Eva Jakobsson - Academia.edu (original) (raw)
Papers by Eva Jakobsson
Synthesis and analysis of chlorinated naphthalenes : biological and environmental implications
Polybrominated diphenylethers (PBDEs): A novel calss of developmental neurotoxicants in our envir... more Polybrominated diphenylethers (PBDEs): A novel calss of developmental neurotoxicants in our environment.
Toxicological Sciences, 2003
Journal of Chromatography A, 1993
A method was developed for the transfer of fat, polychlorinated biphenyls (PCBs), naphthalenes (P... more A method was developed for the transfer of fat, polychlorinated biphenyls (PCBs), naphthalenes (PCNs), dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) from blood plasma into the lipophilic gel Lipidex 5000. Subsequent elution of the gel separated about 70% of the fat from the analytes. Different adsorbents and activated charcoal were applied for further purification of the sample and separation of analytes. Identification and determination of the chlorinated compounds were made by gas chromatography with electron-capture detection (GC-ECD) or gas chromatography-mass spectrometry (GC-MS). Recoveries were studied by addition of Halowax 1014 and different congeners of PCBs, PCNs, PCDDs and PCDFs to 50 ml of plasma. The mean recoveries of the individual compounds studied were 72-99%. By using the liquid-gel partitioning technique emulsions were avoided. Concentrations of lipids in plasma obtained by the present method agreed well with the concentrations obtained using liquid-liquid partitioning with chloroform-methanol.
Crystal Research and Technology, 2008
A seven‐coordinate Mn(II) complex of N,N,N ′,N ′‐tetrakis[(2‐benzimidazolyl)methyl]‐1,2‐cyclohexa... more A seven‐coordinate Mn(II) complex of N,N,N ′,N ′‐tetrakis[(2‐benzimidazolyl)methyl]‐1,2‐cyclohexanediamine (CDTB), namely, [Mn(CDTB)(DMF)](Pic)2·C2H5OH was synthesized and characterized by elemental analyses, IR spectra and X‐ray single‐crystal diffraction. The complex crystallizes in a typical hybrid organic‐inorganic pattern. The crystal belongs to the monoclinic system, space group P 2 (1) / n with cell constants a = 13.3343(6) Å, b = 33.7015(16) Å, c = 13.7286(6) Å, β = 108.9990(10)°, Z = 4. The structure was solved by direct methods and refined to R = 0.0561 (wR2 = 0.1172). The structure analysis reveals that the Mn(II) has a capped octahedron geometry with seven‐coordination mode, furthermore, the [Mn(CDTB)(DMF)]2+ building blocks were extended into well‐ordered supramolecular networks by complementary hydrogen bonds, and the linkers of the ethanol molecules and the picrate anions play an important role in the self‐assembly process. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, We...
Archives of Environmental Contamination and Toxicology, 2000
Environmental Health Perspectives, 1999
Polybrominated diphenyl ethers (PBDEs) are used as additives in polymers and teiles to prohibit t... more Polybrominated diphenyl ethers (PBDEs) are used as additives in polymers and teiles to prohibit the development offires. Because ofthe production and use of PBDEs, the lipophilic haracteristics, and persistence, these compounds have become ubiquitous environmental con aminants. The aim of the present study was to determine potential exposures of PBDE to derks working filltime at computer screen and persomnnel at an elecnics-disntling plant, with hospitl deaners as a control group. Five PBDE congeners-2,2',4,4'-tetraBDE; 2,2',4,4',5,5'-hexaBDE; 2,2',4,4',5,6'-hexBDEE; 2,2',3,4,4',5',6-heptaBDE; and decaBDE-were quantified in blood serum from all three categories of workers. Subjects woring at the dismanting plt showed significantly higher levels of all PBDE congeners in their serum as compared to the control group. Decabromodiphenyl eier is present in concentrations of 5 pmollg lipid weight (1w) in the personnel dmantling ectronics; these concentratons are comple to the concentrations of2,2',4,4'-tetraBDE. The later compound was the do ting PBDE congener in the derks and deaners. The major compound in personnel at the dismantling plant was 2,2',3,4,4t,5',6-heptaBDE. Concentrations of this PBDE congener are almost twice as high as for 2,2',4,4'-tetraBDE in these workers and seventy times the levl ofthis heptaBDE in deaners. The totl median PBDE concen trations in the serum from workers at the electonics-dismanlding plant, derks, and deaners were 37, 7.3, and 5.4 pmollg lw, respectively. The results show that decabromodiphenyl ether is bioavailable and that occupational exposure to PBDEs occurs at the electronics-dismantding plant. IGy work analysis, blood, contamination, DBDE, decabromodiphenyl ether, electronics recycing, flame nts, levels, occupational exposure, PBDE, persistent organic pollutants, polybrominated diphenyl ethers. Environ Healt Pmpect 107:643-648 (1999).
