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P Haglund

Publications and source records attributed to P Haglund.

17 recordsLinked to original sources
PubMed2006

Identification of markers for PCB exposure in plasma from Swedish construction workers removing old elastic sealants.

The objective of the present study was to identify PCB-indicators of occupational exposure related to the removal of old elastic sealants. Blood samples were collected from workers involved in removing elastic sealants. Samples were also taken from age- and sex-matched controls. A majority of the exposed workers were re-sampled after 10 months. All samples were analysed for 19 PCBs. The levels in the exposed workers were twice as high as those in the controls, 575 and 267 ng g(-1) lipid, respectively, but were essentially unchanged at the second sampling. The PCB patterns also differed. Levels of many less chlorinated PCBs were much higher in the exposed workers, compared to the controls, and principal component analysis (PCA) revealed that easily metabolized PCBs decreased in the exposed workers during the study. This finding indicates that elimination exceeded uptake during the study period, and that the safety information given to the workers had been effective. PCA was also used to identify exposure markers. The relatively persistent PCBs 56/60 and 66, the easily metabolized PCBs 44, 70 and 110 (with vicinal hydrogens in meta/para-positions) and the very persistent PCBs 153 and 180 were found to be good markers for occupational, recent occupational and background (dietary) exposure, respectively. A PCA model based on these markers was equally effective in differentiating between exposed individuals and controls, and between recent and less recent exposure, as a model based on all PCBs.

Air Pollutants↗
PubMed2005

Sorbent-assisted liquid-liquid extraction (Chem-Elut) of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans in the lipid fraction of human blood plasma.

This work compares two lipid extraction methods for determining 24 polychlorinated biphenyls (PCBs), seven dibenzo-p-dioxins (PCDDs) and ten dibenzofurans (PCDFs) in human blood plasma. The first method was based on conventional liquid-liquid partitioning with chloroform-methanol and the other made use of a sorbent (Chem-Elut) to facilitate the partitioning of lipids into a mixture of hexane and 2-propanol. A multi-layer-silica column including acid- and base-impregnated silica gel was used to reduce the amounts of lipid present in the samples before a basic alumina clean-up step and activated carbon fractionation of planar analytes (PCDD/Fs and non-ortho-PCBs) and non-planar analytes (including ortho-chlorinated PCBs). Gas chromatography coupled to high resolution mass spectrometry was used to identify and quantify the analytes in the two fractions. The wet weight based concentrations obtained by the two methods were in agreement but both methods suffer from large organic solvent consumption. The toxic equivalencies derived for PCBs and PCDD/Fs using the two methods were also in agreement. However, the chloroform-methanol method gave slightly higher lipid recoveries, although with greater variation, than the sorbent-assisted method. Nevertheless, despite giving lower lipid recoveries, the sorbent-assisted method has advantages in ease of use and applicability to whole blood samples. The formation of emulsions was avoided with the Chem-Elut method, which probably explains the lower variability in the lipid determinations.

Adsorption↗
PubMed2004

Separation of seventeen 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins and dibenzofurans and 12 dioxin-like polychlorinated biphenyls by comprehensive two-dimensional gas chromatography with electron-capture detection.

Comprehensive two-dimensional gas chromatography (GC x GC) with electron-capture detection (ECD) has been optimized for the separation of seventeen 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins and dibenzofurans and 12 dioxin-like polychlorinated biphenyls, with emphasis on the selection of the first- and second-dimension, commercially available, columns. When eight second-dimension columns were subsequently combined with a 100% methylpolysiloxane stationary phase (DB-1) in the first dimension to create orthogonal conditions, a complete separation of all congeners with different TEF values was obtained with two column combinations, DB-1 x VF-23 and DB-1 x LC-50. When other types of first-dimension columns were used (and orthogonality was partly sacrificed), a DB-XLB column combined with 007-65HT, VF-23 and LC-50 was found to provide a complete separation of all 29 priority congeners. Next, the potential of these three column combinations for real-life analysis was preliminarily studied. With a spiked and fractionated milk extract, DB-XLB x LC-50 was found to be the most powerful column combination, because of the good separation of the 29 priority congeners from each other as well as from the matrix constituents. Quantitative performance (close to three-order linearity; LODs, 30-150 fg injected; R.S.D.s, 1.5-6.5% (n = 10)) was satisfactory.

Benzofurans↗
PubMed2001

Concentrations and fluxes of hexachlorocyclohexanes and chiral composition of alpha-HCH in environmental samples from the southern Baltic Sea.

