Survey of 1012 moldy dwellings by culture fungal analysis: Threshold proposal for asthmatic patient management

Abstract

Different countries have tried to define guidelines to quantify what levels of fungi are considered as inappropriate for housing. This retrospective study analyzes indoor fungi by cultures of airborne samples from 1012 dwellings. Altogether, 908 patients suffering from rhinitis, conjunctivitis, and asthma were compared to 104 controls free of allergies. Portuguese decree law no 118/2013 (PDL118), ANSES (a French environmental and health agency) recommendations, and health regulations of Besançon University Hospital were applied to determine the rates of non‐conforming dwellings, which were respectively 55.2%, 5.2%, and 19%. Environmental microbiological results and medical data were compared. The whole number of colonies per cubic meter of air was correlated with asthma (P < 0.001) and rhinitis (P = 0.002). Sixty‐seven genera and species were detected in bedrooms. Asthma was correlated to Aspergillus versicolor (P = 0.004) and Cladosporium spp. (P = 0.02). Thresholds of 300 cfu/m3 for A. versicolor or 495 cfu/m3 for Cladosporium spp. are able to discriminate 90% of the asthmatic dwellings. We propose a new protocol to obtain an optimal cost for indoor fungi surveys, excluding surface analyses, and a new guideline to interpret the results based on >1000 cfu/m3 of whole colonies and/or above threshold levels for A. versicolor or Cladosporium spp.

House characteristics and condition as determinants of visible mold and musty odor: Results from three New Zealand House Condition Surveys in 2005, 2010, and 2015

“…Associations with rental tenure cannot be explained by BEC, insulation and ventilation as analyses were controlled for these factors. However, as shown previously using the same survey data, 25,27 rental homes are more likely to have higher occupant density, which may contribute to the higher risk of indoor mold as demonstrated in other studies for both visible mold 17 and airborne fungi 35 . Information for floor area was available for 2005 and 2010, and a ratio of occupants to floor area was calculated for these two surveys.…”

“…However, as shown previously using the same survey data, 25,27 rental homes are more likely to have higher occupant density, which may contribute to the higher risk of indoor mold as demonstrated in other studies for both visible mold 17 and airborne fungi. 35 Information for floor area was available for 2005 and 2010, and a ratio of occupants to floor area was calculated for these two surveys. This ratio was significantly associated with mold in the whole house, and to a lesser degree mold in living and bedrooms, but not musty odor (data not shown).…”

Fungal Contaminants in Energy Efficient Dwellings: Impact of Ventilation Type and Level of Urbanization

“…The most common genera isolated in settled dust were Cladosporium, Penicillium, and Aspergillus Their presence in indoor environments was commonly reported in a large number of studies [ 55 , 56 ], in particular in traditional dwellings bordering a French area [ 57 ]. As a high number of spores per unit area (e.g., 10 2 to 10 3 CFU/cm 2 ) can become aerosolized from natural building materials in homes [ 58 ], residents who sleep near a mouldy area can be exposed to relatively high concentrations of fungal particles.…”

Association between indoor formaldehyde exposure and asthma: A systematic review and meta‐analysis of observational studies

“…5,6 Accumulating evidence shows that indoor environmental pollutants, such as respirable particles, pollen, mold, and house dust-mites, play important roles in the progression and occurrence of asthma, as 90% of human activities take place in the indoor environment (eg, home, classroom, and workplace). [7][8][9][10][11] In the indoor environment, the concentration of formaldehyde (FA), which is a ubiquitous human carcinogenic (group 1) mainly released from tobacco smoke and…”