The Handbook of Environmental Chemistry
Polychlorinated naphthalenes (PCNs) are a group of 75 chlorinated naphthalenes that are structura... more Polychlorinated naphthalenes (PCNs) are a group of 75 chlorinated naphthalenes that are structurally similar to PCBs. Until the 1970s, PCNs were high-volume chemicals commercially produced as mixtures of several congeners marketed under Halowax and other commercial trade names. Total global output of PCNs was estimated at 150,000 metric tonnes until production ceased in Europe and North America in the 1980s.
Acta Chemica Scandinavica, 1994
Toxicological Sciences, 2002
Polybrominated diphenyl ethers (PBDEs) are used in large quantities as flame retardant additives.... more Polybrominated diphenyl ethers (PBDEs) are used in large quantities as flame retardant additives. In a recent study, we have seen that neonatal exposure to some brominated flame retardants can cause permanent aberrations in spontaneous motor behavior that seem to worsen with age. In view of an increasing amount of PBDEs in mother's milk and in the environment, the present study was undertaken to investigate whether there is a critical and limited phase, during neonatal life, for induction of persistent neurotoxic effects of 2,2,4,4,5-pentaBDE (PBDE 99). Neonatal NMRI male mice were exposed on day 3, 10, or 19 to 8 mg 2,2,4,4,5-pentaBDE/kg body weight. Uptake and retention of 2,2,4,4,5-penta[ 14 C]BDE were studied in the mouse brain after exposure to 1.5 M becquerel (Bq) 2,2,4,4,5-penta[ 14 C]BDE /kg body weight (bw) on postnatal day 3, 10, or 19. Spontaneous motor behavior was observed in 4-month-old mice. Mice exposed to 2,2,4,4,5-pentaBDE on day 3 or 10 showed significantly impaired spontaneous motor behavior, whereas no effect was seen in mice exposed on day 19. Neonatal mice exposed to 2,2,4,4,5penta[ 14 C]BDE 99 on postnatal day 3, 10, or 19 were sacrificed 24 h or 7 days posttreatment. The amount of radioactivity, given as per mille (‰) of total amount administered, was between 3.7 and 5.1‰ in the three different age categories at 24 h after administration. Seven days after the administration, 2,2,4,4,5penta[ 14 C]BDE or its metabolites could still be detected in the brain. The amount of radioactivity in the brain was not higher in mice exposed on day 3 or 10 when compared to exposure on day 19. Thus, the behavioral disturbances observed in adult mice following neonatal exposure to 2,2,4,4,5-pentaBDE are induced during a defined critical period of neonatal brain development.
Journal of Chromatography A, 1993
Abstract A gel permeation chromatographic method was developed for the isolation and determinatio... more Abstract A gel permeation chromatographic method was developed for the isolation and determination of small amounts of polychlorinated naphthalenes (PCNs) present in polychlorinated biphenyl (PCB) products. The method was applied to nine commercial ...
Journal of Chromatography A, 1997
Electron-acceptor-bonded stationary phases, 2-(nitrophenyl)ethylsilyl (NPE) and 3-(p-nitrophenoxy... more Electron-acceptor-bonded stationary phases, 2-(nitrophenyl)ethylsilyl (NPE) and 3-(p-nitrophenoxy)propylsilyl (NPO), and electron-donor-bonded phases, 3-(N-carbazolyl)propylsilyl (CZP), 2-(1-pyrenyl)ethylsilyl (PYE), and 5coronenylpentylsilyl (COP), were prepared from silica particles and their selectivities were examined in both polar and non-polar solvents for specific isomers of polychlorodibenzo-p-dioxins (PCDDs), hexachloronaphthalenes (HxCNs) and planar and non-planar polychlorobiphenyl (PCB) congeners. Although no single stationary phase was able to separate all the isomer pairs that are coproduced during the synthesis of the PCDDs and HxCNs, pairs can be separated by selecting a suitable stationary phase and solvent. The separation of mixtures of PCDD isomers were found to be most successful with PYE and NPO phases, which yielded the opposite elution orders for each isomer pair that is produced as a mixture. Similar results were obtained for the HxCN isomers that were separated on PYE and CZP phases. The COP phase provided easier separation of non-ortho-substituted and mono-ortho-substituted PCBs from the other PCBs based on the planarity than PYE phase.
