77 research outputs found
Helsingør Statement on poly- and perfluorinated alkyl substances (PFASs)
In this discussion paper, the transition from long-chain poly- and perfluorinated alkyl substances (PFASs) to fluorinated alternatives is addressed. Long-chain PFASs include perfluoroalkyl carboxylic acids (PFCAs) with 7 or more perfluorinated carbons, perfluoroalkyl sulfonic acids (PFSAs) with 6 or more perfluorinated carbons, and their precursors. Because long-chain PFASs have been found to be persistent, bioaccumulative and toxic, they are being replaced by a wide range of fluorinated alternatives. We summarize key concerns about the potential impacts of fluorinated alternatives on human health and the environment in order to provide concise information for different stakeholders and the public. These concerns include, amongst others, the likelihood of fluorinated alternatives or their transformation products becoming ubiquitously present in the global environment; the need for more information on uses, properties and effects of fluorinated alternatives; the formation of persistent terminal transformation products including PFCAs and PFSAs; increasing environmental and human exposure and potential of adverse effects as a consequence of the high ultimate persistence and increasing usage of fluorinated alternatives; the high societal costs that would be caused if the uses, environmental fate, and adverse effects of fluorinated alternatives had to be investigated by publicly funded research; and the lack of consideration of non-persistent alternatives to long-chain PFASs
Toxicokinetics of perfluorooctane sulfonate in birds under environmentally realistic exposure conditions and development of a kinetic predictive model
Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in surface waters, sediments, soils and wastewater – A review on concentrations and distribution coefficients
Dose-dependent reactions of Aporrectodea caliginosa to perfluorooctanoic acid and perfluorooctanesulfonic acid in soil
Sorption of Perfluorinated Compounds onto different types of sewage sludge and assessment of its importance during wastewater treatment
Comment on “Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in surface waters, sediments, soils and wastewater – A review on concentrations and distribution coefficients” by Zareitalabad et al. [Chemosphere 91(6) (2013) 725–732]
Relationship between peroxisome proliferator-activated receptor alpha activity and cellular concentration of 14 perfluoroalkyl substances in HepG2 cells
Effect of K2SO4 concentration on extractability and isotope signature (δ13C and δ15N) of soil C and N fractions
Determination of the labile soil carbon (C) and nitrogen (N) fractions and measurement of their isotopic signatures (δ13C and δ15N) has been used widely for characterizing soil C and N transformations. However, methodological questions and comparison of results of different authors have not been fully solved. We studied concentrations and δ13C and δ15N of salt-extractable organic carbon (SEOC), inorganic (N-NH4+ and N-NO3-) and organic nitrogen (SEON) and salt-extractable microbial C (SEMC) and N (SEMN) in 0.05 and 0.5mK2SO4 extracts from a range of soils in Russia. Despite differences in acidity, organic matter and N content and C and N availability in the studied soils, we found consistent patterns of effects of K2SO4 concentration on C and N extractability. Organic C and N were extracted 1.6-5.5 times more effectively with 0.5mK2SO4 than with 0.05mK2SO4. Extra SEOC extractability with greater K2SO4 concentrations did not depend on soil properties within a wide range of pH and organic matter concentrations, but the effect was more pronounced in the most acidic and organic-rich mountain Umbrisols. Extractable microbial C was not affected by K2SO4 concentrations, while SEMN was greater when extracted with 0.5mK2SO4. We demonstrate that the δ13C and δ15N values of extractable non-microbial and microbial C and N are not affected by K2SO4 concentrations, but use of a small concentration of extract (0.05mK2SO4) gives more consistent isotopic results than a larger concentration (0.5m)
Electrochemical degradation of perfluorinated compounds by Ag coated Ti (Ti/Ag) anode: electrode preparation, characterization and application
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