1. |
- Annika, Hagenbjörk-Gustafsson, et al.
(author)
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Spatial variation of ground level ozone and the relation between ozone and NO2/NOx in two Swedish cities
- 2013
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Conference paper (peer-reviewed)abstract
- Background Ozone is a pollutant known to cause adverse effects on human health. It is formed by reactions between nitrogen oxides (NOx) and hydrocarbons under the influence of sunlight. In urban areas ozone is consumed oxidating nitrogen oxide (NO) to nitrogen dioxide (NO2). Despite the potential to cause adverse health effects, the local spatial distribution of ozone and the relationship between ozone, NO2 and NOx in different environments is poorly studied.Aims Our aim was to study the concentrations and spatial distribution of ozone in two cities, Malmö in the south of Sweden and Umeå in the north of Sweden, since the contribution of ozone from other parts of Europe decreases with higher latitude. We also wanted to investigate differences in the ozone/NO2 and the ozone/NOx ratios between the cities and between different environments.Methods Ozone, NO2 and NOx concentrations were measured with Ogawa diffusive samplers during three one-week campaigns in April, May/June and in August 2012. Measurements were conducted simultaneously at 20 sites in each city outside preschools, distributed at traffic sites, urban background sites and regional background (rural) sites. Results The average concentration of ozone in Malmö and Umeå were 67,5 µg/m3 and 50,6 µg/m3, respectively. The mean ozone/NOx ratio was of equal magnitude in Malmö and in Umeå, and in both cities the ratio was highest at rural sites and lowest at traffic sites. In Umeå there was a clear trend with highest ozone concentrations at rural sites and lowest concentrations at traffic sites, a trend that was not as obvious in Malmö. In Umeå the ozone/NO2 ratio at rural sites was about three times larger compared to Malmö.Conclusions There is a clear local variation of ozone, with stronger gradients in northern (Umeå) Sweden in comparison to southern Sweden (Malmö). This can partly be explained by less long-range transport of ozone and larger impact of local NO emissions that reduce ozone in northern Sweden.
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2. |
- Cyrys, Josef, et al.
(author)
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Variation of NO2 and NOx concentrations between and within 36 European study areas : Results from the ESCAPE study
- 2012
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In: Atmospheric Environment. - : Elsevier BV. - 1352-2310 .- 1873-2844. ; 62, s. 374-390
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Journal article (peer-reviewed)abstract
- The ESCAPE study (European Study of Cohorts for Air Pollution Effects) investigates long-term effects of exposure to air pollution on human health in Europe. This paper documents the spatial variation of measured NO2 and NOx concentrations between and within 36 ESCAPE study areas across Europe.In all study areas NO2 and NOx were measured using standardized methods between October 2008 and April 2011. On average, 41 sites were selected per study area, including regional and urban background as well as street sites. The measurements were conducted in three different seasons, using Ogawa badges. Average concentrations for each site were calculated after adjustment for temporal variation using data obtained from a routine monitor background site.Substantial spatial variability was found in NO2 and NOx concentrations between and within study areas; 40% of the overall NO2 variance was attributable to the variability between study areas and 60% to variability within study areas. The corresponding values for NOx were 30% and 70%. The within-area spatial variability was mostly determined by differences between street and urban background concentrations. The street/urban background concentration ratio for NO2 varied between 1.09 and 3.16 across areas. The highest median concentrations were observed in Southern Europe, the lowest in Northern Europe.In conclusion, we found significant contrasts in annual average NO2 and NOx concentrations between and especially within 36 study areas across Europe. Epidemiological long-term studies should therefore consider different approaches for better characterization of the intra-urban contrasts, either by increasing of the number of monitors or by modelling.
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3. |
- Hagenbjörk-Gustafsson, Annika, et al.
