| 1. |
- Bloom, Erica, et al.
(författare)
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Molds and mycotoxins in dust from water-damaged homes in New Orleans after hurricane Katrina
- 2009
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 19:2, s. 153-158
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Tidskriftsartikel (refereegranskat)abstract
- Dust collected in New Orleans homes mold-contaminated because of the flooding after hurricane Katrina was analyzed for molds and mycotoxins. The mycoflora was studied by cultivation and quantitative PCR for selected molds. The most commonly found mold taxa were Aspergillus, Cladosporium, and Penicillium. Verrucarol, a hydrolysis product of macrocyclic trichothecenes predominately produced by Stachybotrys spp. was identified in three dust samples by gas chromatography-tandem mass spectrometry, and sterigmatocystin (produced by various Aspergillus spp.) was found in two samples by high pressure liquid chromatography-tandem mass spectrometry. This is the first demonstration of mycotoxins in Katrina-associated dust samples. The analytical methods used represent valuable tools in further studies on bioaerosol exposure and health risks.
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| 2. |
- Afshari, A, et al.
(författare)
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Characterization of indoor sources of fine and ultrafine particles: a study conducted in a full scale chamber
- 2005
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Ingår i: Indoor Air. - : Hindawi Limited. - 1600-0668 .- 0905-6947. ; 15:2, s. 141-150
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Tidskriftsartikel (refereegranskat)abstract
- Humans and their activities are known to generate considerable amounts of particulate matter indoors. Some of the activities are cooking, smoking and cleaning. In this study 13 different particle sources were for the first time examined in a 32 m3 full-scale chamber with an air change rate of 1.7 ± 0.1/h. Two different instruments, a condensation particle counter (CPC) and an optical particle counter (OPC) were used to quantitatively determine ultrafine and fine particle emissions, respectively. The CPC measures particles from 0.02 μm to larger than 1.0 μm. The OPC was adjusted to measure particle concentrations in eight fractions between 0.3 and 1.0 μm. The sources were cigarette side-stream smoke, pure wax candles, scented candles, a vacuum cleaner, an air-freshener spray, a flat iron (with and without steam) on a cotton sheet, electric radiators, an electric stove, a gas stove, and frying meat. The cigarette burning, frying meat, air freshener spray and gas stove showed a particle size distribution that changed over time towards larger particles. In most of the experiments the maximum concentration was reached within a few minutes. Typically, the increase of the particle concentration immediately after activation of the source was more rapid than the decay of the concentration observed after deactivation of the source. The highest observed concentration of ultrafine particles was approximately 241,000 particles/cm 3 and originated from the combustion of pure wax candles. The weakest generation of ultrafine particles (1.17 × 107 particles per second) was observed when ironing without steam on a cotton sheet, which resulted in a concentration of 550 particles/cm3 in the chamber air. The highest generation rate (1.47 × 1010 particles per second) was observed in the radiator test.
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| 3. |
- Bornehag, CG, et al.
(författare)
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Dampness in buildings as a risk factor for health effects, EUROEXPO: a multidisciplinary review of the literature (1998-2000) on dampness and mite exposure in buildings and health effects
- 2004
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 14:4, s. 243-257
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Forskningsöversikt (refereegranskat)abstract
- The scientific literature on health effects from dampness in buildings, including mite exposure over the period 1998-2000 has been reviewed by a European group (EUROEXPO) of eight scientists in experience from medicine, epidemiology, toxicology and engineering. Forty studies deemed relevant have been the foundation for the conclusions. Dampness in buildings is a risk factor for health effects among atopics and non-atopics both in domestic and in public environments. However, the literature is not conclusive in respect of causative agents, e.g. mites, microbiological agents and organic chemicals from degraded building materials. There is a strong need for more multidisciplinary studies including expertise from all relevant areas. A general conclusion from the work was that there is a strong need for multidisciplinary reviews in scientific journals of articles dealing with associations between indoor environmental factors and health effects.
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| 4. |
- Carlstedt, F., et al.
(författare)
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PVC flooring is related to human uptake of phthalates in infants
- 2013
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 23:1, s. 32-39
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Tidskriftsartikel (refereegranskat)abstract
- Polyvinyl chloride (PVC) flooring material contains phthalates, and it has been shown that such materials are important sources for phthalates in indoor dust. Phthalates are suspected endocrine-disrupting chemicals (EDCs). Consecutive infants between 2 and 6 months old and their mothers were invited. A questionnaire about indoor environmental factors and family lifestyle was used. Urinary metabolites of the phthalates diethyl phthalate (DEP), dibutyl phthalate (DBP), butylbenzyl phthalate (BBzP), and dietylhexyl phthalate (DEHP) were measured in the urine of the children. Of 209 invited children, 110 (52%) participated. Urine samples were obtained from 83 of these. Urine levels of the BBzP metabolite monobenzyl phthalate (MBzP) was significantly higher in infants with PVC flooring in their bedrooms (P < 0.007) and related to the body area of the infant. Levels of the DEHP metabolites MEHHP (P < 0.01) and MEOHP (P < 0.04) were higher in the 2-month-old infants who were not exclusively breast-fed when compared with breast-fed children. The findings indicate that the use of soft PVC as flooring material may increase the human uptake of phthalates in infants. Urinary levels of phthalate metabolites during early life are associated with the use of PVC flooring in the bedroom, body area, and the use of infant formula. Practical Implications This study shows that the uptake of phthalates is not only related to oral uptake from, for example, food but also to environmental factors such as building materials. This new information should be considered when designing indoor environment, especially for children.
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| 5. |
- Holmér, Ingvar
(författare)
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Cold but comfortable? Application of comfort criteria to cold environments
- 2004
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 14:s7, s. 27-31
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Tidskriftsartikel (refereegranskat)abstract
- Fanger defined two physiological criteria that are basic requirements for people's perception of thermal neutrality and, eventually, thermal comfort. Mean skin temperature and evaporative heat loss are defined as functions of metabolic rate. The equations are derived from experiments in light clothing at or close to normal indoor climate. Relations between skin temperature and sweating on the one hand and thermal sensation and comfort on the other are well recognized; the precise description of the relationships vary and may differ from normal indoor environments to more extreme thermal stress. In moderately cold environments (around +10degreesC) ISO/DIS 7730 and ISO/DIS 11079 prescribe significantly different responses. Evaluation of the rationale behind the comfort criteria and the basic heat transfer equations in the two models reveals some clear differences. By modification of the sweating criteria and some of the heat transfer equations, predictions become much more similar. It is concluded that the basic comfort criteria may apply also to moderately cold and cold environments, but must consider the complex heat transfer through multilayer clothing in a more adequate way.
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| 6. |
- Larsson, Lennart, et al.
(författare)
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Tobacco smoking increases dramatically air concentrations of endotoxin.
- 2004
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 14:6, s. 421-424
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Tidskriftsartikel (refereegranskat)abstract
- We used a mass spectrometry-based assay for identifying the endotoxin (lipopolysaccharide, LPS) marker (R)-3-hydroxytetradecanoic acid in cigarette smoke particles and found that smoking involved inhalation of 17.4 pmol of endotoxin per each smoked cigarette. Indoor exposure to environmental tobacco smoke (ETS) entailed inhalation of 12.1 pmol of LPS/m3 air, an amount that was 120 times higher than the levels found in smoke-free indoor air. Endotoxin is one of the most potent inflammatory agents known, hence our results may help to explain the high prevalence of respiratory disorders among smokers, and they may also draw attention to a hitherto unknown or neglected risk factor of ETS.