Journal of Chromatography A, 1994
Six commercially available gas chromatography columns were investigated for performance in separa... more Six commercially available gas chromatography columns were investigated for performance in separating polychlorinated naphthalenes (PCNs). Retention behaviour on the investigated phases is compared and retention data for 40 congeners on a 5% phenyl-methylpolysiloxane column is reported. For all columns, except the octylmethylpolysiloxane and the smectic, a relation between substitution pattern and retention was found, where substitution in adjacent positions as well as cu-substitution increase the retention time. A mathematical model based on these findings was developed and used to predict the relative retention of all congeners from di-up to octachloronaphthalene, on a 5% phenyl-methylpolysiloxane column.
Environmental Science & Technology, 1999
Polybrominated diphenyl ethers (PBDEs) are widely used as additive flame retardants in, for examp... more Polybrominated diphenyl ethers (PBDEs) are widely used as additive flame retardants in, for example, textiles, computers, television sets, and other electrical appliances. PBDEs are ubiquitous environmental contaminants, present also in humans. The environmental levels of the PBDEs are, however, still in general lower than those of polychlorinated biphenyls (PCBs). However, while the levels of PCBs generally are decreasing, those of the PBDEs are increasing in, for example, human milk. In the present study 32 individual PBDE congeners were synthesized and characterized. Physicochemical parameters including melting points and UV, 1 H NMR, and mass spectra are reported. Twenty-nine monobrominated to heptabrominated diphenyl ethers were synthesized by the coupling between four diphenyliodonium salts and nine phenolates. One tetrabromodiphenyl ether and two hexabromodiphenyl ethers were synthesized by bromination of two different PBDEs. Twenty-one of the PBDEs and two of the iodonium salts, 2,2′,4,4′-tetrabromodiphenyliodonium chloride and 3,3′,4,4′tetrabromodiphenyliodonium chloride, are to the authors' knowledge described for the first time. These synthesized reference compounds will aid in the identification and quantification of PBDEs present in environmental samples and will allow further assessment of PBDE toxicity.
Environmental Health Perspectives, 2001
Brominated flame retardants are a novel group of global environmental contaminants. Within this g... more Brominated flame retardants are a novel group of global environmental contaminants. Within this group the polybrominated diphenyl ethers (PBDE) constitute one class of many that are found in electrical appliances, building materials, and textiles. PBDEs are persistent compounds that appear to have an environmental dispersion similar to that of polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT). Levels of PBDEs are increasing in mother´s milk while other organohalogens have decreased in concentration. We studied for developmental neurotoxic effects two polybrominated diphenylethers, 2,2´,4,4´-tetrabromodiphenyl ether (PBDE 47) and 2,2´,4,4´,5-pentabromodiphenylether (PBDE 99)-congeners that dominate in environmental and human samples-together with another frequently used brominated flame retardant, tetrabromo-bis-phenol-A (TBBPA). The compounds were given to 10-day-old NMRI male mice, as follows: PBDE 47, 0.7 mg (1.4 µmol), 10.5 mg (21.1 µmol)/kg body weight (bw); PBDE 99, 0.8 mg (1.4 µmol), 12.0 mg (21.1 µmol)/kg bw; TBBPA, 0.75 mg (1.4 µmol), 11.5 mg (21.1 µmol)/kg bw. Mice serving as controls received 10 mL/kg bw of the 20% fat emulsion vehicle in the same manner. The present study has shown that neonatal exposure to PBDE 99 and PBDE 47 can cause permanent aberrations in spontaneous behavior, evident in 2-and 4month-old animals. This effect together with the habituation capability was more pronounced with increasing age, and the changes were dose-response related. Furthermore, neonatal exposure to PBDE 99 also affected learning and memory functions in adult animals. These are developmental defects that have been detected previously in connection with PCBs.
