| 1. |
- Fjällström, Pär, et al.
(author)
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Drying of linseed oil paints: a laboratory study of aldehyde emissions
- 2002
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In: Industrial Crops and Products. ; 16:3, s. 173-84
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Journal article (peer-reviewed)abstract
- The effects of temperature, air humidity, air exchange rate, artificial light and fatty acid constitution on the emissions of aldehydes from linseed oil paint were investigated. Experiments were designed using a multivariate approach and data were analysed using different projection methods (principal component analysis, partial least-squares). Paints used were produced out of two different types of oils, where the fatty acid chains were either mainly linoleic or linolenic acid. The paints were applied onto glass plates and dried in chambers with a controlled climate. Aldehydes were sampled using silica gel impregnated with 2,4-dinitrophenylhydrazine and analysed by HPLC with UV and MS detection. Consecutive sampling of aldehydes every eighth hour as well as total aldehyde sampling was performed during the first 5 days after application of the paints. Hexanal and propanal were the dominating aldehydes emitted for linoleic and linolenic acid rich paint, respectively. Temperature and humidity sped up the emission process, giving a higher total amount of aldehydes. A higher amount of linoleic acid slowed down the emission process and gave higher total amounts of aldehydes. Artificial light and air exchange rate showed no significant effects on the emission process.
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| 2. |
- Magnusson, R, et al.
(author)
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Determination of chemical composition and mutagenicity in particles from chainsaw exhaust. Experimental set-up, stability and results from two different fuels
- 2000
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In: Environmental Technology. - 0959-3330. ; 21:7, s. 819-29
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Journal article (peer-reviewed)abstract
- A dilution tunnel for sampling of particles and gaseous emissions in chainsaw exhaust was constructed and tested for reproducibility. In addition the equipment was used to measure chainsaw emissions when using two different fuels, aliphatic petrol with synthetic lubricating oil and regular lead-free petrol with mineral lubricating oil. The content of polycyclic aromatic hydrocarbons (PAH) and the mutagenicity of sampled particles were measured as well as the concentration of carbon monoxide (CO), nitrogen oxides (NOx) and aldehydes in the exhaust. particles were sampled isokinetically and collected on a filter followed by two polyurethane foam plugs (PUF) in series for sampling of the semivolatile components. PAH were analysed by a coupled liquid chromatography - gas chromatography (LC-GC) system and mutagenicity testing was carried out by using Ames Salmonella assay. The measured physical parameters as well as the particulate, semivolatile and gaseous emissions showed that reproducible measurements of exhaust emissions could be achieved using this experimental set-up. In terms of mutagenicity when testing for reproducibility, a small but significant effect was observed for the Salmonella strains TA98 and TA100 in the absence of a metabolizing system, both for the particulate phase and the semivolatile components. A significant difference was seen between the two different fuels tested, the conventional petrol with mineral oil having 5-10 times higher concentrations of different PAH compounds and a much higher mutagenic effect for all strains. This difference was seen both for the particulate phase and the semivolatile components.
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| 3. |
- Magnusson, Roger, et al.
(author)
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Effect of Gasoline and Lubricant on Emissions and Mutagenicity of Particles and Semivolatiles in Chain Saw Exhaust
- 2000
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In: Environmental Science & Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 34:14, s. 2918-24
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Journal article (peer-reviewed)abstract
- The exhaust from a two-stroke chain saw engine was characterized using two different types of gasoline, aliphatic gasoline and conventional lead-free gasoline, in combination with four lubricants differing in mineral oil, polyolester, and polyisobutylene (PIB) content. This characterization was focused on emissions of polycyclic aromatic hydrocarbons (PAH) and mutagenicity testing using Ames Salmonella assay. In addition, exhaust emissions of carbon monoxide (CO), nitrogen oxides (NOx), aldehydes, and hydrocarbons (HC) were measured. The two-stroke engine was tested in a test bench, and particulate, semivolatile, and gaseous exhaust components were sampled using a dilution tunnel. Much less PAH were emitted when using aliphatic gasoline due to a much lower gasoline content of PAH and aromatics than the conventional gasoline. Also about half the NOx emissions, up to 50% higher formaldehyde and acetaldehyde emissions, and 10% higher total HC emissions were observed for the aliphatic gasoline. The influence of lubricant on the studied exhaust emissions was found to be of minor importance. In terms of mutagenicity, significant effects were seen for six of the eight gasoline/lubricant combinations, and the highest effects were observed without a metabolizing system. Generally, the conventional gasoline gave higher effects than did the aliphatic gasoline. A difference between lubricants was also seen, especially in combination with gasoline A; however, the interpretation of mutagenic effects of the lubricants was not straightforward. Overall, one synthetic ester-based lubricant and one mineral oil-based lubricant gave the highest mutagenicity.
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| 4. |
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| 5. |
- Almroth, Gabriel, 1953-, et al.
(author)
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Perspectives on hepatitis B infections and the efficacy of vaccination (hepatitis B and pneumococci) in dialysis patients.