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| 7. |
- Nilsson, Anders, et al.
(författare)
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Microorganisms and volatile organic compounds in airborne dust from damp residences
- 2004
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Ingår i: Indoor Air. International Journal of Indoor Environment and Health. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 14:2, s. 74-82
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Tidskriftsartikel (refereegranskat)abstract
- Airborne dust samples from damp (n = 9) and control (n = 9) residences were analyzed for microorganisms (molds and bacteria), bacterial markers (3-hydroxy fatty acids and muramic acid), and adsorbed volatile organic compounds (VOCs). The number of mold species was greater in the damp residences than in the controls (23 vs.18) and nine mold species were found only in damp residences. The levels of 3-hydroxy fatty acids and muramic acid correlated better in damp residences than in controls, indicating that damp conditions affect the bacterial flora of airborne dust. Identifications made by culture and microscopy of the major molds found, i.e. Aspergillus, Cladosporium, and Penicillum, coincided with the identification of VOCs known to be produced by these species. A number of additional VOCs irritating to the skin, eyes, or respiratory tract were also found. The results from this pilot study illustrate the diversity of microorganisms and VOCs present in the indoor environment and suggest that analysis of airborne dust may help to assess human exposure to microorganisms and chemical compounds.
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| 8. |
- Schneider, T, et al.
(författare)
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Airborne particle deposition onto the ocular surface
- 2005
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 15:3, s. 215-219
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Tidskriftsartikel (refereegranskat)abstract
- Eye irritation is one of the most frequently reported symptoms in relation to working in office-like environments. So far, no consistent association has been found between concentration of airborne particles and prevalence of eye irritation. External physical factors not hitherto considered could have a large influence on particle deposition velocity onto the ocular surface. This may have obscured the role airborne particles play. Based on previously published semi-empirical models, the paper describes the influence of turbulence, gravitational settling, electrical fields, and thermophoresis on deposition velocity. A probabilistic approach was used to determine percentile ranges in deposition velocity when the magnitude of these parameters varied within typical ranges. The calculations suggest that differences in external factors other than particle size may cause differences in the deposition velocity of one order of magnitude or more. Studies trying to find associations between airborne particle concentration levels and eye irritation should take into consideration the influence of external physical factors on deposition velocity.
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| 9. |
- Sebastian, Aleksandra, et al.
(författare)
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Characterization of the microbial community in indoor environments by chemical marker analysis: an update and critical evaluation.
- 2005
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 15 Suppl 9:9, s. 20-26
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Tidskriftsartikel (refereegranskat)abstract
- We published recently an integrated procedure for applying chemical marker analysis to characterize the microbiology of indoor environments comprising a scheme for extraction and analysis of markers of endotoxin, peptidoglycan/bacterial biomass, and fungal biomass. In the present paper, we report some significant improvements and also new possibilities of the described approach. We found that while 3-hydroxy fatty acids (3-OH FAs) of 10-14 carbon chain lengths are useful endotoxin markers, longer 3-OH FAs (i.e. with 16 carbon atoms and more) may rather serve as markers of Actinobacteria. We introduced C-13-labeled 3-hydroxytridecanoic acid, from labeled Pectinatus cerevisiiphilus, as an internal standard to improve quantification of the 3-OH FAs in the gas chromatography-mass spectrometry analysis. Finally, in experiments aiming to identify a suitable method for collection of house dust for chemical marker analysis, we found that the marker compositions of dusts sedimented on plexiglass plates that were spatially well-distributed in a studied room at different heights above floor level, were undistinguishable. This type of sampling thus appears to be well suited for use, e.g. in epidemiological studies. In summary, the presented work describes important new capabilities of chemical marker analysis in defining human exposure to microorganisms in indoor environments.
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| 10. |
- Sjöberg, Anders, et al.
(författare)
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An experimental parametric study of VOC from flooring systems exposed to alkaline solutions
- 2007
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Ingår i: Indoor Air. - : Hindawi Limited. - 1600-0668 .- 0905-6947. ; 17:6, s. 450-457
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Tidskriftsartikel (refereegranskat)abstract
- This study outlined the influence of a number of parameters affecting the emission rate from one of the largest sources of VOC in the building stock in the Nordic countries. This source is flooring systems of polyvinyl chloride or linoleum attached to a substrate of moisture damaged or insufficiently dried concrete. The secondary emission rate of degradation products was measured, with the Field and Laboratory Emission Cell, on different flooring systems consisting of three different floorings and three adhesives, exposed to three different aqueous solutions in the range of 11-13.1 pH. The conclusion drawn in this study is that the great majority of the secondary emission originates from the floor adhesive. The occurrence of adhesive and the amount of adhesive used have a significant influence on the emission rate. A critical pH value for degradation of the adhesive seems to lie somewhere between 11 and 13 pH.
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| 11. |
- Täubel, M., et al.
(författare)
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Co-occurrence of toxic bacterial and fungal secondary metabolites in moisture-damaged indoor environments
- 2011
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 21:5, s. 368-375
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Tidskriftsartikel (refereegranskat)abstract
- Toxic microbial secondary metabolites have been proposed to be related to adverse health effects observed in moisture-damaged buildings. Initial steps in assessing the actual risk include the characterization of the exposure. In our study, we applied a multi-analyte tandem mass spectrometry-based methodology on sample materials of severely moisture-damaged homes, aiming to qualitatively and quantitatively describe the variety of microbial metabolites occurring in building materials and different dust sample types. From 69 indoor samples, all were positive for at least one of the 186 analytes targeted and as many as 33 different microbial metabolites were found. For the first time, the presence of toxic bacterial metabolites and their co-occurrence with mycotoxins were shown for indoor samples. The bacterial compounds monactin, nonactin, staurosporin and valinomycin were exclusively detected in building materials from moist structures, while chloramphenicol was particularly prevalent in house dusts, including settled airborne dust. These bacterial metabolites are highly bioactive compounds produced by Streptomyces spp., a group of microbes that is considered a moisture damage indicator in indoor environments. We show that toxic bacterial metabolites need to be considered as being part of very complex and diverse microbial exposures in ’moldy’ buildings. Practical Implications: Bacterial toxins co-occur with mycotoxins in moisture-damaged indoor environments. These compounds are measurable also in settled airborne dust, indicating that inhalation exposure takes place. In attempts to characterize exposures to microbial metabolites not only mycotoxins but also bacterial metabolites have to be targeted by the analytical methods applied. We recommend including analysis of samples of outdoor air in the course of future indoor assessments, in an effort to better understand the outdoor contribution to the indoor presence of microbial toxins. There is a need for a sound risk assessment concerning the exposure to indoor microbial toxins at concentrations detectable in moisture-damaged indoor environments.
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| 12. |
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| 13. |
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| 14. |
- Pommer, Linda, et al.
(författare)
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Class separation of buildings with high and low prevalence of SBS by principal component analysis
- 2004
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Ingår i: Indoor Air. - : John Wiley & Sons. - 0905-6947 .- 1600-0668. ; 14:1, s. 16-23
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we were able to separate buildings with high and low prevalence of sick building syndrome (SBS) using principal component analysis. The prevalence of SBS was defined by the presence of at least one typical skin, mucosal and general (headache and fatigue) symptom. Data from the Swedish Office Illness Study describing the presence and level of chemical compounds in outdoor, supply, and room air, respectively, were evaluated together with information about the buildings in six models. When all data were included the most complex model was able to separate 71% of the high prevalence buildings from the low prevalence buildings. The most important variable that separates the high prevalence buildings from the low prevalence buildings was a more frequent occurrence or a higher concentration of compounds with shorter retention time in the high prevalence buildings. Elevated relative humidity in supply and room air and higher levels of total volatile organic compounds in outdoor and supply air were more common in high prevalence buildings. Ten building variables also contributed to the separation of the two classes of low and high prevalence buildings.