In summer 1997 and winter 1998, paired boundary air and surface water samples were collected during cruises in the southern Baltic Sea. Simultaneously, deposition samples were taken at Gotland Island, located close to the air-water sampling area. Water samples taken shortly after the flooding of Oder and Wisla Rivers in summer 1997 were also included in the study. Concentrations and gas exchange fluxes of alpha- and gamma-HCH and chiral composition of alpha-HCH were determined. According to fugacity calculations, the HCHs were close to air-sea partitioning equilibrium. The net fluxes varied over time, particularly during summer. Importance of the air to sea removal routes "gross gas deposition" and "wet deposition" were about equal for gamma-HCH, while the scavenging via precipitation was less important for alpha-HCH. Enantiomer fractions were used to estimate the fraction of alpha-HCH in the boundary air layer that had volatilized from the water. During summer, the fraction was approximately 60%, and wintertime significantly less (0-35%). Variations in air mass origin were clearly reflected in net air-sea gas exchange and isomeric and enantiomeric "signatures" in boundary air. The composition of boundary air and precipitation was also variable depending on season.

Air↗
PubMed2001

Fatal intoxications with chloral hydrate.

An alcoholic man, treated with chloral hydrate (CH) syrup to which he was dependent, was discovered comatose and in respiratory arrest. Death occurred on the ninth day of hospitalization following cerebral oedema. A woman, alcohol addicted, depressed, and epileptic was admitted in the Intensive Care Unit with heart and respiratory failure following CH absorption. She died three days later after a deep coma. In these two cases, CH intoxication was confirmed by toxicological analysis: CH and its major metabolite, trichloroethanol (TCE), were identified and determined in serum and urine using headspace-capillary gas chromatography-mass spectrometry. The concentrations measured were compared with those found in previously published fatalities. The analytical method used can be proposed for both clinical and forensic cases.

Adult↗
PubMed2000

Pressurised liquid extraction of polycyclic aromatic hydrocarbons from contaminated soils.

The reliability and efficiency of the pressurised liquid extraction technique (PLE) for extracting polycyclic aromatic hydrocarbons (PAHs) from contaminated soil has been investigated. Experimental design was used to study the influence of seven extraction variables (sample load, solvents used, solvent ratios, pressure, temperature, extraction time, and rinse volume). The results show that large sample loads in combination with small solvent volumes may result in low extraction efficiency. They also indicate that the recovery of low-molecular-mass PAHs is reduced by low extraction temperatures. The exact settings of the other variables are, however, less significant for the extraction efficiency. Repeated extractions at optimised settings of the tested variables show that PLE is an exhaustive extraction technique that generally results in high yields. In addition, extraction of a certified reference material (CRM 103-100) revealed that the method is both accurate and precise. Another finding was that adding the internal standard on top of the soil in the extraction cell causes considerable over-estimation of the concentrations when large samples are extracted with small solvent volumes. This is because the PLE-cell resembles a chromatographic column, so compounds added to the top of the soil layer have a longer distance to travel through the soil compared to the average distance of the native compounds, which are distributed evenly throughout the column. We therefore recommend that the internal standard should be added to the extract immediately after the extraction or, alternatively, carefully mixed with the sample prior to extraction.

Chromatography, Liquid↗
PubMed2000

Discrimination and thermal degradation of toxaphene compounds in capillary gas chromatography when using split/splitless and on-column injection.

Technical toxaphene and a 22-component Reference Mixture were analyzed using capillary gas chromatography with split/splitless injection (SSL) and on-column injection (OC). In both techniques, electron-capture, negative ionization mass spectrometry (ECNI-MS) was used for detection of chlorobornanes, chlorocamphenes and related compounds. Significant discrimination of highly chlorinated congeners was observed as a result of incomplete transfer of these compounds from the vaporizer to the analytical column when using SSL. This resulted in a much lower response for nona- and decachloro congeners than when using OC. In addition, several toxaphene components, especially the chlorobornanes with gem dichloro substitution on the six-member carbon ring, undergo thermal degradation when using SSL. Some of these congeners are major components of technical toxaphene, but generally are not present, except at low concentrations, in environmental and biological samples. Therefore, technical toxaphene may be discriminated and/or degraded differently than toxaphene compounds in environmental samples when using SSL. This results in significant bias of the quantitative data when using the technical material as a reference. OC suffers much less from these deficiencies and, therefore, is a preferable technique for toxaphene analysis.

Boranes↗
PubMed1998

Enantioselective gas chromatography/mass spectrometry of methylsulfonyl PCBs with application to arctic marine mammals.

