Browsing by Subject "DAMPNESS"

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  • Savelieva, Kateryna; Marttila, Tero; Lampi, Jussi; Ung-Lanki, Sari; Elovainio, Marko; Pekkanen, Juha (2019)
  • Korpelainen, Helena; Pietiläinen, Maria (2017)
    In the present study, we conducted DNA metabarcoding (the nuclear ITS2 region) for indoor fungal samples originating from two nursery schools with a suspected mould problem (sampling before and after renovation), from two university buildings, and from an old farmhouse. Good-quality sequences were obtained, and the results showed that DNA metabarcoding provides high resolution in fungal identification. The pooled proportions of sequences representing filamentous ascomycetes, filamentous basidiomycetes, yeasts, and other fungi equalled 62.3%, 8.0%, 28.3%, and 1.4%, respectively, and the total number of fungal genera found during the study was 585. When comparing fungal diversities and taxonomic composition between different types of buildings, no obvious pattern was detected. The average pairwise values of Sorensen(Chao) indices that were used to compare similarities for taxon composition between samples among the samples from the two university buildings, two nurseries, and farmhouse equaled 0.693, 0.736, 0.852, 0.928, and 0.981, respectively, while the mean similarity index for all samples was 0.864. We discovered that making explicit conclusions on the relationship between the indoor air quality and mycoflora is complicated by the lack of appropriate indicators for air quality and by the occurrence of wide spatial and temporal changes in diversity and compositions among samples.
  • Jayaprakash, Balamuralikrishna; Adams, Rachel I.; Kirjavainen, Pirkka; Karvonen, Anne; Vepsalainen, Asko; Valkonen, Maria; Jarvi, Kati; Sulyok, Michael; Pekkanen, Juha; Hyvarinen, Anne; Taubel, Martin (2017)
    Background: The limited understanding of microbial characteristics in moisture-damaged buildings impedes efforts to clarify which adverse health effects in the occupants are associated with the damage and to develop effective building intervention strategies. The objectives of this current study were (i) to characterize fungal and bacterial microbiota in house dust of severely moisture-damaged residences, (ii) to identify microbial taxa associated with moisture damage renovations, and (iii) to test whether the associations between the identified taxa and moisture damage are replicable in another cohort of homes. We applied bacterial 16S rRNA gene and fungal ITS amplicon sequencing complemented with quantitative PCR and chemical-analytical approaches to samples of house dust, and also performed traditional cultivation of bacteria and fungi from building material samples. Results: Active microbial growth on building materials had significant though small influence on the house dust bacterial and fungal communities. Moisture damage interventions-including actual renovation of damaged homes and cases where families moved to another home-had only a subtle effect on bacterial community structure, seen as shifts in abundance weighted bacterial profiles after intervention. While bacterial and fungal species richness were reduced in homes that were renovated, they were not reduced for families that moved houses. Using different discriminant analysis tools, we were able identify taxa that were significantly reduced in relative abundance during renovation of moisture damage. For bacteria, the majority of candidates belonged to different families within the Actinomycetales order. Results for fungi were overall less consistent. A replication study in approximately 400 homes highlighted some of the identified taxa, confirming associations with observations of moisture damage and mold. Conclusions: The present study is one of the first studies to analyze changes in microbiota due to moisture damage interventions using high-throughput sequencing. Our results suggest that effects of moisture damage and moisture damage interventions may appear as changes in the abundance of individual, less common, and especially bacterial taxa, rather than in overall community structure.
  • Nissilä, Juho-Jooel; Savelieva, Kateryna; Lampi, Jussi; Ung-Lanki, Sari; Elovainio, Marko; Pekkanen, Juha (2019)
    Poor indoor air quality (IAQ) in schools is related to increased symptom reporting in students. We investigated whether parental worry about school IAQ influences this association. Data came from survey collected from five Finnish primary schools with observed IAQ problems and five control schools. Parents (n = 1868) of primary school students reported worry about IAQ in schools and symptoms of their children. Associations between observed IAQ problems, worry, and five symptom scores (ie, respiratory, lower respiratory, eye, skin, and general symptoms) were analyzed using multivariate logistic regression and mediation analysis. Parents were on average more worried in schools with observed IAQ problems. Observed IAQ problems were strongly associated with increased worry and all symptoms under study (unadjusted ORs ranged between 1.48 [95% CI 1.48-2.16] and 2.70 [95% CI 1.52-5.17]). Parental worry was associated with all symptoms (unadjusted ORs ranged between 2.49 [95% CI 1.75-3.60] and 4.92 [95% CI 2.77-9.40]). Mediation analyses suggested that parental worry might partially explain the association between observed IAQ problems and symptom reporting (proportion mediated ranged between 67% and 84% for the different symptoms). However, prospective studies are needed to assess causal relationships between observed IAQ problems, worry, and symptom reporting in schools.
  • Tähtinen, Katja; Remes, Jouko; Karvala, Kirsi; Salmi, Kari; Lahtinen, Marjaana; Reijula, Kari (2020)
    Objectives: The study examined the extent and prevalence of perceived indoor environment-related (IE-related) symptoms environmental complaints and psychosocial work environmental factors in Finnish office, school and health care environments. Material and Methods: The data were collected from non-industrial workplaces (N = 455) in 2011-2012 and 2015-2017 using the Finnish Institute of Occupational Health's Indoor Air Questionnaire (IA Questionnaire). Suspicion of IE-related problems was reported in 59% of workplaces. The data consisted of 28 826 employees' responses. Results: The employees reported symptoms and environmental discomfort in office environments less often than in school or health care environments. The most often reported IE-related complaints were stuffy air (39% of respondents), dry air (34%) and insufficient ventilation (33%). The most often reported symptoms were irritation of the nose (27% of respondents), irritation of the eyes (26%), and hoarse or dry throat (24%). The results showed differences between the perceived IE in office, school and health care environments. Conclusions: Compared to earlier findings, the most often perceived IE-related symptoms and complaints have increased in Finnish health care environments. The office employees' perceptions of psychosocial work environment remained fairly unchanged whereas health care personnel more often assessed their psychosocial environment as positive compared to previous reports. Instead of exact reference values, comparing the results of IA Questionnaires with the distributions and mean values of the results of this study may be more informative for those striving to solve IE-related problems. The presented distribution and mean values of perceived symptoms, environmental complaints and psychosocial work environment might help to relate the results to other workplaces. This, in turn, might increase the understanding that IA Questionnaire results are influenced by many factors. The results presented can be used as new reference material when interpreting the results of IA Questionnaires in office, school and health care environments.