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| 15. |
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| 16. |
- Bakke, JV, et al.
(författare)
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Pet keeping and dampness in the dwelling : associations with airway infections, symptoms, and physiological signs from the ocular and nasal mucosa
- 2007
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 17:1, s. 60-69
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to utilize data from a study of occupational indoor environments to analyze symptoms and physiological signs in relation to the home environment. A medical investigation was performed at the workplace among university staff (n = 173) from four university buildings in Bergen, in March 2004. Tear film break up time (BUT) was measured by two methods. Nasal patency was measured by acoustic rhinometry. Nasal lavage fluid analysis (NAL) included eosinophilic cationic protein (ECP); myeloperoxidase (MPO), lysozyme and albumin. Atopy was assessed by total serum IgE and specific IgE (Phadiatop®). Totally 21%, 21%, 18%, 11%, and 27% had weekly ocular, nasal, facial dermal symptoms, headache and tiredness, respectively, 15% had a damp dwelling, and 20% had a cat or dog. Multiple linear or logistic regressions were applied, controlling for age gender, smoking, and environmental factors. Building dampness was associated with increased NAL-lysozyme (P = 0.02) and an increase of airway infections [odd ratio (OR) = 3.14, P = 0.04]. Pet keeping was associated with difficulties to concentrate (OR = 5.10, P = 0.001), heavy headedness (OR = 4.35, P = 0.004), four more days with tiredness per month (P = 0.04), and less airway infections (OR = 0.32; P = 0.02). In conclusion, pet keeping was associated with more central nervous system (CNS)-symptoms but less airway infections. Dampness in the dwelling may have inflammatory effects on the airway mucosa, possibly mediated via increased infection proneness.
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| 17. |
- Bakke, J V, et al.
(författare)
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Symptoms, complaints, ocular and nasal physiological signs in university staff in relation to indoor environment : temperature and gender interactions
- 2008
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 18:2, s. 131-143
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Tidskriftsartikel (refereegranskat)abstract
- Symptoms, signs, perceptions, and objective measures were studied in university buildings. Two problem buildings with a history of dampness and complaints were compared with two control buildings. Health investigations among university staff were performed at the workplace (n = 173) including tear film stability [non-invasive break-up time (NIBUT) and self-reported break-up time (SBUT)], nasal patency (acoustic rhinometry), nasal lavage fluid analysis [NAL: eosinophil cationic protein (ECP), myeloperoxidase (MPO), lysozyme and albumin] and atopy by total serum IgE and IgE antibodies (Phadiatop (R)). Exposure assessment included inspections, thermal and atmospheric climate at 56 points modelled for all work sites. Multiple regressions were applied, controlling for age and gender. Exposure differences between problem buildings and controls were small, and variations between rooms were greater. Workers in the problem buildings had more general and dermal symptoms, but not more objective signs than the others. Adjusted day NIBUT and SBUT increased at higher night air temperatures, with B (95% CI) 0.6 (0.04-1.2) and 1.3 (-0.02 to 2.5), respectively. Higher relative humidity at mean day air temperature < 22.1 degrees C was associated with adjusted NIBUT and SBUT, with B (95% CI) 0.16 (0.03-0.29) and 0.37 (-0.01 to 0.75), respectively. Air velocity below recommended winter values and reduced relative humidity in the range of 15-30% were associated with dry air and too low temperature.
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| 18. |
- Bergh, Caroline, et al.
(författare)
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Organophosphate and phthalate esters in air and settled dust – a multi-location indoor study
- 2011
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 21:1, s. 67-76
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports the abundance in indoor air and dust of eleven organophosphate esters and six phthalate esters. Both groups of these semi-volatile compounds are widely incorporated as additives into plastic materials used in the indoor environment, thus contributing to indoor exposure to industrial chemicals. Thirty sampling sites representing three different indoor environments (private homes, day care centers, and workplaces) in the Stockholm area, Sweden, were selected to obtain representative concentration profiles in both ambient air and settled dust. Eight of the target organophosphate esters and all six phthalate esters were found in both air and dust samples at all locations. The phthalate esters were more abundant than the organophosphate esters, typically ten times higher total concentrations. Especially interesting were the high levels of tributoxyethyl phosphate in the day care centers, the relatively high levels of chlorinated organophosphate esters in the air of workplaces and the overall high levels of diethylhexyl phthalate in dust. The air concentration profiles of the phosphate esters differed significantly between the three indoor environments, whereas the concentration profiles of the phthalate esters as well as their total concentrations were similar. The correlation between concentrations found in air and in dust was found to be weak.
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| 19. |
- Björklund, Justina A., et al.
(författare)
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Comparisons of polybrominated diphenyl ether and hexabromocyclododecane concentrations in dust collected with two sampling methods and matched breast milk samples
- 2012
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 22:4, s. 279-288
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Tidskriftsartikel (refereegranskat)abstract
- Household dust from 19 Swedish homes was collected using two different sampling methods: from the occupants own home vacuum cleaner after insertion of a new bag and using a researcher-collected method where settled house dust was collected from surfaces above floor level. The samples were analyzed for 16 polybrominated diphenyl ether (PBDE) congeners and total hexabromocyclododecane (HBCD). Significant correlations (r = 0.600.65, Spearman r = 0.470.54, P < 0.05) were found between matched dust samples collected with the two sampling methods for ?OctaBDE and ?DecaBDE but not for ?PentaBDE or HBCD. Statistically significantly higher concentrations of all PBDE congeners were found in the researcher-collected dust than in the home vacuum cleaner bag dust (VCBD). For HBCD, however, the concentrations were significantly higher in the home VCBD samples. Analysis of the bags themselves indicated no or very low levels of PBDEs and HBCD. This indicates that there may be specific HBCD sources to the floor and/or that it may be present in the vacuum cleaners themselves. The BDE-47 concentrations in matched pairs of VCBD and breast milk samples were significantly correlated (r = 0.514, P = 0.029), indicating that one possible exposure route for this congener may be via dust ingestion. Practical Implications The statistically significant correlations found for several individual polybrominated diphenyl ether (PBDE) congeners, ?OctaBDE and ?DecaBDE between the two dust sampling methods in this study indicate that the same indoor sources contaminate both types of dust or that common processes govern the distribution of these compounds in the indoor environment. Therefore, either method is adequate for screening ?OctaBDE and ?DecaBDE in dust. The high variability seen between dust samples confirms results seen in other studies. For hexabromocyclododecane (HBCD), divergent results in the two dust types indicate differences in contamination sources to the floor than to above-floor surfaces. Thus, it is still unclear which dust sampling method is most relevant for HBCD as well as for ?PentaBDE in dust and, further, which is most relevant for determining human exposure to PBDEs and HBCD.
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| 20. |
- Bodin, Lennart, et al.
