| 1. |
- Claeson, Anna-Sara, 1974-, et al.
(författare)
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Development of a LC-MS/MS method for the analysis of volatile primary and secondary amines as NIT (naphthylisothiocyanate) derivatives
- 2004
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Ingår i: Analytical and Bioanalytical Chemistry. - : Springer. - 1618-2642 .- 1618-2650. ; 378:4, s. 932-939
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Tidskriftsartikel (refereegranskat)abstract
- High-performance liquid chromatography with mass spectrometric detection was used for the structure elucidation of eighteen primary and secondary amines and ammonia derivatised with naphthylisothiocyanate (NIT). A fragmentation scheme was established using reference compounds and the scheme was applied to real air samples from a tyre repair shop and from the air above a bacterial culture. The sampling was performed using a solid sorbent, XAD-2, impregnated with NIT, and the derivatives were extracted with acetonitrile and analysed with LC-MS/MS. A three-step process was developed for screening and identifying of volatile amines. The first step, selected reaction monitoring; SRM was applied in order to screen the samples for NIT derivatives. In the second step, a precursor ion scan gave the [M+H]+ ion, and in the third step a product ion scan gave the fragments needed for identification. The detection limits varied between 0.12 and 0.25 ng μL−1 when screening for unknown derivatised amines. It was possible to separate and identify all the amines with the structural information obtained and the method proved to be general, sensitive and well suited for sampling and analysis of complex environmental samples.
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| 2. |
- Claeson, Anna-Sara, 1974-, et al.
(författare)
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Effects on perceived air quality and symptoms of exposure to microbially produced metabolites and compounds emitted from damp building materials
- 2009
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Ingår i: Indoor Air. - : The Authors Journal compilation. - 0905-6947 .- 1600-0668. ; 19:2, s. 102-112
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Tidskriftsartikel (refereegranskat)abstract
- This work investigated perceived air quality and health effects fromexposure to low to high levels of volatile organic compounds (VOCs) emittedfrom damp building materials and a mixture of molds growing on the materials.A mixture of Wallemia sebi, Fusarium culmorum, Penicillium chrysogenum,Ulocladium botrytis, and Aspergillus versicolor was inoculated on pine wood andparticle board. In Study 1, each of 27 participants took part in two exposureconditions, one with air from molds growing on building materials (low levels ofemissions from the building materials and the mold mixture) and one with blankair, both conditions during 60 min. In Study 2, each of 24 participants wasexposed (10 min) four times in a 2 · 2 design randomly to air from moldybuilding materials (high levels) and blank, with and without nose-clip. Theparticipants rated air quality and symptoms before, during, and after eachexposure. Self-reported tear-film break-up time and attention and processingspeed (Study 1) was also measured. Exposure to high VOC levels increased thereports of perceived poor air quality, and in the condition without nose-clipenhanced skin symptoms were also noted. No such outcome was observed whenexposing the participants to low VOC levels.
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| 3. |
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| 4. |
- Claeson, Anna-Sara, 1974-, et al.
(författare)
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Volatile metabolites from microorganisms grown on humid building materials and synthetic media
- 2002
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Ingår i: Journal of Environmental Monitoring. - : Royal Society of Chemistry. - 1464-0325 .- 1464-0333. ; 4:5, s. 667-672
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Tidskriftsartikel (refereegranskat)abstract
- Growth of different microorganisms is often related to dampness in buildings. Both fungi and bacteria produce complicated mixtures of volatile organic compounds that include hydrocarbons, alcohols, ketones, sulfur- and nitrogen-containing compounds etc. Microbially produced substances are one possible explanation of odour problems and negative health effects in buildings affected by microbial growth. A mixture of five fungi, Aspergillus versicolor, Fusarium culmorum, Penicillium chrysogenum, Ulocladium botrytis and Wallemia sebi were grown on three different humid building materials (pinewood, particle board and gypsum board) and on one synthetic medium. Six different sampling methods were used, to be able to collect both non-reactive volatile organic compounds and reactive compounds such as volatile amines, aldehydes and carboxylic acids. Analysis was performed using gas chromatography, high-performance liquid chromatography and ion chromatography, mass spectrometry was used for identification of compounds. The main microbially produced metabolites found on pinewood were ketones (e.g. 2-heptanone) and alcohols (e.g. 2-methyl-1-propanol). Some of these compounds were also found on particle board, gypsum board and the synthetic medium, but there were more differences than similarities between the materials. For example, dimethoxymethane and 1,3,5-trioxepane and some nitrogen containing compounds were found only on particle board. The metabolite production on gypsum board was very low, although some terpenes (e.g. 3-carene) could be identified as fungal metabolites. On all materials, except gypsum board, the emission of aldehydes decreased during microbial growth. No low molecular weight carboxylic acids were identified.