- 2003
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In: Upsala journal of medical sciences. - : Uppsala Medical Society. - 0300-9734 .- 2000-1967. ; 108:1, s. 61-74
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Journal article (peer-reviewed)abstract
- Hepatitis B is a well known problem in dialysis units. We therefore examined the historical frequency of hepatitis B carriers in our unit, our vaccination program to hepatitis B virus (HBV), the response to hepatitis B vaccine, the IgG subclass response of anti-HBs and the response and IgG subclass response to pneumococcal vaccination (another vaccine) in dialysis patients. From 1970 and onwards 23 HBV carriers were found, but no new cases of hepatitis B occurred during the study period, i.e. from 1980 and onwards. Only one of the carriers was alive by the end of 2001. In four patients liver disease (in one of them liver cirrhosis) may have been a concomitant cause of death. The antibody response to hepatitis B vaccine was significantly lower in patients than in staff. In four patients a fourth injection was cancelled due to transplantation and bad health, while such data were lacking in 8 cases. In anti-HBs positive patients and controls a significant difference in the response of healthy adults was observed in anti-HBs IgG1 (p < 0.001) vs all other IgG subclasses. Dialysis patients had low levels, or negative findings, in all cases, with IgG1 as the highest proportion found (3/11 patients). An antibody response to pneumococcal vaccination was registered in 25 out of 29 dialysis patients (in all 86%). The IgG-subclass vaccination response to pneumococci in 28 dialysis patients was mainly IgG2 and IgG1 but also occurred in IgG3 and IgG4. Prevaccination antibody levels of the controls were higher in IgG1 and IgG2 (p < 0.01) (n = 21) than in dialysis patients (n = 28). Hepatitis B is nowadays a rare, but still dangerous disease in nephrology units. Dialysis patients have a reduced response to hepatitis B vaccine and vaccination schedules should be started early as some patients otherwise may not receive a fourth injection. The adequate antibody response to pneumococcal vaccination mainly due to IgG2 and IgG1 antibodies indicates that the antigen involved is important in vaccination responses in dialysis patients.
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| 6. |
- Fick, Jerker, et al.
(author)
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A study of the gas-phase ozonolysis of terpenes: the impact of radicals formed during the reaction
- 2002
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In: Atmospheric Environment. - 1352-2310 .- 1873-2844. ; 36:20, s. 3299-3308
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Journal article (peer-reviewed)abstract
- The gas-phase ozonolysis of α-pinene, Δ3-carene and limonene was investigated at ppb levels and the impact of the ozone, relative air humidity (RH), and time was studied using experimental design. The amounts of terpene reacted varied in the different settings and were as high as 8.1% for α-pinene, 10.9% forΔ3-carene and 23.4% for limonene. The designs were able to describe almost all the variation in the experimental data and were also successful in predicting omitted values. The results described the effects of time and ozone and also showed that RH did not have a statistically significant effect on the ozonolysis. The results also showed that all three terpenes were affected by an additional oxidation of OH radicals and/or other reactive species. The results from the designs states that this additional oxidation was responsible for 40% of the total amount of α-pinene reacted, 33% of the total amount of Δ3-carene reacted and 41% of the total amount of limonene reacted at the settings 20 ppb terpene, 75 ppb ozone, 20% RH and a reaction time of 213 s. Additional experiments with 2-butanol as OH radical scavenger showed that the reaction with OH radicals was responsible for 37% of the total α-pinene reacted and 39% of the total Δ3-carene reacted at the same settings. The scavenger experiments also showed that there were no significant amounts of OH radicals formed during the ozonolysis of limonene. The results from the designs were also compared to a mathematical model in order to evaluate further the data.
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| 7. |
- Fick, Jerker, 1971-
(author)
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Chemical reactions in ventilation systems : Ozonolysis of monoterpenes
- 2003
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Doctoral thesis (other academic/artistic)abstract
- Chemicals in indoor air, either emitted from a source or from a reaction, have been suggested to cause ill health in buildings. However, no clear correlations between exposure and health effects have been made. In this thesis we studied the reaction between monoterpenes, a group of biogenic unsaturated C10 hydrocarbons, and ozone. Ozonolysis of monoterpenes was used as model reactions for unsaturated compounds in ambient air. Also the products formed from these reactions have been suggested as important participants in the occurrence of discomfort and ill health in buildings. To enable a reliable and sensitive measurement of ppb-ppt levels of monoterpenes and the formed products in the presence of ozone an evaluation of available scrubber materials was made. Potassium iodide was shown to remove ambient levels of ozone and have a recovery of >95% for all monoterpenes and formed products included in the investigation. Experimental conditions showed to have a large impact on the initial steps of the ozonolysis, and also on the composition of the formed products. We showed that water plays an important and complex role both in the initial stage of ozonolysis of ∆3-carene and in the formation and composition of products from the ozonolysis of ∆-pinene. The use of experimental design facilitated the evaluation of the investigated reactions. We showed that the formation of OH radicals could be studied using multiple linear regression models and that the presence or absence of OH radicals had a profound impact on the formation of many of the formed products. We also made an observation of the lack of formed OH radicals in the ozonolysis of limonene and discussed probable causes of this observation. Despite the short reaction times and the ambient levels of ozone and monoterpenes used in our experiments we showed that a number of oxidation products were formed, and that the reaction rate is significantly increased in a ventilation system. This formation is underestimated by theoretical calculations and leads to high amounts of known irritants in the indoor air. We showed that theoretical calculations underestimate the formation of these oxidation products 3-13 times, depending on ventilation system and monoterpene.