(författare)
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Nasal hyperresponders and atopic subjects report different symptom intensity to air quality : a climate chamber study
- 2009
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 19:3, s. 218-225
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Tidskriftsartikel (refereegranskat)abstract
- Short-term exposure to dust and dust added with beta-(1,3)-d-glucan or aldehydes may cause sensory reactions. In random order, we exposed 36 volunteers in a climate chamber to clean air, office dust, dust with glucan, and dust with aldehydes. Three groups of subjects were exposed, eleven were non-atopic with nasal histamine hyperreactivity, 13 were non-atopic, and 12 were atopic. Subjective ratings of symptoms and general health were registered four times during four 6-h exposure sessions. Six symptom intensity indices were constructed. The nasal hyperreactive group had a high and time-dependent increase of mucous membrane irritations, whereas the atopic group had a low and stable rate of irritations with exposure time, close to the reference group (P = 0.02 for differences between the groups with respect to time under exposure for Weak Inflammatory Responses and P = 0.05 for Irritative Body Perception, significance mainly because of the nasal hyperreactive group). Exposure to dust, with or without glucan or aldehydes, showed increased discomfort measured by the index for Constant Indoor Climate, and dust with glucan had a similar effect for the index for Lower Respiratory Effects. For Psychological and Neurological Effects these were dependent on group affiliation, thus preventing a uniform statement of exposure effects for all three investigated groups.Opportunities for identifying persons with high or low sensitivity to low-level exposures are important in preventive medicine and will reduce intra-group variability and thus increase the power of experimental and epidemiological studies searching for correlations between exposures and health effects. The contrast between nasal hyperreactive on one side and atopic and reference subjects on the other side is particularly important. The atopic group indicated a non-homogenous reaction depending on their hyperreactive status, a finding that could be important but needs further confirmation.
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| 21. |
- Bornehag, C G, et al.
(författare)
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'Dampness' at home and its association with airway, nose, and skin symptoms among 10,851 preschool children in Sweden: a cross-sectional study.
- 2005
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Ingår i: Indoor air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 15 Suppl 10, s. 48-55
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Tidskriftsartikel (refereegranskat)abstract
- There is convincing epidemiological evidence that 'dampness' in buildings is associated with respiratory effects. In order to identify health-relevant exposures in buildings with 'dampness', the study 'Dampness in Buildings and Health' (DBH) was initiated. In the first step of the study, cross-sectional data on home characteristics including 'dampness' problems, and symptoms in airway, nose, and skin among 10,851 children (1-6 years), were collected by means of a questionnaire to the parents. The prevalence of wheezing during the last 12 months was 18.9% and doctor-diagnosed asthma 5.4%. Rhinitis during the last 12 months was reported for 11.1% of the children and eczema during the last 12 months 18.7%. Gender, allergic symptoms among parents, and age of the child were associated with symptoms. Water leakage was reported in 17.8% of the buildings, condensation on windows in 14.3%, and detached flooring materials in 8.3%. Visible mould or damp spots were reported in only 1.5% of the buildings. The four 'dampness' indices were associated to higher prevalence of symptoms in both crude and adjusted analysis. Furthermore, it was found that the combination of water leakage in the home and PVC as flooring material in the child's or parent's bedroom was associated to higher prevalence of symptoms among children. However, the interpretation of this finding is unclear. The combination of water leakage and PVC may be a proxy, for example, reconstruction because of water damages. PRACTICAL IMPLICATIONS: The study have showed that moisture-related problems in buildings are a risk factor for asthma and allergic symptoms among preschool children. The recommendation to the general public is to remediate damp buildings.
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| 22. |
- Bröms, Kristina, et al.
(författare)
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A nationwide study of indoor and outdoor environments in allergen avoidance and conventional daycare centers in Sweden
- 2006
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 16:3, s. 227-35
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Tidskriftsartikel (refereegranskat)abstract
- Sweden has had specialized 'allergen avoidance daycare centers' (AADC) since 1979. The aim was to compare AADC with ordinary daycare centers (ODC). Through contacts with municipalities and hospitals, 72 AADC were identified. For each AADC, the two nearest ODCs served as controls. A questionnaire was sent to the local directors of the 216 daycare centers (531 sections), 83% responded. A total of 39% of the ODCs had ever had dampness/molds, 12% were near (<500 m) stables/farms, 23% were closer than 50 m to a heavy trafficked road, and 13% were exposed to wood smoke in winter. Only 11% of the AADCs had any child with furred pets at home, while 97% of the ODCs had children with furred pets. Bans on smoking at home and on perfumes were more common at the AADCs (P = 0.001). Fewer AADCs had PVC floors (OR = 0.53; P = 0.01), dampness/molds (OR = 0.55; P = 0.04), shelves (OR 3.03; P = 0.001), curtains (OR = 1.67; P = 0.047), and flowers (OR = 0.03; P < 0.001), while more had daily floor cleaning (OR = 19.9; P = 0.004), weekly wiping of furniture (OR = 11.0; P = 0.001), and washing of pillows/mattresses (OR = 2.74; P = 0.005) and curtains (OR = 9.07; P = 0.001). In conclusion, allergy avoidance daycare centers differ from other daycare centers, and may have better indoor environments. PRACTICAL IMPLICATIONS: There is a need to improve the indoor environments of daycare centers, including reduction of building dampness and molds. Allergen avoidance daycare centers (AADC) in Sweden differ from ordinary daycare centers in many respects, with fewer indoor and building factors related to dust, allergens and irritants. This shows that the indoor environments of daycare centers can be improved. Data suggest that AADC may have lower levels of pet allergens, and this is beneficial for children with pet allergy. The effects of these improvements on indoor exposures and health of the children need to be further evaluated.
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| 23. |
- Cai, G-H, et al.
(författare)
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Quantitative PCR analysis of fungal DNA in Swedish day care centers and comparison with building characteristics and allergen levels
- 2009
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 19:5, s. 392-400
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Tidskriftsartikel (refereegranskat)abstract
- Sweden has had allergen-avoidance day care centers (AADCs) since 1979. The aim of this study was to measure fungal DNA by quantitative polymerase chain reaction (qPCR), a new method, in AADCs and ordinary day care centers (ODCs) and examine associations between allergen levels and building characteristics. Dust samples were collected by swabbing doorframes, vacuum-cleaning, and using Petri dishes. In total, 11 AADCs and 11 ODCs were studied (70 rooms). Total fungal DNA, measured by qPCR in the swab dust, was detected in 89%, Aspergillus or Penicillium (Asp/Pen) DNA in 34%, and Stachybotrys chartarum DNA in 6% of the rooms. Total fungal DNA was significantly higher in rooms with linoleum floor (P = 0.02), textile carpets (P = 0.03), reported dampness/molds (P = 0.02) and reported odor (P < 0.001) in the buildings, and significantly lower in wooden facade buildings (P = 0.003). Reported odor was related to the amount of sieved fine dust, reported dampness/molds and type of building construction. Total fungal DNA was related to cat, dog, horse and total allergen levels (P = 0.003) in the day care centers. In conclusion, total fungal DNA is related to reported dampness/molds, reported odor, and type of wall construction. The association between fungal and allergen contamination indicated a general 'hygiene factor' related to biological contaminants. Practical Implications The associations between fungal DNA, reported dampness/molds, and odor support the view that buildings with odor problems should be investigated for possible hidden fungal growth. There is a need to measure fungal biomass in different types of building constructions by monitoring fungal DNA. Analysis of fungal DNA with quantitative PCR can be a fast and practical way to study indoor fungal contamination. Swabbing dust from the doorframe of the main entrance to the room can be a convenient method of sampling dust for fungal DNA analysis. The high prevalence of reported dampness/molds and the common occurrence of fungal DNA indicate the need to improve the indoor environment of Swedish day care centers.
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| 24. |
- Chen, C-M, et al.
