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Asbjørn Svardal - One of the best experts on this subject based on the ideXlab platform.
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Gas chromatography-mass spectrometry analysis of Alkylphenols in produced water from offshore oil installations as pentafluorobenzoate derivatives.
Journal of chromatography. A, 2004Co-Authors: Stepan Boitsov, Jarle Klungsøyr, Sonnich Meier, Asbjørn SvardalAbstract:A simple, highly selective and sensitive method for the determination of 14 representative Alkylphenols from phenol (C0) to nonylphenol (C9) in produced water is described. Solid-phase extraction (SPE) by anion-exchange sorbent is used to extract Alkylphenols from produced water. The samples are then derivatised by pentafluorobenzoyl chloride and analysed on GC-MS (negative ion chemical ionisation, NCI). The derivatisation procedure has been validated by means of two-level factorial design (2(7-4)) experiments. Quantification is done with isotope dilution of five internal standards of different alkyl chain length. The detection limits were at low ng/l levels. A comparison with GC-MS analysis of non-derivatised Alkylphenol samples revealed the advantage of derivatisation as described in the method.
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Gas chromatography–mass spectrometry analysis of Alkylphenols in produced water from offshore oil installations as pentafluorobenzoate derivatives
Journal of Chromatography A, 2004Co-Authors: Stepan Boitsov, Jarle Klungsøyr, Sonnich Meier, Asbjørn SvardalAbstract:Abstract A simple, highly selective and sensitive method for the determination of 14 representative Alkylphenols from phenol (C 0 ) to nonylphenol (C 9 ) in produced water is described. Solid-phase extraction (SPE) by anion-exchange sorbent is used to extract Alkylphenols from produced water. The samples are then derivatised by pentafluorobenzoyl chloride and analysed on GC–MS (negative ion chemical ionisation, NCI). The derivatisation procedure has been validated by means of two-level factorial design (2 7-4 ) experiments. Quantification is done with isotope dilution of five internal standards of different alkyl chain length. The detection limits were at low ng/l levels. A comparison with GC–MS analysis of non-derivatised Alkylphenol samples revealed the advantage of derivatisation as described in the method.
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Effects of Alkylphenols on redox status in first spawning Atlantic cod (Gadus morhua).
Aquatic toxicology (Amsterdam Netherlands), 2004Co-Authors: Linda Hasselberg, Sonnich Meier, Asbjørn SvardalAbstract:Offshore oil production releases large amounts of lipophilic compounds in produced water and into the ocean. The discharge of produced water from the Norwegian petroleum sector has increased from 26 million m3 in 1993 to 120 million m3 in 2001, and it continues to increase. Produced water contains significant amounts of Alkylphenols, which have been reported to be estrogenic, causing endocrine disruption in fish. In year 2000, approximately 44 tons of Alkylphenols were released on the Norwegian continental shelf in connection with discharge of produced water. Except from being estrogenic, relatively little is known about the effects of Alkylphenols when released in the marine environment. Our objective was to study how Alkylphenols affect the redox status in first spawning Atlantic cod (Gadus morhua) of both sexes. Model compounds tested included 4-tert-butylphenol (C4), 4-n-pentylphenol (C5), 4-n-hexylphenol (C6) and 4-n-heptylphenol (C7), all found in produced water. First spawning Atlantic cod were force-fed a mixture of these four Alkylphenols, ranging between 0.02 and 80 ppm or 5 ppm 17beta-estradiol (E2), for 1 or 4 weeks. Increased hepatic total glutathione concentration in response to Alkylphenol exposure was detected in female fish compared to control group after 1-week exposure, an effect not seen after 4 weeks. Furthermore, hepatic total glutathione concentration was sex dependent, where male fish sampled after 4 weeks had higher levels of glutathione than female fish. Increased glutathione reductase catalytic activities in both male and female fish were seen after exposure to 0.02 ppm Alkylphenol mixture in 4 weeks. The glutathione S-transferase activity was only affected in male fish exposed to 0.02 ppm Alkylphenols, and glucose-6-phosphate dehydrogenase activity increased in female fish exposed to 0.02 ppm Alkylphenol mixture for 1 week. The increase of hepatic total glutathione content as well as the effects on glutathione reductase activities suggests that Alkylphenol exposure affects the redox status in Atlantic cod.
