Inhalable Exposure Levels of Airborne Mold spores in Rural Georgia Homes

Exposure to mold is known to cause allergic symptoms. Most molds produce highly allergenic proteins or glycoproteins that can cause hypersensitivity diseases in susceptible hosts. Between 10% and 60% of genetically susceptible persons develop immediate hypersensitivity to mold. The Institute of Medicine report on Damp Indoor Spaces and Health states that there is sufficient evidence to conclude that a causal relationship exists between the presence of mold and upper respiratory tract symptoms, cough, hypersensitivity pneumonitis in susceptible persons, wheeze, and asthma symptoms in sensitized asthmatic persons. To our knowledge, no research has been conducted in rural Georgia to test the air quality indoors, particularly with respect to mold. Therefore, within Statesboro, Georgia area, 8 different homes have been visited to see the air quality within the household. In the homes, an air sampling pump was set for a 48 hour time period and indoor air samples were collected using an inhalable aerosol sampler which can effectively collect mold spores of up to 100 åµm aerodynamic diameter. In addition, at each study site, the temperature, moisture and humidity levels were measured. A questionnaire was given to each subject about their previous to present respiratory status and their basic demographics. Mixed cellulose ester membrane filters were used for collecting spores in the inhalable aerosol sampler. The filters were cleared with acetone vapor, stained by lactophenol and cotton blue, and examined under a high-resolution light microscope at 400X magnification. Mold spores were identified and total spore counts were converted to airborne inhalable spore concentrations. Preliminary data showed that total spore concentration ranged from 427 to 1,994 spores/m3 and most common spore types were Aspergillus/Penicillium, Ascospores, Cladosporium, Curvularia, Periconia, Smuts/Myxomycete, and unknown species. Several species of Aspergillus, Penicillium, Cladosporium, and Curvularia were previously reported to be allergic for humans sensitive to mold allergens.