(författare)
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Geographical variation and the determinants of domestic endotoxin levels in mattress dust in Europe
- 2012
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 22:1, s. 24-32
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Tidskriftsartikel (refereegranskat)abstract
- Endotoxin exposures have manifold effects on human health. The geographical variation and determinants of domestic endotoxin levels in Europe have not yet been extensively described. To investigate the geographical variation and determinants of domestic endotoxin concentrations in mattress dust in Europe using data collected in the European Community Respiratory Health Survey follow-up (ECRHS II). Endotoxin levels were measured in mattress dust from 974 ECRHS II participants from 22 study centers using an immunoassay. Information on demographic, lifestyle, and housing characteristics of the participants was obtained in face-to-face interviews. The median endotoxin concentration in mattress dust ranged from 772 endotoxin units per gram (EU/g) dust in Reykjavik, Iceland, to 4806 EU/g in Turin, Italy. High average outdoor summer temperature of study center, cat or dog keeping, a high household crowding index, and visible damp patches in the bedroom were significantly associated with a higher endotoxin concentrations in mattress dust. There is a large variability in domestic endotoxin levels across Europe. Average outdoor summer temperature of study center, which explains only 10% of the variation in domestic endotoxin level by center, is the strongest meteorological determinant. The observed variation needs to be taken into account when evaluating the health effects of endotoxin exposures in international contexts. PRACTICAL IMPLICATIONS: The incoherent observations of the health effects of endotoxin may be partly owing to the geographical heterogeneity of endotoxin exposure. Therefore, the observed variation should be considered in further studies. Measurements of indoor endotoxin are recommended as an indicator for the level of exposures of individual domestic environments.
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| 25. |
- 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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| 26. |
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| 27. |
- Clausen, Geo, et al.
(författare)
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Children's health and its association with indoor environments in Danish homes and daycare centres - methods
- 2012
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 22:6, s. 467-475
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Tidskriftsartikel (refereegranskat)abstract
- The principle objective of the Danish research program 'Indoor Environment and Children's Health' (IECH) was to explore associations between various exposures that children experience in their indoor environments (specifically their homes and daycare centers) and their well-being and health. The targeted health endpoints were allergy, asthma, and certain respiratory symptoms. The study was designed with two stages. In the first stage, a questionnaire survey was distributed to more than 17000 families with children between the ages of 1 and 5. The questionnaire focused on the children's health and the environments within the homes they inhabited and daycare facilities they attended. More than 11000 questionnaires were returned. In the second stage, a subsample of 500 children was selected for more detailed studies, including an extensive set of measurements in their homes and daycare centers and a clinical examination; all clinical examinations were carried out by the same physician. In this study, the methods used for data collection within the IECH research program are presented and discussed. Furthermore, initial findings are presented regarding descriptors of the study population and selected characteristics of the children's dwellings and daycare centers. Practical Implications: This study outlines methods that might be followed by future investigators conducting large-scale field studies of potential connections between various indoor environmental factors and selected health endpoints. Of particular note are (i) the two-stage design - a broad questionnaire-based survey followed by a more intensive set of measurements among a subset of participants who have been selected based on their responses to the questionnaire; (ii) the case-base approach utilized in the stage 2 in contrast to the more commonly used case-control approach; (iii) the inclusion of the children's daycare environment when conducting intensive sampling to more fully capture the children's total indoor exposure; and (iv) all clinical examinations conducted by the same physician. We recognize that future investigators are unlikely to fully duplicate the methods outlined in this study, but we hope that it provides a useful starting point in terms of factors that might be considered when designing such a study.
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| 28. |
- Engvall, Karin, et al.
(författare)
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Ocular, nasal, dermal and respiratory symptoms in relation to heating, ventilation, energy conservation and reconstruction of older multi-family houses
- 2003
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 13:3, s. 206-211
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to study relationships between symptoms compatible with the sick building syndrome, type of heating and ventilation system, energy saving, and reconstruction in older dwellings. In Stockholm, 4815 inhabitants in 231 multi-family buildings built before 1961 were randomly selected, of whom 3241 participated (77%). Symptoms and personal factors were assessed by a postal questionnaire. Independent information on building characteristics, and energy saving measures was gathered from the building owners. Multiple logistic regression analysis was applied to calculate odds ratios (OR) adjusting for age, gender, hay fever, current smoking, population density, type of ventilation, type of heating system, and ownership of the building. Subjects in buildings with a mechanical ventilation system had less ocular and nasal symptoms (OR = 0.29-0.85). Heating by electric radiators, and wood heating was associated with an increase of most symptoms (OR = 1.18-1.74). In total, 48% lived in buildings that had gone through at least one type of reconstruction or energy saving remedies during the latest 10 years, including exchange of heating or ventilation system, and sealing measures (exchange of windows, sealing of window frames, roof/attic insulation, and phasade insulation). Energy saving was associated with both a decrease and increase of different symptoms. Major reconstruction of the interior of the building was associated with an increase of most symptoms (OR = 1.09-1.90), and buildings with more than one sealing measure had an increase of ocular, nasal symptoms, headache and tiredness (OR = 1.22-2.49). In conclusion, major reconstruction of the interior, direct heated electric radiators, wood heating, and multiple sealing of buildings were associated with an increase of some symptoms. The study supports the view that mechanical ventilation in dwellings is beneficial from a health point of view.
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| 29. |
- Engvall, Karin, et al.
(författare)
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The Stockholm Indoor Environment Questionnaire (SIEQ) : A sociological based tool for assessment of indoor environment and health in dwellings
- 2004
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 14:1, s. 24-33
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to develop and validate a standardized questionnaire - the Stockholm Indoor Environment Questionnaire (SIEQ). The validation procedure was based on sociological principles and test procedures for validation. The indicators of indoor environment are air quality, thermal climate, noise, and illumination. The indicators of health are symptoms comprised in the sick building syndrome (SBS). The questionnaire also contains questions about the apartment, individual behavior, and personal factors. The everyday language describing the building and its function was first obtained by qualitative personal interviews, then by standardized questions. The interview questionnaire was transformed into a postal self-administered questionnaire. The reduction of the questionnaire was based on correlation analysis. It was found that to obtain a good validity, general questions are not sufficient, but specific question on perceptions and observations are needed. Good test-retest agreement was found both on an area level, building level, and individually. For each indicator, a set of questions are constructed and validated. SIEQ has been used in several studies, and the results are presented in graphic problem profiles. Reference data has been calculated for the Stockholm area.
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| 30. |
- Ernstgård, Lena, et al.
(författare)
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Acute effects of exposure to 1 mg/m(3) of vaporized 2-ethyl-1-hexanol in humans
- 2010
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 20:2, s. 168-175
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Tidskriftsartikel (refereegranskat)abstract
- The objective was to assess acute effects from controlled exposure of volunteers to 2-ethyl-1-hexanol, a volatile organic compound that is often found in indoor air. Sixteen males and fourteen females were in random order exposed to 1 mg/m3 of vapors of 2-ethyl-1-hexanol or to clean air (control exposure) in an exposure chamber during 2 h at rest. The subjects performed symptom ratings on Visual Analog Scales. During exposure to 2-ethyl-1-hexanol subjective ratings of smell and eye discomfort were minimally but significantly increased. Ratings of nasal irritation, throat irritation, headache, dyspnoea, fatigue, dizziness, nausea, and intoxication were not significantly affected. No exposure-related effects on measurement of blinking frequency by electromyography, measurement of the eye break-up time, vital staining of the eye, nasal lavage biomarkers, transfer tests, spirometric and rhinometric measures were seen. No differences in response were seen between sexes or between atopics and non-atopics
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| 31. |
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| 32. |
- Holmberg, Sture, et al.