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Effects of Alkylphenols on CYP1A and CYP3A expression in first spawning Atlantic cod (Gadus morhua).
Aquatic toxicology (Amsterdam Netherlands), 2004Co-Authors: Linda Hasselberg, Asbjørn Svardal, Sonnich Meier, Tove Hegelund, Malin CelanderAbstract:Abstract Alkylphenols are continuously released into the ocean as a result of offshore oil production. Alkylphenols, including 4-tert-butylphenol (C4), 4n-pentylphenol (C5), 4n-hexylphenol (C6), and 4n-heptylphenol (C7), up to 237 ppb concentrations, have been detected in produced water from oil platforms. Previous studies have shown that Alkylphenols induce vitellogenesis in fish. Atlantic cod (Gadus morhua) of both sexes were force-fed with various doses ranging between 0.02 and 80 ppm of a mixture of Alkylphenols (C4:C5:C6:C7 ratio 1:1:1:1) or 5 ppm 17β-estradiol. We investigated effects on hepatic CYP1A and CYP3A protein expression in protein blots, using antibodies against scup (Stenotomus chrysops) CYP1A1 and rainbow trout (Oncorhynchus mykiss) CYP3A. There was a sexually dimorphic expression of CYP1A and CYP3A protein levels, with females expressing higher levels than males. Treatment of male Atlantic cod with 17β-estradiol resulted in increased CYP1A and CYP3A protein levels. Exposure to Alkylphenols resulted in a dose-dependent increase of CYP1A and CYP3A protein expression in males, but not in females. However, this increase of CYP1A protein levels was not reflected on the CYP1A-mediated ethoxyresorufin-O-deethylase (EROD) activity, implying that Alkylphenols inhibited the CYP1A enzyme activity in vivo. In vitro inhibition studies with pooled liver microsomes from Atlantic cod confirmed that the Alkylphenols mixture efficiently inhibited the CYP1A activity (IC50=10 μM), although the inhibitory effect of each individual Alkylphenol varied. The IC50 values for each individual Alkylphenol on the CYP1A activity were, in a descending order of magnitude: [C7>C6>C5⪢C4], ranging from 12 to 300 μM with decreased length of the 4-alkyl chain. The effect of Alkylphenols on the CYP3A activity in vitro in liver microsomes also was investigated, using the fluorescent 7-benzyloxy-4-[trifluoromethyl]-coumarin (BFC) as a diagnostic CYP3A substrate. The Alkylphenol mixture inhibited CYP3A activity with IC50 value at 100 μM. The IC50 values for each individual Alkylphenol on CYP3A activity were, in a descending order of magnitude: [C5>C6>C7>C4], ranging between 60 and 250 μM. Taken together, our results show that the Alkylphenol mixture and 17β-estradiol resulted in elevated hepatic CYP1A and CYP3A expression in male Atlantic cod. The Alkylphenol mixture strongly inhibited CYP1A activities, whereas it weakly inhibited CYP3A activity in Atlantic cod liver microsomes in vitro. In addition, 17β-estradiol was a weak inhibitor of CYP3A activity (IC50=75 μM) and did not notably inhibit the CYP1A activity in vitro.
Sonnich Meier - One of the best experts on this subject based on the ideXlab platform.
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Identification of estrogen-like Alkylphenols in produced water from offshore oil installations.
Marine environmental research, 2007Co-Authors: Stepan Boitsov, Svein A. Mjøs, Sonnich MeierAbstract:Produced water released into the sea from oil installations contains a vast number of organic compounds. This work focuses on the analysis and identification of phenols in produced water, in particular long-chain para-substituted Alkylphenols, which act as endocrine disruptors for marine biota. Some Alkylphenol standards, unavailable commercially, have been synthesised and some compounds of interest identified. However, a complete identification is not possible since conventional GC techniques cannot achieve the desired degree of separation. An overview of the levels of the 52 known Alkylphenols in produced water from nine oil installations in the North and Norwegian Seas has been made. The previously unidentified Alkylphenols in produced water have been characterised by means of Alkylphenol retention indices (APRI) and mass spectrometry, and their total amounts estimated for the same nine locations. Our results confirm the presence of naphthols and other as yet unidentified compounds in produced water, while thiophenols were not detected by the used technique.