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| 8. |
- Fick, Jerker, et al.
(author)
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Effect of OH radicals, relative humidity, and time on the composition of the products formed in the ozonolysis of α-pinene
- 2003
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In: Atmospheric Environment. ; 37:29, s. 4087-96
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Journal article (peer-reviewed)abstract
- The gas-phase ozonolysis of α-pinene at ppb levels were studied and the effects of OH radicals formed in the reaction, the relative humidity (RH), and time on the products formed were investigated. Identified products were pinic acid, glyoxal, methyl glyoxal, norpinonic acid and a norpinonic acid isomer, pinonic acid, a C4 dicarbonyl, a C5 dicarbonyl, norpinon aldehyde, and pinon aldehyde. The different parameters effect on the formation of these products were evaluated using experimental design and multivariate modeling. Pinonic acid, norpinonic acid and its isomer, were not detected in the absence of OH radicals. The amounts of pinic acid, norpinon aldehyde, and pinon aldehyde all decreased in the absence of OH radicals. Glyoxal and methyl glyoxal were not affected.The formation of pinonic acid decreased when the RH was increased. The formation of pinic acid, glyoxal, methyl glyoxal, and pinon aldehyde increased with increasing RH, while norpinon aldehyde was not affected. The implications of these observations and additional interaction effects are discussed, and a novel route of the formation of pinic acid is presented.
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| 9. |
- Fick, Jerker, et al.
(author)
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Formation of oxidation products in a ventilation system
- 2004
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In: Atmospheric Environment. - : Elsevier BV. - 1352-2310. ; 38:35, s. 5895-9
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Journal article (peer-reviewed)abstract
- We have studied the formation of oxidation products from the ozonolysis of a monoterpene (α-pinene) in an authentic ventilation system. We observed ten products, norpinic acid, pinic acid, glyoxal, methyl glyoxal, norpinonic acid, pinonic acid, a C4 dicarbonyl (C4H6O2), a C5 dicarbonyl (C5H8O2), norpinon aldehyde, and pinon aldehyde. Experiments were conducted at a low (2.0 g m−3) and moderate (8 g m−3) humidity levels. All products but C4 dicarbonyl and norpinon aldehyde were detected at the low humidity level, but only glyoxal, methyl glyoxal, C4 dicarbonyl, norpinon aldehyde and pinon aldehyde were detected at a moderate humidity. Experiments were conducted at low ppb levels (75 ppb ozone and 4 and 10 ppb α-pinene) and with a short reaction time (75 s). Experiments showed that 5–6% of the α-pinene reacted, which was approximately 4–5 times more than predicted by theoretical calculations. This discrepancy suggests a significant contribution from heterogeneous reactions. These oxidation products were formed despite low reactant concentrations and a short reaction time, indicating that the formation of oxidation products likely occurs at ambient levels and in real settings.
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| 10. |
- Fick, Jerker, et al.
(author)
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Ozone Removal in the Sampling of Parts per Billion Levels of Terpenoid Compounds: An Evaluation of Different Scrubber Materials
- 2001
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In: Environmental Science & Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 35:7, s. 1458-62
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Journal article (peer-reviewed)abstract
- Some reactive volatile organic compounds (VOCs) are prone to degradation during sampling in an ozone-rich environment. A wide variety of different chemicals have been used to remove the ozone prior to sampling, but the possibility of interference by such chemicals with the sampled VOCs has not been thoroughly examined. In the present investigation, the retention/degradation of four terpenes (-pinene, -pinene, 3-carene, and limonene) and isoprene together with some of their oxidation products (-pinene oxide, nopinone, 4-acetyl-1-methylcyclohexene (AMCH), methylglyoxal, and methacrolein) has been studied, using various ozone-removing chemicals in an attempt to evaluate their potential as ozone scrubbers in the sampling of ambient air. The chemicals included in this first screening and their ozone-removing capacity are as follows: KI, MnO2, and Na2SO3 removed ozone for more than 24 h when exposed to 73-78 ppb (150-160 g/m3) at a sampling flow rate of 500 mL/min. Silanized poly(1,4-phenylene sulfide) (PFS) removed ozone for 5 h, unsilanized PFS removed ozone for 1 h and 50 min, and Na2S2O3 removed ozone for 20 min. The recovery of the selected compounds with the different scrubbers was >95% for all compounds for KI; >95% for the terpenes oxidation products; >90% for the terpenes and isoprene for PFS; >90% for the terpenes and isoprene for MnO2 on copper nets, Na2SO3, and Na2S2O3; and <90% for the terpenes and isoprene for carulite (a commercial mixture between MnO2, CuO, and Al2O3), CuO, and indigo carmine.
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