(författare)
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Airflow and particle control with different ventilation systems in a classroom
- 2003
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 13:2, s. 200-204
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Tidskriftsartikel (refereegranskat)abstract
- Most ventilation and air conditioning systems are designed without much concern about how settling particles behave in ventilation air flows. For displacement ventilation systems, designers normally assume that all pollutants follow the buoyant air flow into an upper zone, where they are evacuated. This is, however, not always true. Previous studies show that high concentrations of settling respirable particles can be found in the breathing zone, and that the exposure rates can be a health hazard to occupants. The emphasis here is on how ventilation systems should be designed to minimize respirable airborne particles in the breathing zone. The supply and exhaust conditions of the ventilation air flow are shown to play an important role in the control of air quality. Computer simulation programs of computational fluid dynamics (CFD) type are used. Particle concentrations, thermal conditions and modified ventilation system solutions are reported.
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| 33. |
- Hsu, N. -Y, et al.
(författare)
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Predicted risk of childhood allergy, asthma, and reported symptoms using measured phthalate exposure in dust and urine
- 2012
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 22:3, s. 186-199
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Tidskriftsartikel (refereegranskat)abstract
- The associated risk of phthalate exposure, both parent compounds in the home and their metabolites in urine, to childhood allergic and respiratory morbidity, after adjusting for exposures of indoor pollutants, especially bioaerosols, was comprehensively assessed. Levels of five phthalates in settled dust from the homes of 101 children (39 years old) were measured, along with their corresponding urinary metabolites. Other environmental risk factors, including indoor CO2, PM2.5, formaldehyde, 1,3-beta-d-glucan, endotoxin, allergen and fungal levels, were concomitantly examined. Subjects health status was verified by pediatricians, and parents recorded observed daily symptoms of their children for the week that the home investigation visit took place. Significantly increased level of benzylbutyl phthalate, in settled dust, was associated with test case subjects (allergic or asthmatic children). Higher levels of dibutyl phthalate and its metabolites, mono-n-butyl phthalate, and mono-2-ethylhexyl phthalate were found to be the potential risk factors for the health outcomes of interest. Similarly, indoor fungal exposure remained a significant risk factor, especially for reported respiratory symptoms. The relative contribution from exposure to phthalates and indoor biocontaminants in childhood allergic and respiratory morbidity is, for the first time, quantitatively assessed and characterized. Practical Implications For asthmatic and allergic children living in subtropical and highly developed environments like homes in Taiwan, controlling environmental exposure of phthalates may be viewed as equally important as avoiding indoor microbial burdens, for the management of allergy-related diseases. It is also recognized that multidisciplinary efforts will be critical in realizing the true underlying mechanisms associated with these observations.
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| 34. |
- Hägerhed-Engman, L, et al.
(författare)
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Low home ventilation rate in combination with mouldy odor from the building structure increase the risk for allergic symptoms in children
- 2009
-
Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 19:3, s. 184-192
-
Tidskriftsartikel (refereegranskat)abstract
- There are consistent findings on associations between asthma and allergy symptoms and residential mold and moisture. However, definitions of ‘dampness’ in studies are diverse because of differences in climate and building construction. Few studies have estimated mold problems inside the building structure by odor assessments. In a nested case-control study of 400 Swedish children, observations and measurements were performed in their homes by inspectors, and the children were examined by physicians for diagnoses of asthma, eczema, and rhinitis. In conclusion, we found an association between moldy odor along the skirting board and allergic symptoms among children, mainly rhinitis. No associations with any of the allergic symptoms were found for discoloured stains, ‘floor dampness’ or a general mold odor in the room. A moldy odor along the skirting board can be a proxy for hidden moisture problem inside the outer wall construction or in the foundation construction. There are indications that such dampness problems increase the risk for sensitization but the interpretation of data in respect of sensitization is difficult as about 80% of the children with rhinitis were sensitized. Furthermore, low ventilation rate in combination with moldy odor along the skirting board further increased the risk for three out of four studied outcomes, indicating that the ventilation rate is an effect modifier for indoor pollutants.
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| 35. |
- Kim, Jeong-Lim, et al.
(författare)
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Indoor molds, bacteria, microbial volatile organic compounds and plasticizers in schools : associations with asthma and respiratory symptoms in pupils
- 2007
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 17:2, s. 153-163
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Tidskriftsartikel (refereegranskat)abstract
- We investigated asthma and atopy in relation to microbial and plasticizer exposure. Pupils in eight primary schools in Uppsala (Sweden) answered a questionnaire, 1014 (68%) participated. Totally, 7.7% reported doctor-diagnosed asthma, 5.9% current asthma, and 12.2% allergy to pollen/pets. Wheeze was reported by 7.8%, 4.5% reported daytime breathlessness, and 2.0% nocturnal breathlessness. Measurements were performed in 23 classrooms (May–June), 74% had <1000 ppm CO2 indoors. None had visible mold growth or dampness. Mean total microbial volatile organic compound (MVOC) concentration was 423 ng/m3 indoors and 123 ng/m3 outdoors. Indoor concentration of TMPD-MIB (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, Texanol) and TMPD-DIB (2,2,4-trimethyl-1,3-pentanediol diisobutyrate, TXIB), two common plasticizers, were 0.89 and 1.64 μg/m3, respectively. MVOC and plasticizer concentration were correlated (r = 0.5; P < 0.01). Mold concentration was 360 cfu/m3 indoors and 980 cfu/m3 outdoors. At higher indoor concentrations of total MVOC, nocturnal breathlessness (P < 0.01) and doctor-diagnosed asthma (P < 0.05) were more common. Moreover, there were positive associations between nocturnal breathlessness and 3-methylfuran (P < 0.01), 3-methyl-1-butanol (P < 0.05), dimethyldisulfide (P < 0.01), 2-heptanone (P < 0.01), 1-octen-3-ol (P < 0.05), 3-octanone (P < 0.05), TMPD-MIB (P < 0.05), and TMPD-DIB (P < 0.01). TMPD-DIB was positively associated with wheeze (P < 0.05), daytime breathlessness (P < 0.05), doctor-diagnosed asthma (P < 0.05), and current asthma (P < 0.05). In conclusion, exposure to MVOC and plasticizers at school may be a risk factor for asthmatic symptoms in children.
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| 36. |
- Kim, Jeong-Lim, et al.
(författare)
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Respiratory symptoms, asthma and allergen levels in schools : comparison between Korea and Sweden
- 2007
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 17:2, s. 122-129
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Tidskriftsartikel (refereegranskat)abstract
- We studied reports on respiratory symptoms, asthma and atopic sensitisation in relation to allergen contamination in Korean schools and compared with data from a previous Swedish study performed in eight primary schools. Korean pupils (n = 2365) in 12 primary schools first completed a questionnaire. Then airborne and settled dust were collected from 34 classrooms and analyzed for allergens by ELISA. In both countries, boys reported more symptoms. The prevalence of wheeze was similar, while daytime [odds ratio (OR) = 14.0, 95% confidence interval (CI) = 9.0–21.9] and nocturnal breathlessness (OR = 3.1, 95% CI = 1.5–6.4) were much higher among Korean students. In Korean schools, dog allergen (Can f 1) was the most common followed by mite allergen (Der f 1), while cat (Fel d 1), dog, and horse allergen (Equ cx) were abundant in Sweden. Moreover, CO2 levels were high in most Korean schools (range 907–4113 ppm). There was an association between allergen levels in dust and air samples, and number of pet-keepers in the classrooms. In conclusion, allergen contamination in Korean schools may be an important public issue.