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Alkylphenol retention indices.
Journal of chromatography. A, 2006Co-Authors: Svein A. Mjøs, Sonnich Meier, Stepan BoitsovAbstract:A novel type of retention indices for Alkylphenols and related compounds are proposed. The Alkylphenol retention indices (APRI) use para-substituted n-Alkylphenols as reference series. APRI for para-n-Alkylphenols are per definition equal to the number of carbon atoms in the alkyl substituent; the value for phenol is zero. Application of the APRI system with different types of derivatisation of the phenolic hydroxy group showed that the derivatisation has limited influence on these indices. Especially para-substituted Alkylphenols gave APRI values that could be transferred with high accuracy from one type of derivative to another. By comparing results obtained with different gradients in temperature-programmed GC, it was also shown that APRI is less affected by chromatographic conditions than retention indices based on n-alkanes.
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Gas chromatography-mass spectrometry analysis of Alkylphenols in produced water from offshore oil installations as pentafluorobenzoate derivatives.
Journal of chromatography. A, 2004Co-Authors: Stepan Boitsov, Jarle Klungsøyr, Sonnich Meier, Asbjørn SvardalAbstract:A simple, highly selective and sensitive method for the determination of 14 representative Alkylphenols from phenol (C0) to nonylphenol (C9) in produced water is described. Solid-phase extraction (SPE) by anion-exchange sorbent is used to extract Alkylphenols from produced water. The samples are then derivatised by pentafluorobenzoyl chloride and analysed on GC-MS (negative ion chemical ionisation, NCI). The derivatisation procedure has been validated by means of two-level factorial design (2(7-4)) experiments. Quantification is done with isotope dilution of five internal standards of different alkyl chain length. The detection limits were at low ng/l levels. A comparison with GC-MS analysis of non-derivatised Alkylphenol samples revealed the advantage of derivatisation as described in the method.
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Gas chromatography–mass spectrometry analysis of Alkylphenols in produced water from offshore oil installations as pentafluorobenzoate derivatives
Journal of Chromatography A, 2004Co-Authors: Stepan Boitsov, Jarle Klungsøyr, Sonnich Meier, Asbjørn SvardalAbstract:Abstract A simple, highly selective and sensitive method for the determination of 14 representative Alkylphenols from phenol (C 0 ) to nonylphenol (C 9 ) in produced water is described. Solid-phase extraction (SPE) by anion-exchange sorbent is used to extract Alkylphenols from produced water. The samples are then derivatised by pentafluorobenzoyl chloride and analysed on GC–MS (negative ion chemical ionisation, NCI). The derivatisation procedure has been validated by means of two-level factorial design (2 7-4 ) experiments. Quantification is done with isotope dilution of five internal standards of different alkyl chain length. The detection limits were at low ng/l levels. A comparison with GC–MS analysis of non-derivatised Alkylphenol samples revealed the advantage of derivatisation as described in the method.
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Effects of Alkylphenols on redox status in first spawning Atlantic cod (Gadus morhua).