Chemosphere, 2004
A method was developed for studies of the phototransformation at UV irradiation of aqueous soluti... more A method was developed for studies of the phototransformation at UV irradiation of aqueous solutions of tetrabromobisphenol A (TBBPA), tribromobisphenol A (TriBBPA), tetrachlorobisphenol A (TCBPA), 2,4-dichlorophenol at various pHs as well as 2-chlorophenol, 2-bromophenol, 3,4-dichlorophenol and bisphenol A at pH 11. The absorbance spectra of the compounds and the emission spectra of the light-source were determined and used to calculate disappearance quantum yields of the photochemical reactions that were taking place. No major differences between the disappearance quantum yields of TBBPA and TCBPA were observed at pH 10, while the disappearance quantum yield of TriBBPA was approximately two times higher. The rate of decomposition of TBBPA was six times higher at pH 8 than at pH 6. Identification of the degradation products of TBBPA and TriBBPA, by GC-MS analysis and by comparison to synthesised reference compounds, indicated that TBBPA and TriBBPA decompose via different mechanisms. Three isopropylphenol derivatives; 4-isopropyl-2,6-dibromophenol, 4-isopropylene-2,6-dibromophenol and 4-(2-hydroxyisopropyl)-2,6-dibromophenol, were identified as major degradation products of TBBPA while the major degradation product of TriBBPA was tentatively identified as 2-(2,4-cyclopentadienyl)-2-(3,5-dibromo-4hydroxyphenyl)propane.
Archives of Toxicology, 1994
The 7-ethoxyresorufin O-deethylase (EROD)- and aryl hydrocarbon hydroxylase (AHH)-inducing potenc... more The 7-ethoxyresorufin O-deethylase (EROD)- and aryl hydrocarbon hydroxylase (AHH)-inducing potencies and lethalities of a technical preparation of polychlorinated naphthalenes (PCNs) (Halowax 1014, approximate congener ratio: 20% tetrachloronaphthalenes, 40% pentachloronaphthalenes, 40% hexachloronaphthalenes), a mixture of 50% 1,2,3,5,6,7-hexachloronaphthalene and 50% 1,2,3,4,6,7-hexachloronaphthalene (HxCN-mix), and 1,2,3,4,5,6,7-heptachloronaphthalene (HpCN) were studied in chicken (Gallus domesticus) and eider duck (Somateria mollissima) embryos. Mortality and hepatic EROD activity were determined on day 10 of incubation in chicken embryos exposed to various doses of the PCNs via the air-sacs of the eggs on day 7. The HxCN-mix and Halowax 1014 proved to have both embryolethal and EROD-inducing properties, while the HpCN had low EROD-inducing potency and embryolethality. ED50 values for EROD induction by the HxCN-mix and Halowax 1014 were estimated to be 0.06 mg/kg egg and 0.2 mg/kg egg, respectively. Fifty percent of the chicken embryos died (6/12) when given 3.0 mg/kg of the HxCN-mix while a similar dose of Halowax 1014 caused mortality in 4 out of 12 chicken embryos. The dose-response curve for EROD induction by Halowax 1014 exhibited a decline after the maximal level was reached. When Halowax 1014 (1.0 mg/kg egg) was coinjected with 3,3',4,4',5-pentachlorobiphenyl (PCB IUPAC #126) (0.1 microgram/kg egg) no additive effects on EROD activity were found, but when the same dose of Halowax 1014 was coinjected with a dose of PCB #126, known to cause maximal induction (1.0 microgram/kg egg), the resulting EROD activity was lower than that caused solely by 1.0 micrograms PCB #126/kg egg.(ABSTRACT TRUNCATED AT 250 WORDS)
Fresenius' Journal of Analytical Chemistry, 1993
In an attempt to develop non-destructive work-up procedures for monitoring lipophilic pollutants ... more In an attempt to develop non-destructive work-up procedures for monitoring lipophilic pollutants in the air by analysis of pine needle epicuticular wax, a project was undertaken to identify substances that interfere with the normal gas-chromatographic quantitations. Epicuticular wax was extracted from needles of radiata pine and processed to remove the bulk estolides and resin and fatty acids. Fractionation of the
Synthesis and analysis of chlorinated naphthalenes : biological and environmental implications
Polybrominated diphenylethers (PBDEs): A novel calss of developmental neurotoxicants in our envir... more Polybrominated diphenylethers (PBDEs): A novel calss of developmental neurotoxicants in our environment.