Four different commercially available cyclodextrin (CD) capillary gas chromatography (GC) columns were tested for the enantioselective separation of nine environmentally persistent atropisomeric 3- and 4-methylsulfonyl PCBs (MeSO2-CBs). The selected columns contained cyclodextrins with various cavity diameters (beta- or gamma-CD), which were methylated and/or tert-butyldimethylsilylated (TBDMS) in the 2,3,6-O-positions. The beta-CD column with TBDMS substituents in all of the 2,3,6-O-positions was by far the most selective column for the MeSO2-CBs tested. Enantiomers of congeners with 3-MeSO2 substitution were more easily separated than those with 4-MeSO2 substitution. The separation also seemed to be enhanced for congeners with the chlorine atoms on the non-MeSO2-containing ring and clustered on one side of the same ring. The 2,3-di-O-methyl-6-O-TBDMS-beta-CD was found to give somewhat better selectivity than the corresponding gamma-CD, in comparison between the two columns, which were identical in all other respects. Enantioselective analysis of arctic ringed seal (Phoca hispida) and polar bear (Ursus maritimus) adipose tissue revealed a strong dominance of certain enantiomers. For example, the enantiomer ratio (ER) of 3-MeSO2-CB149 was 0.32 and < 0.1 in ringed seal blubber and polar bear fat, respectively. These low ER values are indicative of highly enantioselective formation, enantioselective metabolism, enantioselective transport across cell membranes, or a combination of the three in both species. Comparable results for the enantiomeric analysis of MeSO2-CBs in biotic tissue extracts were obtained using two highly selective mass spectrometric techniques, ion trap mass spectrometry/mass spectrometry and electron capture negative ion low-resolution mass spectrometry.

Animals↗
PubMed1990

Isolation of toxic polychlorinated biphenyls by electron donor-acceptor high-performance liquid chromatography on a 2-(1-pyrenyl)ethyldimethylsilylated silica column.

A rapid and simple liquid chromatographic method for the isolation of toxic planar polychlorinated biphenyls from their formulations by electron donor-acceptor high-performance liquid chromatography using a 2-(1-pyrenyl)ethyldimethylsilylated silica column is described. The separation takes less than 15 min and a complete analysis, including quantitation by gas chromatography-mass spectrometry or gas chromatography with electron-capture detection, may be completed in 60 min. Retention data for 105 individual polychlorinated biphenyl congeners are presented and the retention behaviour, as well as the mechanisms of separation, are discussed.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

Search for chlorobornanes in river sediments and in influents and effluents.

In 1997, we collected nine river sediment samples, including one duplicate, from above and below three pulp and paper mills on the Wisconsin River in Wisconsin, USA, and one mill on Beaver Dam Creek in Ontario, Canada. We also obtained twenty split sediment samples from the Wisconsin River that were collected by the US EPA in collaboration with Indiana University. Finally, we collected influent and effluent samples from eight pulp and paper related industries in the US and Canada. We analyzed all sediment and water samples for hexa- through decachlorobornanes. We did not detect any chlorobornanes in most of the sediments. When chlorobornanes were detected, the concentration in sediments below pulp mills were similar to or less than in those from above the same mills. Chlorobornanes could not be detected in any of the influent or effluent samples. Thus, pulp and paper mills and relate facilities are not a source of chlorobornanes.

Camphanes↗
PubMedDate not supplied

Rapid anaerobic degradation of toxaphene in sewage sludge.

We studied the degradation of technical toxaphene in anaerobic sewage sludge from a municipal waste water treatment plant. Chlorobornanes, chlorocamphenes and related compounds were rapidly degraded, with degradation rates in the order of decachloro>nonachloro>octochloro>heptachloro approximately = hexachloro compounds. The half-lives of individual congeners ranged from <1 day to several days. We also studied the degradation of technical toxaphene in previously sterilized sludge (control), and found it was slower than in the anaerobic sludge. The chlorobornanes that degraded most rapidly in the non-sterilized anaerobic sludge were those with gem chloro substitution on the 6-member carbon-ring, including the toxic congeners, Toxicant A and B. Non-gem chloro substituted congeners, like the biologically persistent P26 and P50, also degraded, but less rapidly. Toxaphene degradation in sewage sludge proceeded primarily via reductive dechlorination, leading to HxSed, HpSed, TC2 and other persistent metabolites. Enantioselective determinations indicated little, if any, enantioselectivity in the formation and/or degradation of these compounds. The isomer and enantiomer profiles of the hexa-, hepta-, and octachlorobornanes are similar to those observed in sediment from the Baltic Sea, suggesting that technical toxaphene is the source of these compounds and that its composition was changed via similar anaerobic degradation pathways.

Anaerobiosis↗