Aquatic toxicology (Amsterdam Netherlands), 2004Co-Authors: Linda Hasselberg, Sonnich Meier, Asbjørn SvardalAbstract:Offshore oil production releases large amounts of lipophilic compounds in produced water and into the ocean. The discharge of produced water from the Norwegian petroleum sector has increased from 26 million m3 in 1993 to 120 million m3 in 2001, and it continues to increase. Produced water contains significant amounts of Alkylphenols, which have been reported to be estrogenic, causing endocrine disruption in fish. In year 2000, approximately 44 tons of Alkylphenols were released on the Norwegian continental shelf in connection with discharge of produced water. Except from being estrogenic, relatively little is known about the effects of Alkylphenols when released in the marine environment. Our objective was to study how Alkylphenols affect the redox status in first spawning Atlantic cod (Gadus morhua) of both sexes. Model compounds tested included 4-tert-butylphenol (C4), 4-n-pentylphenol (C5), 4-n-hexylphenol (C6) and 4-n-heptylphenol (C7), all found in produced water. First spawning Atlantic cod were force-fed a mixture of these four Alkylphenols, ranging between 0.02 and 80 ppm or 5 ppm 17beta-estradiol (E2), for 1 or 4 weeks. Increased hepatic total glutathione concentration in response to Alkylphenol exposure was detected in female fish compared to control group after 1-week exposure, an effect not seen after 4 weeks. Furthermore, hepatic total glutathione concentration was sex dependent, where male fish sampled after 4 weeks had higher levels of glutathione than female fish. Increased glutathione reductase catalytic activities in both male and female fish were seen after exposure to 0.02 ppm Alkylphenol mixture in 4 weeks. The glutathione S-transferase activity was only affected in male fish exposed to 0.02 ppm Alkylphenols, and glucose-6-phosphate dehydrogenase activity increased in female fish exposed to 0.02 ppm Alkylphenol mixture for 1 week. The increase of hepatic total glutathione content as well as the effects on glutathione reductase activities suggests that Alkylphenol exposure affects the redox status in Atlantic cod.
Sylvie Barraud - One of the best experts on this subject based on the ideXlab platform.
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Priority substances in accumulated sediments in a stormwater detention basin from an industrial area
Environmental Pollution, 2018Co-Authors: Laure Wiest, Sylvie Barraud, Robert Baudot, Florent Lafay, Erik Bonjour, Céline Becouze-lareure, Jean-baptiste Aubin, Patrick Jame, Gislain Lipeme Kouyi, Christel SebastianAbstract:One of the most adopted solutions in developed countries to manage stormwater is detention/retention basins which generate large quantities of sediments that have to be removed regularly. In order to manage them properly, accurate data are needed about their physical and chemical characteristics, particularly on micropollutant concentrations and their associated risk. This work consisted in a two-year sampling of dry sediments from a detention-settling basin. Priority substances, including pesticides, polybrominated diphenyl ethers (PBDE), Alkylphenols and bisphenol A (BPA), were monitored. Different sites in the basin bottom were sampled in order to investigate spatial distribution of the contamination. Results show that the increase of the sediment thickness in the basin was heterogeneous with a maximum of 15 cm after two years. Pesticides and PBDE were, if detected, mainly found in low concentrations from 2 ng/g to 286 ng/g. Conversely, Alkylphenols and bisphenol A were always quantified at concentrations varying from 6 ng/g to 3400 ng/g. These high levels suggest that these sediments should be managed with precautions. Spatial heterogeneity of Alkylphenol ethoxylates and BPA concentrations was observed, with higher contamination of Alkylphenol ethoxylates in anaerobic zones and BPA levels correlated with total organic carbon and in a lesser extent to fine particles.
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event based quantification of emerging pollutant removal for an open stormwater retention basin loads efficiency and importance of uncertainties
Water Research, 2015Co-Authors: C Sebastian, Celine Becouzelareure, Lipeme G Kouyi, Sylvie BarraudAbstract:Abstract Up to now, emerging contaminants have not been further-studied in in-situ stormwater best management practices and especially in detention basins. In this article, the efficiency of a dry stormwater detention basin was investigated regarding the removal of 7 Alkylphenols and Alkylphenol ethoxylates, 9 polybrominated diphenyl ethers, 45 pesticides and bisphenol A. Concentrations of contaminants were obtained by chemical analysis on dissolved and particulate phase distinctly. The removal efficiency was assessed on total, dissolved and particulate phase accounting for the global chain of uncertainty with a 95% confidence interval. Results showed that pesticides (rather hydrophilic) are not trapped in the detention basin but are released contrarily to B209 which is mostly in particulate phase. Alkylphenols and Alkylphenol ethoxylates are present in both phases and the efficiency is storm event-dependent. Uncertainty consideration in efficiency determination revealed efficiency data, usually presented by raw values are not relevant to conclude on the performance of a detention basin. In this case study, efficiency data with a 95% confidence interval indicate that only 35%, 50% and 41% of campaigns showed an impact (in trapping or releasing) of the detention basin on Alkylphenols and ethoxylates, polybrominated diphenyl ethers and pesticides respectively.
