| 1. |
- Haga, Susanna Lohman, et al.
(författare)
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Personal exposure levels to O3, NOx and PM10 and the association to ambient levels in two Swedish cities.
- 2021
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Ingår i: Environmental monitoring and assessment. - : Springer Science and Business Media LLC. - 1573-2959 .- 0167-6369. ; 193:10
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Tidskriftsartikel (refereegranskat)abstract
- Exposure to air pollution is of great concern for public health although studies on the associations between exposure estimates and personal exposure are limited and somewhat inconsistent. The aim of this study was to quantify the associations between personal nitrogen oxides (NOx), ozone (O3) and particulate matter (PM10) exposure levels and ambient levels, and the impact of climate and time spent outdoors in two cities in Sweden. Subjects (n=65) from two Swedish cities participated in the study. The study protocol included personal exposure measurements at three occasions, or waves. Personal exposure measurements were performed for NOx and O3 for 24h and PM10 for 24h, and the participants kept an activity diary. Stationary monitoring stations provided hourly data of NOx, O3 and PM, as well as data on air temperature and relative humidity. Data were analysed using mixed linear models with the subject-id as a random effect and stationary exposure and covariates as fixed effects. Personal exposure levels of NOx, O3 and PM10 were significantly associated with levels measured at air pollution monitoring stations. The associations persisted after adjusting for temperature, relative humidity, city and wave, but the modelled estimates were slightly attenuated from 2.4% (95% CI 1.8-2.9) to 2.0% (0.97-2.94%) for NOx, from 3.7% (95% CI 3.1-4.4) to 2.1% (95% CI 1.1-2.9%) for O3 and from 2.6% (95% 0.9-4.2%) to 1.3% (95% CI-1.5-4.0) for PM10. After adding covariates, the degree of explanation offered by the model (coefficient of determination, or R2) did not change for NOx (0.64 to 0.63) but increased from 0.46 to 0.63 for O3, and from 0.38 to 0.43 for PM10. Personal exposure to NOx, O3 and PM has moderate to good association with levels measured at urban background sites. The results indicate that stationary measurements are valid as measure of exposure in environmental health risk assessments, especially if they can be refined using activity diaries and meteorological data. Approximately 50-70% of the variation of the personal exposure was explained by the stationary measurement, implying occurrence of misclassification in studies using more crude exposure metrics, potentially leading to underestimates of the effects of exposure to ambient air pollution.
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| 2. |
- Hagenbjörk-Gustavsson, Annika, et al.
(författare)
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Hälsorelaterad miljöövervakning. Cancerframkallande ämnen i tätortsluft : personlig exponering och bakgrundsmätningar i Umeå 2013
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Undersökningen kartlägger 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.Mätningarna upprepades på 20 personer. Utöver de personburna mätningarna genomfördes även stationära mätningar på två platser utomhus, samt för partiklar även inomhus hos 20 deltagare. Deltagarfrekvensen var 66% och medelåldern var 35 år. Den personliga medianhalten för bensen och 1,3-butadien var 1,4 μg/m3 respektive 0,2 μg/m3 vilket är något lägre än halterna år 2001. Bensenhalten överskrider lågrisknivån (1,3 μg/m3), medan halten 1,3-butadien ligger i nedre kanten av lågriskintervallet. Det fanns en signifikant korrelation mellan den personliga exponeringen för bensen och 1,3-butadien (rs=0.50, p=<0.01). Medianhalten för formaldehyd var 12 μg/m3, och halterna var högre bland de som bodde i villa jämfört med lägenhet. Medianhalten kvävedioxid var 12 μg/m3. PM2.5 mättes utomhus i urban bakgrund samt hemma hos deltagare under två dygn. Medianvärdet för inomhusmätningarna av PM2.5 var högre än motsvarande halt vid mätningarna 2007 (1,9 μg/m3). PM2,5 filtren analyserades även på sitt innehåll av polycykliska kolväten och halterna inomhus var lägre jämfört med halterna utomhus, och var klart lägre än den fastställda lågrisknivån.
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| 3. |
- Hagenbjörk-Gustavsson, Annika
(författare)
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Kväveoxid- och kvävedioxidhalter i Umeå : Sammanställning av mätningar gjorda med diffusionsprovtagare mellan november 2009 och december 2019
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Två veckomätningar (sommartid respektive vintertid) av kvävedioxid (NO2) och kväveoxider (NOx) har under 2019 utförts med diffusionsprovtagare på 41 platser i Umeå. Två veckomätningar har gjorts varje år på dessa platser sedan 2009 och totalt 21 mätningar har utförts på samma sätt över åren. Mätplatsernas geografiska läge kan ha varierat något över tid, provtagare har ibland plockats ned av förbipasserande, och det ha uppstått andra tekniska fel, varför alla mätplatser inte har maximalt antal mätningar. Det finns 23 respektive 24 mätplatser där mätningar har gjorts vid alla 21 tillfällen för NO2 respektive NOx.De högsta halterna har uppmätts på trafikerade platser under vinterhalvåret p.g.a. större utsläpp och stillastående luft, s.k. inversion. Vid mätningarna 2019 uppmättes de högsta halterna NO2 både sommartid och vintertid vid en husfasad belägen på Västra Esplanaden, centralt i Umeå (19 μg/m3 respektive 64 μg/m3). NOx-halten vintertid var högst vid samma mätpunkt på Västra Esplanaden (151 μg/m3) medan halten vid sommarmätningen var högst vid Östra Kyrkogatan, mittemot Navet (51 μg/m3).