(author)
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Cancerframkallande ämnen i tätortsluft : Personlig exponering och bakgrundsmätningar i Umeå 2007
- 2008
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Reports (other academic/artistic)abstract
- Allmänbefolkningens exponering för några cancerframkallande luftföroreningar undersöktes iUmeå under perioden 15 oktober till 18 december 2007. Studien som är en del iNaturvårdsverkets hälsorelaterade miljöövervakning, genomfördes som personburna 7-dygnsmätningar på 40 slumpvis utvalda personer boende i Umeå tätort. Mätningenupprepades på 20 personer. Under samma period gjordes stationära mätningar på två platser(bibliotekstaket och E4) i centrala Umeå. De personburna och stationära mätningarnaomfattade bensen, 1,3-butadien, formaldehyd och kvävedioxid och utfördes meddiffusionsprovtagare. Inomhus hos 20 personer gjordes även 2-dygnsmätningar av partiklar(PM2.5) och polycykliska aromatiska kolväten (PAH) parallellt med mätningar vid den urbanabakgrundsstationen (bibliotekstaket).Deltagarfrekvensen var 81 %, deltagarna tillbringade i medeltal 89 % av mätveckan inomhus.Tre av deltagarna var rökare och övriga deltagare hade begränsad exponeringstid för passivrökning. En deltagare hade yrkesmässig exponering för de undersökta ämnena.Det fanns en signifikant korrelation mellan halter av bensen och 1,3-butadien uppmättpersonburet, men för övriga ämnen sågs ingen korrelation. Rökning och boendeform hadeingen påverkan på exponeringen. Vid jämförelse med 2001 års mätning i Umeå har personligexponering för bensen och 1,3-butadien minskat signifikant, medan exponeringen ökat förkvävedioxid.Vid E4 fanns ett signifikant samband mellan bensen och 1,3-butadienhalter som intenoterades vid bibliotekstaket. Bensenhalterna ligger i nivå med 2001 års mätning vidutomhusstationerna, medan kvävedioxidhalterna minskat, om än inte signifikant. Vidbibliotekstaket har 1,3-butadien- och formaldehydhalterna minskat signifikant.För bensen och kvävedioxid var korrelationen hög och signifikant mellan den personligamedelexponeringen för varje mätvecka och halter mätt stationärt. Motsvarande korrelation förformaldehyd och 1,3-butadien var låg.På grund av låga halter PM2.5 och PAH vid inomhusmätningarna beslutades hösten 2008 atten upprepad mätning i vardagsrum hos de fem individer som hade lägst halt partiklar skullegenomföras. Partikelhalterna (PM2.5) var högre (median = 4,1 μg/m3) vid den upprepademätningen i jämförelse med den första mätomgången. Medianhalten bens(a)pyren var vid denupprepade mätningen 36 pg/m3, och även för övriga partikulära PAH var halterna högre.
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4. |
- Hagenbjörk-Gustafsson, Annika, et al.
(author)
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Determinants of personal exposure to some carcinogenic substances and nitrogen dioxide among the general population in five Swedish cities
- 2014
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In: Journal of Exposure Science and Environmental Epidemiology. - : Springer Science and Business Media LLC. - 1559-0631 .- 1559-064X. ; 24:4, s. 437-443
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Journal article (peer-reviewed)abstract
- Environmental levels of airborne carcinogenic and related substances are comparatively better known than individual exposure and its determinants. We report on a personal monitoring program involving five Swedish urban populations. The aim of the program was to investigate personal exposure to benzene, 1,3-butadiene, formaldehyde, and nitrogen dioxide (NO2). The measurements were performed among 40 inhabitants during seven consecutive days, in one urban area each year, during 2000-2008. The estimated population exposure levels were 1.95 mu g/m(3) for benzene, 0.56 mu g/m(3) for 1,3-butadiene, 19.4 mu g/m(3) for formaldehyde, and 14.1,mu g/m(3) for NO2. Statistical analysis using a mixed-effects model revealed that time spent in traffic and time outdoors contributed to benzene and 1,3- butadiene exposure. For benzene, refueling a car was an additional determinant influencing the exposure level. Smoking or environmental tobacco smoke were significant determinants of exposure to NO2, benzene, and 1, 3-butadiene. Those with a gas stove had higher NO2 exposure. Living in a single-family house increased the exposure to formaldehyde significantly. In a variance component model, the between-subject variance dominated for 1,3-butadiene and formaldehyde, whereas the between-city variance dominated for NO2. For benzene, the between-subject and between-cities variances were similar.
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5. |
- Hagenbjörk-Gustafsson, Annika, et al.