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| 5. |
- Claeson, Anna-Sara, 1974-
(författare)
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Volatile organic compounds from microorganisms : identification and health effects
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Damp building materials are subjected to degradation processes due to moisture and also microbial growth, with both of these giving rise to emissions of volatile organic compounds (VOCs) that may contribute to indoor air health problems. The overall aim of this thesis was to investigate emissions of reactive and non-reactive VOCs from damp building materials and from the microorganisms growing on them, and also to investigate the possible health impact of these compounds. Three studies were carried out in order to study emissions of VOCs. The first investigated emissions from a mixture of five fungi (Aspergillus versicolor, Fusarium culmorum, Penicillium chrysogenum, Ulocladium botrytis and Wallemia sebi) and the second emissions from the bacterium Streptomyces albidoflavus. In both studies the microorganisms were cultivated on three different building materials (pine wood, particle board and gypsum board) and one synthetic media, MEA and TGEA respectively. The bacterium was also cultivated on sand. Air samples from the cultures were collected on six different adsorbents and chemosorbents to sample a wide range of compounds such as VOCs, aldehydes, amines and light-weight organic acids. The samples were analyzed with gas chromatography, high-pressure liquid chromatography and ion chromatography. Mass spectrometry was used for identification of the compounds. Alcohols and ketones were the predominant compound groups identified. The bacterial culture growing on TGEA emitted ammonia, methylamine, diethylamine and ethylamine. The third study dealt with secondary emissions collected from buildings with moisture and mould problems. Samples were taken when the materials were dry and also after they had been wet for a week. Most alcohols and ketones could be identified from the wet materials. Trimethylamine and triethylamine, were identified from sand contaminated by Bacillus. One study looked at the development of a method for analysis of primary and secondary amines with LC-MS/MS. A three-step process was developed, with the first step screening the samples for NIT derivatives with selected reaction monitoring, SRM. In the second step a precursor ion scan gave the [M+H]+ ion, and the last step involved fragmentation with a product ion scan. It was possible to separate and identify all the investigated amines, which showed that the method was both specific and selective and therefore well suited for the analysis of amines in complex environments. The last study comprised two exposure studies. In study 1 each participant took part in two exposure conditions, one with air from mouldy building materials and one with blank air for a 60 minute period. In study 2 each participant was exposed four times (for a period of 10 min) at random to air from mouldy building materials and blank air, with and without nose-clip. The participants rated air quality and symptoms before, during and after each exposure. Exposure to moderate VOC levels resulted in reports of perceived poor air quality, but no such results were received when exposing the participants to low VOC levels.
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| 6. |
- Claeson, Anna-Sara, 1974-, et al.
(författare)
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Volatile organic compounds (VOCs) emitted from materials collected from buildings affected by microorganisms
- 2007
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Ingår i: Journal of Environmental Monitoring. - : Royal Society of Chemistry. - 1464-0325 .- 1464-0333. ; 9:3, s. 240-245
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Tidskriftsartikel (refereegranskat)abstract
- In this study mould damaged materials, including carpet, concrete, gypsum board, insulation, plastic, sand and wood, from 20 different buildings with moisture problems were collected. To study emissions from these materials both conventional methods for sampling, such as collection on Tenax TA, were used as well as complementary methods for sampling a wider spectrum of compounds, such as more volatile VOCs, amines and aldehydes. Analysis was carried out using gas chromatography and high-performance liquid chromatography. Mass spectrometry was used for identification of compounds. Alcohols and ketones were almost exclusively emitted from the materials after they had been wet for a week. Acids were also emitted in large quantities from wet gypsum board and plastic. No primary or secondary amines could be identified, but two tertiary amines, trimethylamine and triethylamine, were emitted from sand contaminated by Bacillus. The most common moulds found were Penicillium and Aspergillus. A multivariate method (partial least squares, PLS) was used to investigate the emission patterns from the materials. Materials with bacterial growth had a different VOC profile to those with only mould growth.