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| 4. |
- Johansson, Elisabeth, et al.
(författare)
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Ozone air levels adjacent to a dental ozone gas delivery system
- 2007
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Ingår i: Acta Odontologica Scandinavica. - : Informa UK Limited. - 0001-6357 .- 1502-3850. ; 65:6, s. 324-330
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Tidskriftsartikel (refereegranskat)abstract
- Objective. Ozone (O(3)) has been suggested as an anti-microbial treatment in dentistry, with an ozone gas delivery system introduced for the treatment of fissure and root caries. The aim of this study was to investigate the sealing capacity of the novel delivery system and its re-suction capacity during accidental displacement of the cup at different stages of ozone delivery. Material and methods. Ozone leakage was studied in vitro after application on a flat metal surface and on buccal and occlusal tooth surfaces. An ozone analyzer was used to measure ozone gas concentrations adjacent to the delivering cups when adapted to the target surfaces during and after 10-20 s application cycles. The measured levels were compared with the background concentrations in the room. Measurements were performed 1) after complete ozone application cycles, 2) within the cycle before the start of the suction period, and 3) after displacements of the cup during the cycles. Results. Ozone air values varied between 8 and 166 microg.m(-3) for the flat metal surface and between 0 and 108 microg.m(-3) for the tooth surfaces. Ozone leakage levels were 7.6 microg.m(-3) for the flat and 7.4 microg.m(-3) and 5.6 microg.m(-3) for the buccal and occlusal surfaces, respectively, and 5.2 microg.m(-3) and 9.8 microg.m(-3) for the premolar and molar surfaces, respectively. Cycles with displacement showed significantly higher leakage levels than continuous complete cycles (p=0.03). Conclusions. Ozone application cycles with displacements showed significantly higher leakage levels than continuous complete cycles. The largest ozone delivery cups showed the highest leakage values. A change in background levels was seen with similar change in adjacent ozone levels. The overall measured ozone leakage values were low after normally functioning delivery cycles and after repeated displacements. The delivery system can be considered safe.
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| 5. |
- Orru, Hans, et al.
(författare)
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Exposures, Symptoms and Risk Perception among Office Workers in Relation to Nanoparticles in the Work Environment
- 2022
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Ingår i: International Journal of Environmental Research and Public Health. - : MDPI. - 1661-7827 .- 1660-4601. ; 19:10
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Tidskriftsartikel (refereegranskat)abstract
- Submicroscopic nanoparticles (NPs) in air have received much attention due to their possible effects on health and wellbeing. Adverse health impacts of air pollution may not only be associated with level of exposure, but also mediated by the perception of the pollution and by beliefs of the exposure being hazardous. The aim of this study was to test a model that describes interrelations between NP pollution, perceived air quality, health risk perception, stress, and sick building syndrome. In the NanoOffice study, the level of NPs was measured and a survey on health risk perception was conducted among 260 employees in twelve office buildings in northern Sweden. Path analyses were performed to test the validity of the model. The data refute the model proposing that the NP exposure level significantly influences stress, chronic diseases, or SBS symptoms. Instead, the perceived exposure influences the perceived risk of NP, and the effect of perceived exposure on SBS and chronic disease is mediated by stress. There was little concern about nanoparticles, despite relatively high levels in some facilities. Perceived pollution and health risk perception may explain a large part of the environmentally induced symptoms and diseases, particularly in relatively low levels of pollution. The research results raise important questions on the physiologically or psychologically mediated health effects of air pollution.
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| 6. |
- Orru, Hans, et al.
(författare)
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Indoor and outdoor nanoparticle concentrations in an urban background area in northern Sweden : The NanoOffice study
- 2021
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Ingår i: Environments. - : MDPI. - 2076-3298. ; 8:8
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, nanoparticles (NPs) have received much attention due to their very small size, high penetration capacity, and high toxicity. In urban environments, combustion-formed nanoparticles (CFNPs) dominate in particle number concentrations (PNCs), and exposure to those particles constitutes a risk to human health. Even though fine particles (<2.5 µm) are regularly monitored, information on NP concentrations, both indoors and outdoors, is still limited. In the NanoOffice study, concentrations of nanoparticles (10–300 nm) were measured both indoors and outdoors with a 5-min time resolution at twelve office buildings in Umeå. Measurements were taken during a one-week period in the heating season and a one-week period in the non-heating season. The measuring equipment SMPS 3938 was used for indoor measurements, and DISCmini was used for outdoor measurements. The NP concentrations were highest in offices close to a bus terminal and lowest in offices near a park. In addition, a temporal effect appeared, usually with higher concentrations of nanoparticles found during daytime in the urban background area, whereas considerably lower nanoparticle concentrations were often present during nighttime. Infiltration of nanoparticles from the outdoor air into the indoor air was also common. However, the indoor/outdoor ratios (I/O ratios) of NPs showed large variations between buildings, seasons, and time periods, with I/O ratios in the range of 0.06 to 0.59. The reasons for high indoor infiltration rates could be NP emissions from adjacent outdoor sources. We could also see particle growth since the indoor NPs were, on average, almost twice as large as the NPs measured outdoors. Despite relatively low concentrations of NPs in the urban background air during nighttime, they could rise to very high daytime concentrations due to local sources, and those particles also infiltrated the indoor air.
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