Toxicological Sciences, 2003
Journal of Chromatography A, 1993
A method was developed for the transfer of fat, polychlorinated biphenyls (PCBs), naphthalenes (P... more A method was developed for the transfer of fat, polychlorinated biphenyls (PCBs), naphthalenes (PCNs), dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) from blood plasma into the lipophilic gel Lipidex 5000. Subsequent elution of the gel separated about 70% of the fat from the analytes. Different adsorbents and activated charcoal were applied for further purification of the sample and separation of analytes. Identification and determination of the chlorinated compounds were made by gas chromatography with electron-capture detection (GC-ECD) or gas chromatography-mass spectrometry (GC-MS). Recoveries were studied by addition of Halowax 1014 and different congeners of PCBs, PCNs, PCDDs and PCDFs to 50 ml of plasma. The mean recoveries of the individual compounds studied were 72-99%. By using the liquid-gel partitioning technique emulsions were avoided. Concentrations of lipids in plasma obtained by the present method agreed well with the concentrations obtained using liquid-liquid partitioning with chloroform-methanol.
Crystal Research and Technology, 2008
A seven‐coordinate Mn(II) complex of N,N,N ′,N ′‐tetrakis[(2‐benzimidazolyl)methyl]‐1,2‐cyclohexa... more A seven‐coordinate Mn(II) complex of N,N,N ′,N ′‐tetrakis[(2‐benzimidazolyl)methyl]‐1,2‐cyclohexanediamine (CDTB), namely, [Mn(CDTB)(DMF)](Pic)2·C2H5OH was synthesized and characterized by elemental analyses, IR spectra and X‐ray single‐crystal diffraction. The complex crystallizes in a typical hybrid organic‐inorganic pattern. The crystal belongs to the monoclinic system, space group P 2 (1) / n with cell constants a = 13.3343(6) Å, b = 33.7015(16) Å, c = 13.7286(6) Å, β = 108.9990(10)°, Z = 4. The structure was solved by direct methods and refined to R = 0.0561 (wR2 = 0.1172). The structure analysis reveals that the Mn(II) has a capped octahedron geometry with seven‐coordination mode, furthermore, the [Mn(CDTB)(DMF)]2+ building blocks were extended into well‐ordered supramolecular networks by complementary hydrogen bonds, and the linkers of the ethanol molecules and the picrate anions play an important role in the self‐assembly process. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, We...
Archives of Environmental Contamination and Toxicology, 2000
Environmental Health Perspectives, 1999
Polybrominated diphenyl ethers (PBDEs) are used as additives in polymers and teiles to prohibit t... more Polybrominated diphenyl ethers (PBDEs) are used as additives in polymers and teiles to prohibit the development offires. Because ofthe production and use of PBDEs, the lipophilic haracteristics, and persistence, these compounds have become ubiquitous environmental con aminants. The aim of the present study was to determine potential exposures of PBDE to derks working filltime at computer screen and persomnnel at an elecnics-disntling plant, with hospitl deaners as a control group. Five PBDE congeners-2,2',4,4'-tetraBDE; 2,2',4,4',5,5'-hexaBDE; 2,2',4,4',5,6'-hexBDEE; 2,2',3,4,4',5',6-heptaBDE; and decaBDE-were quantified in blood serum from all three categories of workers. Subjects woring at the dismanting plt showed significantly higher levels of all PBDE congeners in their serum as compared to the control group. Decabromodiphenyl eier is present in concentrations of 5 pmollg lipid weight (1w) in the personnel dmantling ectronics; these concentratons are comple to the concentrations of2,2',4,4'-tetraBDE. The later compound was the do ting PBDE congener in the derks and deaners. The major compound in personnel at the dismantling plant was 2,2',3,4,4t,5',6-heptaBDE. Concentrations of this PBDE congener are almost twice as high as for 2,2',4,4'-tetraBDE in these workers and seventy times the levl ofthis heptaBDE in deaners. The totl median PBDE concen trations in the serum from workers at the electonics-dismanlding plant, derks, and deaners were 37, 7.3, and 5.4 pmollg lw, respectively. The results show that decabromodiphenyl ether is bioavailable and that occupational exposure to PBDEs occurs at the electronics-dismantding plant. IGy work analysis, blood, contamination, DBDE, decabromodiphenyl ether, electronics recycing, flame nts, levels, occupational exposure, PBDE, persistent organic pollutants, polybrominated diphenyl ethers. Environ Healt Pmpect 107:643-648 (1999).
