Size range of viable fungal particles from aflatoxin-contaminated corn aerosols.
Sorenson-WG; Peach-MJ III; Simpson-JP; Olenchock-SA; Taylor-G
Occupational Pulmonary Disease. Focus on Grain Dust and Health 1980 jan; :527-536
Size range of viable fungi particles from aflatoxin (1402682) contaminated corn aerosols was studied in 12 samples of Georgia corn. The samples represented four categories of aflatoxin content (0 to 20, 20 to 200, 200 to 400, and 400 to 800 parts per billion (ppb)). The apparatus used for sampling consisted of an aerosol generator, an aerosol chamber, and an Andersen sampler. The sampler was employed because of its simulation of the human respiratory system. Incidence of the fungus Aspergillus-flavus (A-flavus) was compared in each sample on an individual kernel basis employing the method of Fennell et al. After 10 minutes of air wash there were only a small percentage of the viable particles in the original aerosol remaining. The results were the same whether the plates were counted at 72 hours or after 5 days incubation at 30 degrees-C. Analysis of covariance was used to study the relationship between total colony counts and sampling time interval. A significant linear relationship was observed between sampling time interval and total colony counts after correcting for the effect of different corn samples. Total colony counts for each stage of the sampler for each corn sample were listed. Few fungal particles were observed on plates from the fifth and sixth stages of the sampler (less than 2.1 micrometers (microm)) and 94.2 percent of the viable particles were equal to or greater than 3.3microm. Particle size distribution of the major organisms was also listed. A-flavus was the dominant organism (100 percent of samples) representing 82.9 percent of the total colonies observed; a significant proportion of colonies arose from particles less than 5microm. The results suggested that workers subjected to grain dust containing high levels of A-flavus conidia might be at risk. At least four different Penicillium species were observed. Incidence of A-flavus on kernels in relation to aflatoxin content was listed. The results showed a striking correlation between incidence of A-flavus and aflatoxin content.
Occupational-exposure; Grain-dusts; Aerosol-sampling; Aerosol-particles; Fungi; Pulmonary-system-disorders; Agricultural-workers; Dust-analysis; Toxins
Book or book chapter
Occupational Pulmonary Disease. Focus on Grain Dust and Health