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Perfluoroalkyl substances (PFASs) in food and water from Faroe Islands Texto completo
2013
Diet and drinking water are suggested to be major exposure pathways for perfluoroalkyl substances (PFASs). In this study, food items and water from Faroe Islands sampled in 2011/2012 were analyzed for 11 perfluoroalkyl carboxylic acids (PFCAs) and 4 perfluoroalkane sulfonic acids (PFSAs). The food samples included milk, yoghurt, crème fraiche, potatoes, fish, and fish feed, and the water samples included surface water and purified drinking water. In total, nine PFCAs and four PFSAs were detected. Generally, the levels of PFAS were in the lower picogram per gram range. Perfluorobutanoic acid was a major contributor to the total PFASs concentration in water samples and had a mean concentration of 750 pg/L. Perfluoroundecanoic acid (PFUnDA) was predominating in milk and wild fish with mean concentrations of 170 pg/g. Perfluorooctane sulfonic acid (PFOS) was most frequently detected in food items followed by PFUnDA, perfluorononanoic acid, and perfluorooctanoic acid (PFOA). Levels of PFUnDA and PFOA exceeded those of PFOS in milk and fish samples. Prevalence of long-chain PFCAs in Faroese food items and water is confirming earlier observations of their increase in Arctic biota. Predominance of short-chain and long-chain homologues indicates exposure from PFOS and PFOA replacement compounds.
Mostrar más [+] Menos [-]On-line preconcentration/determination of zinc from water, biological and food samples using synthesized chelating resin and flame atomic absorption spectrometry Texto completo
2013
Yılmaz, Sibel | Tokalıoğlu, Şerife | Şahan, Serkan | Ülgen, Ahmet | Şahan, Ahmet | Soykan, Cengiz
An on-line flow injection pre-concentration-flame atomic absorption spectrometry method was developed to determine trace zinc in water (tap, dam, and well water), biological (hair and nail), and liver samples. As a solid phase extractant, a synthesized new chelating resin, poly(2-thiozylmethacrylamide-co-divinylbenzene-co-2-acrylamido-2-methyl-1-propane sulfonic acid) was used. The resin was characterized by Fourier transform infrared spectroscopy, elemental analysis, and surface area by nitrogen sorption. A pre-concentration factor of 40-fold for a sample volume of 12.6mL was obtained by using the time-based technique. The detection limit for the pre-concentration method was found to be 2.2μgL⁻¹. The precision (as RSD,%) for 10 replicate determinations at the 0.04μgmL⁻¹ Zn concentration was 1.2%. The calibration graph using the pre-concentration system for zinc was linear with a correlation coefficient of 0.998 in the concentration range from 0.005 to 0.05μgmL⁻¹. The applicability and accuracy of the developed method were estimated by the analysis spiked water, biological, liver samples (83–105%), and also certified reference material TMDA-70 (fortified lake water) and SPS-WW1 Batch 111-Wastewater. The results were in agreement with the certified values.
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