(author)
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Field validation of the Ogawa diffusive sampler for NO(2) and NO(x) in a cold climate
- 2010
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In: Journal of Environmental Monitoring. - : Royal Society of Chemistry. - 1464-0325 .- 1464-0333. ; 12:6, s. 1315-24
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Journal article (peer-reviewed)abstract
- A small-scale field trial in Umeå, Sweden with Ogawa samplers and a chemiluminescence instrument indicated that the NO(2) concentration was underestimated with respect to the reference monitor, if calculated according to the manufacturer's Ogawa sampling protocol. By co-locating Ogawa samplers and reference monitors at six sites in two Swedish cities, uptake rates were determined for NO(2) and NO(x) better applicable to the Swedish conditions and climate. The concentrations of NO(2) and NO(x) calculated according to the instruction manual of the sampler and using the field-determined uptake rates were compared with values derived from chemiluminescence monitors for each week over which samples were taken. When calculated according to the manufacturer's suggested protocol, the Ogawa sampler underestimated the NO(2) concentrations by 9.1% on average for all samples (N = 53), with respect to the reference monitor. In contrast, NO(x) concentrations were overestimated by a mean value of 15% for all samples (N = 45). By using the field determined uptake rates for the calculation of NO(2) and NO(x) a better estimation of the concentrations was obtained. The ratio between concentrations determined with the Ogawa samplers and chemiluminescence monitors was then 1.02 for all measurements of NO(2) and 1.00 for NO(x). Precision, expressed as the mean coefficient of variation, was 6.4% for six, 6-replicate measurements of NO(2) and 3.7% for five, 6-replicate measurements of NO(x).
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6. |
- Hagenbjörk-Gustafsson, Annika, et al.
(author)
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Hälsorelaterad miljöövervakning. Cancerframkallande ämnen i tätortsluft. Personlig exponering och bakgrundsmätningar i Umeå 2013
- 2014
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Reports (other academic/artistic)abstract
- Syftet med undersökningen är att kartlägga allmänbefolkningens exponering via luften för vissa cancerframkallande ämnen (bensen, 1,3-butadien, formaldehyd) och kvävedioxid .Undersökningen genomfördes i centrala Umeå under hösten 2013, och inkluderade totalt 40 slumpvis utvalda personer i åldrarna 20-50 år. Deltagarna fick bära provtagare för bensen, 1,3-butadien, formaldehyd och kvävedioxid under en vecka, och mätningarna upprepades sedan på hälften av deltagarna. I samband med de personburna mätningarna fick deltagarna även besvara en enkät och föra dagbok över hur mycket tid de vistats i olika miljöer. Utöver de personburna mätningarna genomfördes även stationära veckomätningar av motsvarande ämnen utomhus på två platser (en gatustation och en urban bakgrundsstation) i centrala Umeå.Vid den urbana bakgrundsstationen genomfördes även mätningar av fina partiklar (PM 2.5) under två dygn parallellt med motsvarande mätningar hemma hos 20 av deltagarna. PM 2.5 filtren analyserades även för polycykliska aromatiska kolväten.Deltagarfrekvensen var 66%, och av de 40 deltagarna var 22 kvinnor och 18 män. Medelåldern var 35 år, endast 2 personer angav att de rökte och majoriteten bodde i lägenhet (68%). Största delen av tiden tillbringade deltagarna inomhus (90%) och endast en mindre del (ca 5%) i trafikerade miljöer.Resultaten av mätningarna presenteras i tabellen nedan. Den personliga medianhalten för bensen var något över den föreslagna lågrisknivån (1,3 μg/m 3) men något lägre jämfört med motsvarande mätningar i Umeå från 2001. Halten 1,3-butadien var lägre jämfört med tidigare mätomgångar och i nederkant av det intervall som utgör lågrisknivå (0,2-1,0 μg/m 3). Det fanns en signifikant korrelation mellan den personliga exponeringen för bensen och 1,3-butadien (rs=0.50, p=<0.01). Deltagare som bodde i villa hade högre formaldehydhalt jämfört med de som bodde i lägenhet. Medianhalten var något lägre jämfört med mätningarna 2001 och i samma storleksordning som vid mätningarna 2007. Medianhalten kvävedioxid var även den något högre jämfört med motsvarande halt uppmätt 2001 (8 μg/m 3), men i storleksordning som halten från mätningarna 2007 (11 μg/m 3). Ingen signifikant skillnad i halter kunde påvisas mellan män och kvinnor.De stationära mätningarna genomfördes vid kommunens urbana bakgrundsstation (bibliotekstaket) samt vid gatustationen Västra Esplanaden som veckomätningar, samt hemma hos 20 deltagare under två dygn (PM 2.5 och PAH). Medianhalt av bensen vid gatustationen 6 var lägre jämfört med tidigare år (1,6 μg/m 3 2001, 1,5 μg/m3 2007) medan halten uppmätt i urban bakgrund var något högre än tidigare år. För 1,3-butadien var halten vid gatustationen lägre jämfört med föregående år och lägre än motsvarande halt i urban bakgrund.Kvävedioxidhalten vid gatustationen låg i medeltal över 40 μg/m 3 vilket är den rådande miljökvalitetsnormen för årsmedelhalten (SFS 2010:477). Formaldehyd uppvisade ungefär samma mönster som vid tidigare mätningar med jämförbara halter i gatunivå och urban bakgrund. Median halten var högre än 2007.PM 2.5 mättes utomhus i urban bakgrund samt hemma hos 20 av deltagarna under två dygn. Medianvärdet för inomhusmätningarna av PM 2.5 var högre än motsvarande halt vidmätningarna 2007 (1,9 μg/m 3), medan medianhalten utomhus var lägre än vid 2007 års mätning. PM 2,5 filtren analyserades även på sitt innehåll av polycykliska kolväten, som i tabellen representeras av bens(a)pyren, och resultaten visade på betydligt högre halter i luften utomhus jämfört med inomhus. Halterna understiger väl den lågrisknivå som fastställts av institutet för miljömedicin (IMM) och Världshälsoorganisationen (WHO) på 100 pg/m 3. Man bör dock beakta att halterna inte inkluderar partiklar större än 2,5 μm i diameter.
