled RSD95 of 5.8% at five concentration levels (0.474 μ g/m3 to 47.4 μ g/m3).

Determination of perfluorooctanoic acid (PFOA) extractable from the surface of commercial cookware under simulated cooking conditions by LC/MS/MS

Salts of pentadecafluorooctanoic acid (PFOA) are polymerization aids used in the manufacture of fluoropolymers; one of the applications of fluoropolymers is the coating of metal cookware products. A method was developed to determine if PFOA might be present in and extracted from the surface of commercial frying pans coated with a DuPont fluoropolymer under simulated cooking conditions. Commercial grade cookware was obtained, then extracted with water and ethanol/water mixtures at 100 and 125 degrees C, and the resulting extracts were analyzed by liquid chromatography tandem mass spectrometry (LC/MS/MS). Detection and quantification limits as low as 100 pg cm(-2) were demonstrated. None of the fluoropolymer treated cookware samples analyzed showed detectable levels of PFOA when extracted under simulated cooking conditions.