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Event-based quantification of emerging pollutant removal for an open stormwater retention basin – Loads, efficiency and importance of uncertainties
Water Research, 2015Co-Authors: C Sebastian, G. Lipeme Kouyi, C. Becouze-lareure, Sylvie BarraudAbstract:Up to now, emerging contaminants have not been further-studied in in-situ stormwater best management practices and especially in detention basins. In this article, the efficiency of a dry stormwater detention basin was investigated regarding the removal of 7 Alkylphenols and Alkylphenol ethoxylates, 9 polybrominated diphenyl ethers, 45 pesticides and bisphenol A. Concentrations of contaminants were obtained by chemical analysis on dissolved and particulate phase distinctly. The removal efficiency was assessed on total, dissolved and particulate phase accounting for the global chain of uncertainty with a 95% confidence interval. Results showed that pesticides (rather hydrophilic) are not trapped in the detention basin but are released contrarily to B209 which is mostly in particulate phase. Alkylphenols and Alkylphenol ethoxylates are present in both phases and the efficiency is storm event-dependent. Uncertainty consideration in efficiency determination revealed efficiency data, usually presented by raw values are not relevant to conclude on the performance of a detention basin. In this case study, efficiency data with a 95% confidence interval indicate that only 35%, 50% and 41% of campaigns showed an impact (in trapping or releasing) of the detention basin on Alkylphenols and ethoxylates, polybrominated diphenyl ethers and pesticides respectively.
Stepan Boitsov - One of the best experts on this subject based on the ideXlab platform.
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Identification of estrogen-like Alkylphenols in produced water from offshore oil installations.
Marine environmental research, 2007Co-Authors: Stepan Boitsov, Svein A. Mjøs, Sonnich MeierAbstract:Produced water released into the sea from oil installations contains a vast number of organic compounds. This work focuses on the analysis and identification of phenols in produced water, in particular long-chain para-substituted Alkylphenols, which act as endocrine disruptors for marine biota. Some Alkylphenol standards, unavailable commercially, have been synthesised and some compounds of interest identified. However, a complete identification is not possible since conventional GC techniques cannot achieve the desired degree of separation. An overview of the levels of the 52 known Alkylphenols in produced water from nine oil installations in the North and Norwegian Seas has been made. The previously unidentified Alkylphenols in produced water have been characterised by means of Alkylphenol retention indices (APRI) and mass spectrometry, and their total amounts estimated for the same nine locations. Our results confirm the presence of naphthols and other as yet unidentified compounds in produced water, while thiophenols were not detected by the used technique.
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Alkylphenol retention indices.
Journal of chromatography. A, 2006Co-Authors: Svein A. Mjøs, Sonnich Meier, Stepan BoitsovAbstract:A novel type of retention indices for Alkylphenols and related compounds are proposed. The Alkylphenol retention indices (APRI) use para-substituted n-Alkylphenols as reference series. APRI for para-n-Alkylphenols are per definition equal to the number of carbon atoms in the alkyl substituent; the value for phenol is zero. Application of the APRI system with different types of derivatisation of the phenolic hydroxy group showed that the derivatisation has limited influence on these indices. Especially para-substituted Alkylphenols gave APRI values that could be transferred with high accuracy from one type of derivative to another. By comparing results obtained with different gradients in temperature-programmed GC, it was also shown that APRI is less affected by chromatographic conditions than retention indices based on n-alkanes.
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Gas chromatography-mass spectrometry analysis of Alkylphenols in produced water from offshore oil installations as pentafluorobenzoate derivatives.
Journal of chromatography. A, 2004Co-Authors: Stepan Boitsov, Jarle Klungsøyr, Sonnich Meier, Asbjørn SvardalAbstract:A simple, highly selective and sensitive method for the determination of 14 representative Alkylphenols from phenol (C0) to nonylphenol (C9) in produced water is described. Solid-phase extraction (SPE) by anion-exchange sorbent is used to extract Alkylphenols from produced water. The samples are then derivatised by pentafluorobenzoyl chloride and analysed on GC-MS (negative ion chemical ionisation, NCI). The derivatisation procedure has been validated by means of two-level factorial design (2(7-4)) experiments. Quantification is done with isotope dilution of five internal standards of different alkyl chain length. The detection limits were at low ng/l levels. A comparison with GC-MS analysis of non-derivatised Alkylphenol samples revealed the advantage of derivatisation as described in the method.