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9. |
- Hagenbjörk-Gustafsson, Annika, 1956-, et al.
(author)
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Validation of a diffusive sampler for NO2
- 1999
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In: Journal of Environmental Monitoring. - : Royal Society of Chemistry. - 1464-0325 .- 1464-0333. ; 1, s. 349-352
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Journal article (peer-reviewed)abstract
- A diffusive sampler for NO2, Willems badge, was validated in laboratory experiments and field tests. The collecting reagent for NO2 in the sampler is triethanolamine, and the analysis is based on a modified colorimetric method, theSaltzman method. The analysis was performed by a flow injection analysis (FIA) technique. The sampling rate for the sampler was determined to be 40.0 ml min−1. There was no effect of NO2 concentration or relative humidity on sampling rate, and the influence of sampling time was found to be small. The detection limit was 4 mg m−3 for a 24 hsample. The capacity is high enough to allow sampling of 150 mg m−3 for 7 days, which is twice the recommended Swedish short-term (24 h) guideline value as a 98-percentile over 6 months. In field tests, the sampler performedwell, even at wind speeds higher than 2 m s−1, and at low temperatures. The overall uncertainty of the method was 24%. The sensitivity and capacity of the method also make it suitable for personal sampling for 2–8 h in working environments.
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10. |
- Hagenbjörk-Gustafsson, Annika, 1956-
(author)
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Validation of diffusive samplers for nitrogen oxides and applications in various environments
- 2014
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Doctoral thesis (other academic/artistic)abstract
- The overall aim of this thesis was to validate diffusive samplers for measurements of nitrogen dioxide (NO2) and nitrogen oxides (NOx). The Willems badge was validated for NO2 measurements both in laboratory tests and in field tests (Paper I-II). The sampling rate was 40.0 mL/min for ambient air concentrations and 46.0 mL/min for higher concentrations. No effects of different factors on sampling rate were found except for a reduced sampling rate at low wind velocity. The results of the laboratory validation were confirmed in field tests in ambient air and with personal sampling. The correlation between diffusive samplers and the reference monitor was good for ambient measurements. In conclusion, the Willems badge performs well at wind velocities down to 0.3 m/s, and this makes it suitable for personal sampling but less suitable for measurements in indoor air where the wind velocity is lower. Paper III reports about the field validation of the Ogawa diffusive samplers. Absolute humidity and temperature were found to have the strongest effect on sampling rate with lower uptake rates at low absolute humidity or temperature. The sampling rates above 0 °C were 8.6 mL/min for NO2 and 9.9 mL/min for NOx. NO2 and NOx concentrations that were determined using the manufacturer’s protocol were either underestimated or overestimated. The agreement between concentrations measured by the Ogawa sampler and the reference monitor was improved when field-determined sampling rates were used to calculate concentrations. Paper IV is based on a study with the aim of assessing the exposure of the Swedish general population to NO2 and some carcinogenic substances. The surveys were performed in one of five Swedish cities every year. In each survey, personal measurements of NO2 and some carcinogenic substances were conducted on 40 randomly selected individuals. In the study presented in this thesis, the NO2 part of the study is in focus and results were available for eight surveys conducted across the five cities. The estimated arithmetic mean concentration for the general Swedish population was 14.1 μg/m3. The exposure level for NO2 was higher for smokers compared with non-smokers, and the NO2 exposure levels were higher for people who had gas stoves at home or who were exposed at their workplace. The exposure was lower for those who had oil heating in their houses.
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