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| 37. |
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| 38. |
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| 39. |
- Lindgren, Torsten, et al.
(författare)
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Perception of cabin air quality in airline crew related to air humidification, on intercontinental flights
- 2007
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 17:3, s. 204-210
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Tidskriftsartikel (refereegranskat)abstract
- The influence of air humidification in aircraft, on perception of cabin air quality among airline crew (N = 71) was investigated. In-flight investigations were performed in the forward part and in the aft part on eight intercontinental flights with one Boeing 767 individually, equipped with an evaporation humidifier combined with a dehumidifying unit, to reduce accumulation of condensed water in the wall construction. Four flights had the air humidification active when going out, and turned off on the return flight. The four others had the inverse humidification sequence. The sequences were randomized, and double blind. Air humidification increased relative air humidity (RH) by 10% in forward part, and by 3% in aft part of the cabin and in the cockpit. When the humidification device was active, the cabin air was perceived as being less dry (P = 0.008), and fresher (P = 0.002). The mean concentration of viable bacteria (77–108 cfu/m3), viable molds (74–84 cfu/m3), and respirable particles (1–8 μg/m3) was low, both during humidified and non-humidified flights. On flights with air humidification, there were less particles in the forward part of the aircraft (P = 0.01). In conclusion, RH can be slightly increased by using ceramic evaporation humidifier, without any measurable increase of microorganisms in cabin air. The cabin air quality was perceived as being better with air humidification.
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| 40. |
- Mi, Y-H, et al.
(författare)
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Current asthma and respiratory symptoms among pupils in Shanghai, China : influence of building ventilation, nitrogen dioxide, ozone, and formaldehyde in classrooms
- 2006
-
Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 16:6, s. 454-464
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Tidskriftsartikel (refereegranskat)abstract
- We investigated 10 naturally ventilated schools in Shanghai, in winter. Pupils (13-14 years) in 30 classes received a questionnaire, 1414 participated (99%). Classroom temperatures were 13-21 degrees C (mean 17 degrees C), relative air humidity was 36-82% (mean 56%). The air exchange rate was 2.9-29.4 ac/h (mean 9.1), because of window opening. Mean CO2 exceeded 1000 ppm in 45% of the classrooms. NO2 levels were 33-85 mu g/m(3) indoors, and 45-80 mu g/m(3) outdoors. Ozone were 1-9 mu g/m(3) indoors and 17-28 mu g/m(3) outdoors. In total, 8.9% had doctors' diagnosed asthma, 3.1% wheeze, 23.0% daytime breathlessness, 2.4% current asthma, and 2.3% asthma medication. Multiple logistic regression was applied. Observed indoor molds was associated with asthma attacks [odds ratio (OR) = 2.40: P < 0.05]. Indoor temperature was associated with daytime breathlessness (OR = 1.26 for 1 C; P < 0.001), and indoor CO2 with current asthma (OR = 1.18 for 100 ppm; P < 0.01) and asthma medication (OR = 1.15 for 100 ppm; P < 0.05). Indoor NO2 was associated with current asthma (OR = 1.51 for 10 mu g/m(3); P < 0.01) and asthma medication (OR = 1.45 for 10 mu g/m(3); P < 0.01). Outdoor NO2 was associated with current asthma (OR = 1.44 for 10 mu g/m(3); P < 0.05). Indoor and outdoor ozone was negatively associated with daytime breathlessness. In conclusion, asthma symptoms among pupils in Shanghai can be influenced by lack of ventilation and outdoor air pollution from traffic.
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| 41. |
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| 42. |
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| 43. |
- Munir, Abdul Kashem Mohamma, 1958-, et al.
(författare)
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Variability of airborne cat allergen, Fel d1, in a public place
- 2003
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 13:4, s. 353-358
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Tidskriftsartikel (refereegranskat)abstract
- Allergen exposure is a risk to develop an IgE-mediated sensitization. The amount of allergen inhaled per unit time should be related to the amount present in the air, i.e. airborne allergen. Thus, measuring allergen levels in the air would be more relevant than measuring allergen levels in dust. Allergens are present in the air in very minute quantities and usually become airborne after disturbance. Large variation of allergen levels have been found in dust. In this study, we measured variability of airborne cat allergen, Fel d1, in a public place using a high-volume air-sampler. We also studied the distribution and relationship between dust and airborne cat allergens in homes and schools. Air samples were collected at three different airflow rates, i.e. 55, 40, and 30 m3 of air per hour. The concentration of airborne Fel d1 in the community gymnastic hall varied from 1 to 10 pg/m3 within a period of 3 weeks, at airflow rates 55-30 m3/h. The coefficient of variation for repeated samplings was 14-43% (day-to-day variation) and 27-38% (within-day variation). As expected, higher levels of airborne cat allergens were found in homes with cats than in cat-free environments. There was a significant relationship between cat allergen levels in dust and air (r = 0.7, P < 0.01). Our study demonstrates that when measuring airborne cat allergen a large variation is observed within a day and between days. The large variability of measurement may be explained by the disturbance in the environments. We suggest, that when exposure assessment is made the environment in question should be analyzed, if possible in several occasions.
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| 44. |
- Norbäck, D, et al.
(författare)
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An experimental study on effects of increased ventilation flow on students' perception of indoor environment in computer classrooms.
- 2008
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 18:4, s. 293-300
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Tidskriftsartikel (refereegranskat)abstract
- The effects of ventilation in computer classrooms were studied with university students (n = 355) in a blinded study, 31% were women and 3.8% had asthma. Two classrooms had a higher air exchange (4.1-5.2 ac/h), two others had a lower air exchange (2.3-2.6 ac/h). After 1 week, ventilation conditions were shifted. The students reported environmental perceptions during the last hour. Room temperature, RH, CO2, PM10 and ultra-fine particles were measured simultaneously. Mean CO2 was 1185 ppm at lower and 922 ppm at higher air exchange. Mean temperature was 23.2 degrees C at lower and 22.1 degrees C at higher air exchange. After mutual adjustment (temperature, RH, CO2, air exchange), measured temperature was associated with a perception of higher temperature (P < , 0.001), lower air movement (P < , 0.001), and poorer air quality (P < , 0.001). Higher air exchange was associated with a perception of lower temperature (P < , 0.001), higher air movement (P = 0.001), and better air quality (P < , 0.001). In the longitudinal analysis (n = 83), increased air exchange caused a perception of lower temperature (P = 0.002), higher air movement (P < , 0.001), better air quality (P = 0.001), and less odor (P = 0.02). In conclusion, computer classrooms have CO2 levels above 1000 ppm and temperatures above 22 degrees C. Increased ventilation from 7 l/s per person to 10-13 l/s per person can improve thermal comfort and air quality.
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| 45. |
- Norbäck, Dan, et al.