The Handbook of Environmental Chemistry
Polychlorinated naphthalenes (PCNs) are a group of 75 chlorinated naphthalenes that are structura... more Polychlorinated naphthalenes (PCNs) are a group of 75 chlorinated naphthalenes that are structurally similar to PCBs. Until the 1970s, PCNs were high-volume chemicals commercially produced as mixtures of several congeners marketed under Halowax and other commercial trade names. Total global output of PCNs was estimated at 150,000 metric tonnes until production ceased in Europe and North America in the 1980s.
Acta Chemica Scandinavica, 1994
Toxicological Sciences, 2002
Polybrominated diphenyl ethers (PBDEs) are used in large quantities as flame retardant additives.... more Polybrominated diphenyl ethers (PBDEs) are used in large quantities as flame retardant additives. In a recent study, we have seen that neonatal exposure to some brominated flame retardants can cause permanent aberrations in spontaneous motor behavior that seem to worsen with age. In view of an increasing amount of PBDEs in mother's milk and in the environment, the present study was undertaken to investigate whether there is a critical and limited phase, during neonatal life, for induction of persistent neurotoxic effects of 2,2,4,4,5-pentaBDE (PBDE 99). Neonatal NMRI male mice were exposed on day 3, 10, or 19 to 8 mg 2,2,4,4,5-pentaBDE/kg body weight. Uptake and retention of 2,2,4,4,5-penta[ 14 C]BDE were studied in the mouse brain after exposure to 1.5 M becquerel (Bq) 2,2,4,4,5-penta[ 14 C]BDE /kg body weight (bw) on postnatal day 3, 10, or 19. Spontaneous motor behavior was observed in 4-month-old mice. Mice exposed to 2,2,4,4,5-pentaBDE on day 3 or 10 showed significantly impaired spontaneous motor behavior, whereas no effect was seen in mice exposed on day 19. Neonatal mice exposed to 2,2,4,4,5penta[ 14 C]BDE 99 on postnatal day 3, 10, or 19 were sacrificed 24 h or 7 days posttreatment. The amount of radioactivity, given as per mille (‰) of total amount administered, was between 3.7 and 5.1‰ in the three different age categories at 24 h after administration. Seven days after the administration, 2,2,4,4,5penta[ 14 C]BDE or its metabolites could still be detected in the brain. The amount of radioactivity in the brain was not higher in mice exposed on day 3 or 10 when compared to exposure on day 19. Thus, the behavioral disturbances observed in adult mice following neonatal exposure to 2,2,4,4,5-pentaBDE are induced during a defined critical period of neonatal brain development.
Journal of Chromatography A, 1993
Abstract A gel permeation chromatographic method was developed for the isolation and determinatio... more Abstract A gel permeation chromatographic method was developed for the isolation and determination of small amounts of polychlorinated naphthalenes (PCNs) present in polychlorinated biphenyl (PCB) products. The method was applied to nine commercial ...
Journal of Chromatography A, 1997
Electron-acceptor-bonded stationary phases, 2-(nitrophenyl)ethylsilyl (NPE) and 3-(p-nitrophenoxy... more Electron-acceptor-bonded stationary phases, 2-(nitrophenyl)ethylsilyl (NPE) and 3-(p-nitrophenoxy)propylsilyl (NPO), and electron-donor-bonded phases, 3-(N-carbazolyl)propylsilyl (CZP), 2-(1-pyrenyl)ethylsilyl (PYE), and 5coronenylpentylsilyl (COP), were prepared from silica particles and their selectivities were examined in both polar and non-polar solvents for specific isomers of polychlorodibenzo-p-dioxins (PCDDs), hexachloronaphthalenes (HxCNs) and planar and non-planar polychlorobiphenyl (PCB) congeners. Although no single stationary phase was able to separate all the isomer pairs that are coproduced during the synthesis of the PCDDs and HxCNs, pairs can be separated by selecting a suitable stationary phase and solvent. The separation of mixtures of PCDD isomers were found to be most successful with PYE and NPO phases, which yielded the opposite elution orders for each isomer pair that is produced as a mixture. Similar results were obtained for the HxCN isomers that were separated on PYE and CZP phases. The COP phase provided easier separation of non-ortho-substituted and mono-ortho-substituted PCBs from the other PCBs based on the planarity than PYE phase.
