Browsing by Subject "Moisture damage"

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  • Jayaprakash, Balamuralikrishna; Adams, Rachel I; Kirjavainen, Pirkka; Karvonen, Anne; Vepsäläinen, Asko; Valkonen, Maria; Järvi, Kati; Sulyok, Michael; Pekkanen, Juha; Hyvärinen, Anne; Täubel, Martin (BioMed Central, 2017)
    Abstract 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.
  • 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.
  • Kirjavainen, P. V.; Taubel, M.; Karvonen, A. M.; Sulyok, M.; Tiittanen, P.; Krska, R.; Hyvarinen, A.; Pekkanen, J. (2016)
    We aimed to characterize the presence of microbial secondary metabolites in homes and their association with moisture damage, mold, and asthma development. Living room floor dust was analyzed by LC-MS/MS for 333 secondary metabolites from 93 homes of 1-year-old children. Moisture damage was present in 15 living rooms. At 6 years, 8 children had active and 15 lifetime doctor-diagnosed asthma. The median number of different metabolites per house was 17 ( range 8-29) and median sum load 65 ( 4-865) ng/m(2). Overall 42 different metabolites were detected. The number of metabolites present tended to be higher in homes with mold odor or moisture damage. The higher sum loads and number of metabolites with loads over 10 ng/m(2) were associated with lower prevalence of active asthma at 6 years ( aOR 0.06 ( 95% CI <0.001-0.96) and 0.05 (<0.001-0.56), respectively). None of the individual metabolites, which presence tended ( P <0.2) to be increased by moisture damage or mold, were associated with increased risk of asthma. Microbial secondary metabolites are ubiquitously present in home floor dust. Moisture damage and mold tend to increase their numbers and amount. There was no evidence indicating that the secondary metabolites determined would explain the association between moisture damage, mold, and the development of asthma.
  • Harmo, Panu; Puusa, Janne; Lehtinen, Simo; Selkäinaho, Jorma; Aattela, Elisa; Visala, Arto; Salkinoja-Salonen, Mirja Sinikka; Työryhmä: Sisäilmapoliisi (Siy sisäilmatieto oy, 2017)
    SIY Raportti
    Rikkivety tiedetään terveydelle haitalliseksi kroonisessa tai usein toistuvassa altistuksessa jo alle 0,01 mg/m3 pitoisuuksissa, mutta sen monitorointiin markkinoiden kenttäkelpoisten mittarien herkkyys (≥0,05 mg/m3) ei riitä. Kehitimme online-luettavan hopeaanturin sulfidikaasujen havainnointiin sisätiloissa, joissa on tarvetta matalien pitoisuuksien pitkäaikaisseurantaan. Mittausanturi on pienikokoinen, äänetön, kustannustehokas eikä häiritse tilojen muuta toimintaa. Useita antureita samanaikaisesti 24/7 käyttäen on mahdollista jäljittää sulfidikaasujen päästölähteet ja purkautumisajankohdat koko kiinteistössä. Anturin herkkyydeksi osoittautui 0,002 mg kertapurkaus sulfidirikkiä, mutta pienemmätkin yksittäispäästöt tulivat näkyviin, jos purkauksia oli useita. Antureiden sijoittamista vaihtelemalla on mahdollista paikantaa sulfidikaasujen päästölähteet.