(författare)
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Respiratory symptoms, perceived air quality and physiological signs in elementary school pupils in relation to displacement and mixing ventilation system : an intervention study
- 2011
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 21:5, s. 427-437
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Tidskriftsartikel (refereegranskat)abstract
- Schools may be poorly ventilated and may contain furry pet allergens, particles and microorganisms. We studied health effects when changing from mixing ceiling ventilation to two types of displacement ventilation, front ventilation system (FVS) and floor master system (FMS). The study included pupils in three elementary school classes (N = 61), all with floor heating. One class received blinded interventions; the two others were unchanged (controls). Ventilation flow and supply air temperature was kept constant. The medical investigation included tear film stability (BUT), nasal patency and a questionnaire containing rating scales. When changing from mixing ventilation to FVS, the pupils (N = 26) perceived better air quality (P = 0.006) and less dyspnoea (P = 0.007) as compared to controls (N = 35), and BUT was improved (P = 0.03). At desk level, mean CO(2) was reduced from 867 to 655 ppm. Formaldehyde and viable bacteria were numerically lower, while total bacteria and molds were higher with displacement ventilation. There was no difference in symptoms or signs when changing from FVS to FMS. Cat (Der p1), dog (Can f1) and horse allergen (Equ cx) were common in air at all conditions. In conclusion, displacement ventilation may have certain positive health effects among pupils, as compared to conventional mixing ceiling systems.
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| 46. |
- Pommer, Linda, et al.
(författare)
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An experimental comparison of a kinetic model for the reaction of α-pinene and Δ3-carene with ozone and nitrogen oxides
- 2004
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Ingår i: Indoor Air. - Köpenhamn : Blackwell Munksgaard. - 0905-6947 .- 1600-0668. ; 14:S8, s. 75-83
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Tidskriftsartikel (refereegranskat)abstract
- A kinetic model was compiled to simulate reactions of the monoterpenes, α-pinene and Δ3-carene, with O3, NO2 and NO. The influence of different initial settings of O3, NO2 and NO on the monoterpene reaction was evaluated. At initial levels of 75 p.p.b. of O3, NO2 and NO each, 1.5% of α-pinene and 1.1% of Δ3-carene were calculated to react after 215 s. The corresponding experimental results showed that 9.3–12.2% of α-pinene and 9.9–11.7% of Δ3-carene reacted. The calculated levels of O3, NO2 and NO were compared to experimental measurements and were shown to correspond well. However, comparison of the amount of monoterpene reacted between calculated and experimental results, demonstrated that the calculations underestimated the amount of monoterpene reacted in the experimental chamber. The difference between experimental and calculated results could, e.g., be the effect of surfaces and the presence of water, which are parameters not included in the kinetic model known to have influence on these reactions.
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| 47. |
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| 48. |
- Runeson, Roma, et al.
(författare)
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Personal and psychosocial factors and symptoms compatible with sick building syndrome in the Swedish workforce
- 2006
-
Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; 16:6, s. 445-453
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Tidskriftsartikel (refereegranskat)abstract
- A random sample of 1000 subjects (20-65 years of age) received a postal questionnaire regarding sick building syndrome (SBS), including the three-dimensional model of demand-control-support (DCS). The response rate was 70% (n = 695), and 532 were occupationally active. Female gender and atopy were the main predictors of symptoms. Eye symptoms were more common at low social support combined with strained work situation [odds ratio (OR) 2.37], and at high social support combined with active work situation (OR 3.00). Throat symptoms were more common at low social support combined with either passive (OR 1.86) or strained situation (OR 2.42). Tiredness was more common at low social support combined with either passive (OR 2.41), strained (OR 2.25), or active situation (OR 1.87), and at high social support combined with active work situation (OR 1.83). Low social support combined with either passive (P = 0.01) or strained job situation (P = 0.01) was associated with a higher symptom score (SC). The lowest SC was found at a relaxed work situation, irrespective of social support. In conclusion, female gender, low age, asthma, atopy and psychosocial work environment are associated with symptoms. The three-dimensional model can predict symptoms compatible with SBS, but in a more complex way than earlier research indicated.
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| 49. |
- Runeson, Roma, et al.
(författare)
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The infuence of personality, measured by the Karolinska Scales of Personality (KSP), on symptoms among subjects in suspected sick buildings
- 2004
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Ingår i: Indoor Air. - : Hindawi Limited. - 0905-6947 .- 1600-0668. ; :14, s. 394-404
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to study possible relationships between personality traitsas measured by the Karolinska Scales of Personality (KSP), a self-report personalityinventory based on psychobiological theory, and medical symptoms, insubjects with previous work history in suspected sick buildings. The studycomprised 195 participants from 19 consecutive cases of suspected sick buildings,initially collected in 1988–92. In 1998–89, the KSP inventory and a symptomsquestionnaire were administered in a postal follow-up study. There were 16questions on symptoms, including symptoms from the eyes, nose, throat, skin,and headache, tiredness, and a symptom score (SC), ranging from 0 to 16, wascalculated. The questionnaire also requested information on personal factors,including age, gender, smoking habits, allergy and diagnosed asthma. The KSPratings in the study group did not differ from the mean personality scale normscores, calculated from an external reference group. Females had higher scoresfor somatic anxiety (P < 0.01), muscular tension (P < 0.001), psychic anxiety(P < 0.01), psychasthenia (P < 0.05), indirect aggression (P < 0.05), and guilt(P < 0.05), while males scored higher on detachment (P < 0.001). Subjects withhigher SC were found to display higher degree of somatic anxiety (P < 0.001),muscular tension (P < 0.001), psychic anxiety (P < 0.001), psychasthenia(P < 0.001), inhibition of aggression (P < 0.05), detachment (P < 0.05), suspicion(P < 0.01), indirect aggression (P < 0.01), and verbal aggression(P < 0.05). In addition, ocular, respiratory, dermal, and systemic symptoms(headache and tiredness) were significantly related to anxiety- and aggressivityrelatedscales. There were associations between personality scales and change ofsymptom score (SC) during the 9-year period. The associations between KSPpersonality traits and symptoms were more pronounced in females. In conclusion,there are gender differences in personality and SBS symptoms. Personalitymay play a role in the occurrence of symptoms studied in indoor environmentalepidemiology. Our results support a view that measurement of personality couldbe of value in future studies and vulnerability to environmental stress.
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| 50. |
- Sahlberg, Bo, 1963-, et al.
(författare)
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Onset of mucosal, dermal, and general symptoms in relation to biomarkers and exposures in the dwelling : a cohort study from 1992 to 2002
- 2012
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Ingår i: Indoor Air. - : John Wiley & Sons. - 0905-6947 .- 1600-0668. ; 22:4, s. 331-338
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Tidskriftsartikel (refereegranskat)abstract
- We examined the associations between biomarkers of allergy and inflammation, indoor environment in dwellings, and incidence and remission of symptoms included in the sick building syndrome (SBS) and changes in the home environment of 452 adults who were followed from 1992 to 2002 within the Uppsala part of the European Community Respiratory Health Survey (ECRHS). The 10-year incidence (onset) of general, mucosal, and dermal symptoms was 8.5%, 12.7%, and 6.8%, respectively. Dampness or indoor molds at baseline was a predictor of incidence of general (relative risk [RR] = 1.98), mucosal (RR = 2.28), and dermal symptoms (RR = 1.91). Women had higher incidence of general (RR = 1.74) and mucosal symptoms (RR = 1.71). Indoor painting increased the incidence of general symptoms (RR = 1.62). Bronchial responsiveness (BR), eosinophil counts in blood, total IgE and eosinophilic cationic protein (ECP) in serum at baseline were predictors of incidence of SBS. At follow-up, BR, total IgE, and C-reactive protein (CRP ) were associated with increased incidence of SBS. Moreover, subjects with doctor-diagnosed asthma at baseline had a higher incidence of general (RR = 1.65) and mucosal symptoms (RR = 1.97). In conclusion, female gender, dampness or indoor molds, indoor painting, and biomarkers of allergy and inflammation were associated with a higher incidence of SBS symptoms, in particular mucosal symptoms.
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