Evaluation of respiratory symptoms and their possible association with residential indoor bioaerosol concentrations and other environmental influences.

The study discussed here evaluated the presence of self-reported respiratory symptoms and their association with indoor bioaerosol concentrations over a year-long study in the El Paso, Texas, region. The authors collected air samples from homes to assess seasonal differences in bacterial and fungal bioaerosol concentrations. They distributed a health questionnaire to the participating homeowner during each seasonal air sampling. The authors used this questionnaire to assess whether the homeowners were suffering from specific symptoms prior to each sampling. Descriptive statistics and logistic regressions were conducted to model the relationship among "high" reporters of symptoms, bioaerosols, and environmental factors. The authors collected evidence to support an association between indoor respirable bacterial concentrations and homeowners that reported at least eight respiratory symptoms (odds ratio [OR] = 1.10, p = .045). Smoking status, indoor humidity, and season also displayed associations with homeowners that reported at least eight respiratory symptoms (current smokers OR = 3.3, p = .042; indoor humidity OR = 1.5, p = .030; spring season OR = 7.2, p = .001; fall season OR = 3.4, p = .008).

Seasonal fine and coarse culturable fungal constituents and concentrations from indoor and outdoor air samples taken from an arid environment.

This study was undertaken to determine the normal indoor and outdoor airborne culturable fungal constituents and concentrations of an arid environment. Air samples were taken with two-stage, ambient, culturable sampler systems and analyzed for nine specific fungal genera from 50 homes as a repeated measure during each season of the year. These homes had no previous histories of indoor air quality issues. This study detected seasonal differences for the arid environment between different culturable fungal concentrations across the two size ranges. The highest concentrations were during fall, in the outdoor fine-size range. The lowest concentrations were the indoor coarse concentrations in the spring. From this study it can be concluded that Cladosporium spp. had the highest concentrations during fall in an arid environment. The overall findings suggest that Cladosporium had concentrations greater than the other genera evaluated, specifically, the fall outdoor fine concentrations. Seasonality was found to be a key factor in determining the variability of fungal constituents and concentrations within the arid indoor and outdoor environments. The fine-size range was 12 times and 6 times greater than the coarse-size range for indoor and outdoor samples, respectively, which accounted for the majority of fungal organisms. In addition, the results from this study in an arid climate differ from those conducted in a moister climate.