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Gas chromatography–mass spectrometry analysis of Alkylphenols in produced water from offshore oil installations as pentafluorobenzoate derivatives
Journal of Chromatography A, 2004Co-Authors: Stepan Boitsov, Jarle Klungsøyr, Sonnich Meier, Asbjørn SvardalAbstract:Abstract A simple, highly selective and sensitive method for the determination of 14 representative Alkylphenols from phenol (C 0 ) to nonylphenol (C 9 ) in produced water is described. Solid-phase extraction (SPE) by anion-exchange sorbent is used to extract Alkylphenols from produced water. The samples are then derivatised by pentafluorobenzoyl chloride and analysed on GC–MS (negative ion chemical ionisation, NCI). The derivatisation procedure has been validated by means of two-level factorial design (2 7-4 ) experiments. Quantification is done with isotope dilution of five internal standards of different alkyl chain length. The detection limits were at low ng/l levels. A comparison with GC–MS analysis of non-derivatised Alkylphenol samples revealed the advantage of derivatisation as described in the method.
C Sebastian - One of the best experts on this subject based on the ideXlab platform.
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event based quantification of emerging pollutant removal for an open stormwater retention basin loads efficiency and importance of uncertainties
Water Research, 2015Co-Authors: C Sebastian, Celine Becouzelareure, Lipeme G Kouyi, Sylvie BarraudAbstract:Abstract Up to now, emerging contaminants have not been further-studied in in-situ stormwater best management practices and especially in detention basins. In this article, the efficiency of a dry stormwater detention basin was investigated regarding the removal of 7 Alkylphenols and Alkylphenol ethoxylates, 9 polybrominated diphenyl ethers, 45 pesticides and bisphenol A. Concentrations of contaminants were obtained by chemical analysis on dissolved and particulate phase distinctly. The removal efficiency was assessed on total, dissolved and particulate phase accounting for the global chain of uncertainty with a 95% confidence interval. Results showed that pesticides (rather hydrophilic) are not trapped in the detention basin but are released contrarily to B209 which is mostly in particulate phase. Alkylphenols and Alkylphenol ethoxylates are present in both phases and the efficiency is storm event-dependent. Uncertainty consideration in efficiency determination revealed efficiency data, usually presented by raw values are not relevant to conclude on the performance of a detention basin. In this case study, efficiency data with a 95% confidence interval indicate that only 35%, 50% and 41% of campaigns showed an impact (in trapping or releasing) of the detention basin on Alkylphenols and ethoxylates, polybrominated diphenyl ethers and pesticides respectively.
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Event-based quantification of emerging pollutant removal for an open stormwater retention basin – Loads, efficiency and importance of uncertainties
Water Research, 2015Co-Authors: C Sebastian, G. Lipeme Kouyi, C. Becouze-lareure, Sylvie BarraudAbstract:Up to now, emerging contaminants have not been further-studied in in-situ stormwater best management practices and especially in detention basins. In this article, the efficiency of a dry stormwater detention basin was investigated regarding the removal of 7 Alkylphenols and Alkylphenol ethoxylates, 9 polybrominated diphenyl ethers, 45 pesticides and bisphenol A. Concentrations of contaminants were obtained by chemical analysis on dissolved and particulate phase distinctly. The removal efficiency was assessed on total, dissolved and particulate phase accounting for the global chain of uncertainty with a 95% confidence interval. Results showed that pesticides (rather hydrophilic) are not trapped in the detention basin but are released contrarily to B209 which is mostly in particulate phase. Alkylphenols and Alkylphenol ethoxylates are present in both phases and the efficiency is storm event-dependent. Uncertainty consideration in efficiency determination revealed efficiency data, usually presented by raw values are not relevant to conclude on the performance of a detention basin. In this case study, efficiency data with a 95% confidence interval indicate that only 35%, 50% and 41% of campaigns showed an impact (in trapping or releasing) of the detention basin on Alkylphenols and ethoxylates, polybrominated diphenyl ethers and pesticides respectively.