Concentration and determinants of molds and allergens in indoor air and house dust of French dwellings

Abstract

Molds and allergens are common indoor biocontaminants. The aims of this study were to assess the concentrations of common molds in indoor air and floor dust and the concentrations of house dust mite, cat and dog allergens in mattress dust in French dwellings, and to assess predictors of these concentrations. A sample of 150 houses in Brittany (western France) was investigated.Airborne Cladosporium and Penicillium were detected in more than 90% of the dwellings, Aspergillus in 46% and Alternaria in only 6% of the housings. Regarding floor dust samples, Cladosporium and Penicillium were detected in 92 and 80% of the housings respectively, Aspergillus in 49% and Alternaria in 14%. House dust mite allergens Der p1 and Der f1 were detected in 90% and 77% of the mattress dust samples respectively and Can f1 and Fel d1 in 37% and 89% of the homes. Airborne and dustborne mold concentrations, although not statistically correlated (except for Aspergillus) shared most of their predictors. Multivariate linear models for mold levels, explaining up to 62% of the variability, showed an influence of the season, of the age of the dwelling, of aeration habits, presence of pets, smoking, signals of dampness, temperature and relative humidity. Allergens in the dust of the mattress were strongly related to the presence of pets and cleaning practices of bedsheets, these factors accounting for 60% of the variability. This study highlights ubiquitous contamination by molds and underlines complex interaction between outdoor and indoor sources and factors.3

Exposure to Indoor Allergens in Different Residential Settings and Its Influence on IgE Sensitization in a Geographically Confined Austrian Cohort

“…Although reported household cleanliness in our study considered the frequency of changing bedsheets, we could not confirm results of a French study reporting an increased Der f 1 amount when changing bedsheets less often [59]. We found, however, slight positive correlations between household cleanliness and IgE levels to mite allergens.…”

Indoor gaseous air pollutants determinants in office buildings—The OFFICAIR project

“…The variables having more than 40% of missing data, zero‐variance variables (variables where all individuals presented the same modality), and near zero‐variance variables (variables where only one individual presented a different modality than the rest of the sample) were removed. Variables with unbalanced class distribution (classes with < 10% of cases) were also excluded . The air change rate of the office rooms (h −1 ) obtained from PFT measurement was missing in 43% of cases (while airflow measurement were missing for almost all the office building); however, due to its well‐known impact on indoor air quality, missing data were assigned by the statistical multiple imputation method .…”

“…A pre‐analysis study was carried out to guarantee that determinants have a real effect on IAPs concentrations if included in models with other predictors. So, each possible predictor of IAPs concentrations was individually tested by univariate linear mixed models for repeated measurements were beforehand run for every variable . The cut‐off P value ≤ 0.001 was chosen for inclusion in the models with other predictors.…”

“…So, each possible predictor of IAPs concentrations was individually tested by univariate linear mixed models for repeated measurements were beforehand run for every variable. 37 The cut-off P value ≤ 0.001 was chosen for inclusion in the models with other predictors. Multideterminant models were constructed by both backward and forward approaches with non-inter-associated determinants, with a significant level set at P < .01.…”

House dust fungal communities’ characterization: a double take on the six by sixty by six (6 × 60 × 6) project

“…This matrix results essentially from materials tracked indoors and the settling of airborne particles, a process that can take weeks or even months (especially the latter), being therefore regarded as a timeintegrated sample [8,9]. Furthermore, house dust is an easy sample to obtain and its use in epidemiological studies on human exposure to environmental contaminants, has been highly recommended [10,11].…”