Journal of Chromatography A, 1994
Six commercially available gas chromatography columns were investigated for performance in separa... more Six commercially available gas chromatography columns were investigated for performance in separating polychlorinated naphthalenes (PCNs). Retention behaviour on the investigated phases is compared and retention data for 40 congeners on a 5% phenyl-methylpolysiloxane column is reported. For all columns, except the octylmethylpolysiloxane and the smectic, a relation between substitution pattern and retention was found, where substitution in adjacent positions as well as cu-substitution increase the retention time. A mathematical model based on these findings was developed and used to predict the relative retention of all congeners from di-up to octachloronaphthalene, on a 5% phenyl-methylpolysiloxane column.
Environmental Science & Technology, 1999
Polybrominated diphenyl ethers (PBDEs) are widely used as additive flame retardants in, for examp... more Polybrominated diphenyl ethers (PBDEs) are widely used as additive flame retardants in, for example, textiles, computers, television sets, and other electrical appliances. PBDEs are ubiquitous environmental contaminants, present also in humans. The environmental levels of the PBDEs are, however, still in general lower than those of polychlorinated biphenyls (PCBs). However, while the levels of PCBs generally are decreasing, those of the PBDEs are increasing in, for example, human milk. In the present study 32 individual PBDE congeners were synthesized and characterized. Physicochemical parameters including melting points and UV, 1 H NMR, and mass spectra are reported. Twenty-nine monobrominated to heptabrominated diphenyl ethers were synthesized by the coupling between four diphenyliodonium salts and nine phenolates. One tetrabromodiphenyl ether and two hexabromodiphenyl ethers were synthesized by bromination of two different PBDEs. Twenty-one of the PBDEs and two of the iodonium salts, 2,2′,4,4′-tetrabromodiphenyliodonium chloride and 3,3′,4,4′tetrabromodiphenyliodonium chloride, are to the authors' knowledge described for the first time. These synthesized reference compounds will aid in the identification and quantification of PBDEs present in environmental samples and will allow further assessment of PBDE toxicity.
Environmental Health Perspectives, 2001
Brominated flame retardants are a novel group of global environmental contaminants. Within this g... more Brominated flame retardants are a novel group of global environmental contaminants. Within this group the polybrominated diphenyl ethers (PBDE) constitute one class of many that are found in electrical appliances, building materials, and textiles. PBDEs are persistent compounds that appear to have an environmental dispersion similar to that of polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT). Levels of PBDEs are increasing in mother´s milk while other organohalogens have decreased in concentration. We studied for developmental neurotoxic effects two polybrominated diphenylethers, 2,2´,4,4´-tetrabromodiphenyl ether (PBDE 47) and 2,2´,4,4´,5-pentabromodiphenylether (PBDE 99)-congeners that dominate in environmental and human samples-together with another frequently used brominated flame retardant, tetrabromo-bis-phenol-A (TBBPA). The compounds were given to 10-day-old NMRI male mice, as follows: PBDE 47, 0.7 mg (1.4 µmol), 10.5 mg (21.1 µmol)/kg body weight (bw); PBDE 99, 0.8 mg (1.4 µmol), 12.0 mg (21.1 µmol)/kg bw; TBBPA, 0.75 mg (1.4 µmol), 11.5 mg (21.1 µmol)/kg bw. Mice serving as controls received 10 mL/kg bw of the 20% fat emulsion vehicle in the same manner. The present study has shown that neonatal exposure to PBDE 99 and PBDE 47 can cause permanent aberrations in spontaneous behavior, evident in 2-and 4month-old animals. This effect together with the habituation capability was more pronounced with increasing age, and the changes were dose-response related. Furthermore, neonatal exposure to PBDE 99 also affected learning and memory functions in adult animals. These are developmental defects that have been detected previously in connection with PCBs.