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| 7. |
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| 8. |
- Andersson, Linus, 1979-, et al.
(författare)
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Chemical Intolerance Is Associated With Altered Response Bias, not Greater Sensory Sensitivity
- 2020
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Ingår i: i-Perception. - : Sage Publications. - 2041-6695. ; 11:6
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Tidskriftsartikel (refereegranskat)abstract
- Chemical intolerance is a surprisingly prevalent condition or affliction characterized by adverse reactions to low levels of chemical, often odorous stimulation. Sufferers often assume that their plight is due to an uncommon sensory acuteness, yet studies repeatedly fail to reveal altered detection thresholds. Here, we investigated whether self-reported chemical intolerance is associated with altered sensory sensitivity or response bias. The sensory acuity (sensitivity; A) and sensory decision rule (criterion; B) to n-butanol was assessed using the method of constant stimuli in 82 participants with different degrees of chemical intolerance (low to high). Higher self-reported chemical intolerance was associated with a lower criterion, but not with sensitivity.
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| 9. |
- Andersson, Linus, et al.
(författare)
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Chemosensory perception, symptoms and autonomic responses during chemical exposure in multiple chemical sensitivity
- 2016
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer. - 0340-0131 .- 1432-1246. ; 89:1, s. 79-88
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Multiple chemical sensitivity (MCS) is a prevalent medically unexplained symptom characterized by symptom reactions to everyday chemical exposure below hygienic thresholds. The aim of this study was to investigate the expressions of hyper-reactivity in MCS during whole-body exposure to low concentrations of the odorant n-butanol.Methods: We exposed 18 participants with MCS and 18 non-ill controls to a low concentration of the odorantn-butanol using an exposure chamber. The first 10 min constituted blank exposure, after which then-butanol concentration increased and reached a plateau at 11.5 mg/m3.Results: MCS participants, compared with controls, reported greater perceived odor intensities, more unpleasantness to the exposure and increasing symptoms over time. MCS participants also expressed higher pulse rate and lower pulse rate variability than controls did. No group differences were found for breathing rate or tonic electrodermal activity responses.Conclusions: We conclude that MCS sufferers differ from healthy controls in terms of autonomic responses, symptoms and chemosensory perception during chemical exposure.
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| 10. |
- Claeson, Anna-Sara, 1974-, et al.
(författare)
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A standardized protocol for comparable analysis of GSH/GSSG by UHPLC-ESI-MSMS for human plasma
- 2019
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Ingår i: Journal of chromatography. B. - : Elsevier. - 1570-0232 .- 1873-376X. ; 1104, s. 67-72
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Tidskriftsartikel (refereegranskat)abstract
- Variability in the levels of GSH and GSSG in plasma is suggested to derive from inadequate pre-processing methods. The aim of this study was to develop a protocol for comparable and reliable measurements of GSH/GSSG. Venous blood from 8 healthy individuals were collected and divided into 7 different pre-processing procedures. For three of the samples an extraction mixture was added after 0 (baseline), 4 and 8 min and for three of the samples the extraction mixture was added at different times during defrost. A worst case scenario where a sample was left in a cool box during 6 h was also included. The samples were analyzed with UHPLC-ESIMSMS. A large difference in the levels of GSH and GSSG were identified and it was clearly associated with the sample handling procedures. A sample left untreated for 4 min will have significantly reduced amount of GSH. Stability tests showed that the level of GSH was reduced after 3 months in -80 degrees C.
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