This article describes a practical method for detecting the presence of both fungal spores and culturable fungi in wall cavities. Culturable fungi were collected in 25 mm cassettes containing 0.8 microm mixed cellulose ester filters using aggressive sampling conditions. Both culturable fungi and fungal spores were collected in modified slotted-disk cassettes. The sample volume was 4 L. The filters were examined microscopically and dilution plated onto multiple culture media. Collecting airborne samples in filter cassettes was an effective method for assessing wall cavities for fungal contaminants, especially because this method allowed the sample to be analyzed by both microscopy and culture media. Assessment criteria were developed that allowed the sample results to be used to classify wall cavities as either uncontaminated or contaminated. As a criterion, wall cavities with concentrations of culturable fungi below the limit of detection (LOD) were classified as uncontaminated, whereas those cavities with detectable concentrations of culturable fungi were classified as contaminated. A total of 150 wall cavities was sampled as part of a field project. The concentrations of culturable fungi were below the LOD in 34% of the samples, whereas Aspergillus and/or Penicillium were the only fungal genera detected in 69% of the samples in which culturable fungi were detected. Spore counting resulted in the detection of Stachybotrys-like spores in 25% of the samples that were analyzed, whereas Stachybotrys chartarum colonies were only detected on 2% of malt extract agar plates and on 6% of corn meal agar plates.
A microvacuum method is described for sampling fungal contaminants in carpet dust and reporting the results on an area basis. When sampling parameters such as suction force, contact time, and area sampled were held constant, and the results were reported on an area basis, fungal concentrations were associated with the potential for water intrusion, a determinant of exposure. Carpet dust samples were collected in open-face 25-mm cassettes containing 0.8 micro m mixed cellulose ester filters. The airflow rate was calibrated at 10 L/min, and the open-faced cassette was held firmly against the carpet at 20 separate spots for a period of 5 sec at each spot. An area of 98 cm(2) of carpet was sampled with each cassette. A total of 58 carpet dust samples were collected in 31 residential condominium units using the described methodology. The carpets were stratified into three groups: (1) controls and those at centers of rooms, (2) at sliding glass doors and under windows, and (3) in areas of water intrusion reported by the occupant. The geometric mean concentrations (GM) of total fungi increased in the listed order, as did the GM concentrations of Penicillium spp. and Aspergillus spp. detected in the samples. In addition, the 95% confidence intervals on the GM concentrations for total fungi could be used to classify the carpets into three groups: uncontaminated, potentially contaminated, and contaminated.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.