Chemosphere, 2004
A method was developed for studies of the phototransformation at UV irradiation of aqueous soluti... more A method was developed for studies of the phototransformation at UV irradiation of aqueous solutions of tetrabromobisphenol A (TBBPA), tribromobisphenol A (TriBBPA), tetrachlorobisphenol A (TCBPA), 2,4-dichlorophenol at various pHs as well as 2-chlorophenol, 2-bromophenol, 3,4-dichlorophenol and bisphenol A at pH 11. The absorbance spectra of the compounds and the emission spectra of the light-source were determined and used to calculate disappearance quantum yields of the photochemical reactions that were taking place. No major differences between the disappearance quantum yields of TBBPA and TCBPA were observed at pH 10, while the disappearance quantum yield of TriBBPA was approximately two times higher. The rate of decomposition of TBBPA was six times higher at pH 8 than at pH 6. Identification of the degradation products of TBBPA and TriBBPA, by GC-MS analysis and by comparison to synthesised reference compounds, indicated that TBBPA and TriBBPA decompose via different mechanisms. Three isopropylphenol derivatives; 4-isopropyl-2,6-dibromophenol, 4-isopropylene-2,6-dibromophenol and 4-(2-hydroxyisopropyl)-2,6-dibromophenol, were identified as major degradation products of TBBPA while the major degradation product of TriBBPA was tentatively identified as 2-(2,4-cyclopentadienyl)-2-(3,5-dibromo-4hydroxyphenyl)propane.
Archives of Toxicology, 1994
The 7-ethoxyresorufin O-deethylase (EROD)- and aryl hydrocarbon hydroxylase (AHH)-inducing potenc... more The 7-ethoxyresorufin O-deethylase (EROD)- and aryl hydrocarbon hydroxylase (AHH)-inducing potencies and lethalities of a technical preparation of polychlorinated naphthalenes (PCNs) (Halowax 1014, approximate congener ratio: 20% tetrachloronaphthalenes, 40% pentachloronaphthalenes, 40% hexachloronaphthalenes), a mixture of 50% 1,2,3,5,6,7-hexachloronaphthalene and 50% 1,2,3,4,6,7-hexachloronaphthalene (HxCN-mix), and 1,2,3,4,5,6,7-heptachloronaphthalene (HpCN) were studied in chicken (Gallus domesticus) and eider duck (Somateria mollissima) embryos. Mortality and hepatic EROD activity were determined on day 10 of incubation in chicken embryos exposed to various doses of the PCNs via the air-sacs of the eggs on day 7. The HxCN-mix and Halowax 1014 proved to have both embryolethal and EROD-inducing properties, while the HpCN had low EROD-inducing potency and embryolethality. ED50 values for EROD induction by the HxCN-mix and Halowax 1014 were estimated to be 0.06 mg/kg egg and 0.2 mg/kg egg, respectively. Fifty percent of the chicken embryos died (6/12) when given 3.0 mg/kg of the HxCN-mix while a similar dose of Halowax 1014 caused mortality in 4 out of 12 chicken embryos. The dose-response curve for EROD induction by Halowax 1014 exhibited a decline after the maximal level was reached. When Halowax 1014 (1.0 mg/kg egg) was coinjected with 3,3',4,4',5-pentachlorobiphenyl (PCB IUPAC #126) (0.1 microgram/kg egg) no additive effects on EROD activity were found, but when the same dose of Halowax 1014 was coinjected with a dose of PCB #126, known to cause maximal induction (1.0 microgram/kg egg), the resulting EROD activity was lower than that caused solely by 1.0 micrograms PCB #126/kg egg.(ABSTRACT TRUNCATED AT 250 WORDS)
Fresenius' Journal of Analytical Chemistry, 1993
In an attempt to develop non-destructive work-up procedures for monitoring lipophilic pollutants ... more In an attempt to develop non-destructive work-up procedures for monitoring lipophilic pollutants in the air by analysis of pine needle epicuticular wax, a project was undertaken to identify substances that interfere with the normal gas-chromatographic quantitations. Epicuticular wax was extracted from needles of radiata pine and processed to remove the bulk estolides and resin and fatty acids. Fractionation of the