ASSESSING AIRBORNE AFLATOXIN B-1 DURING ON FARM GRAIN HANDLING ACTIVITIES

The presence of aflatoxin in corn and corn dust during relatively norm al years and the increased risk of Aspergillus flavus infestation duri ng drought conditions suggest that airborne agricultural exposures sho uld be of considerable concern. Liquid extraction, thin layer chromato graphy, and high pressure liquid chromatography were used for the anal ysis of aflatoxin B-1 in grain dust and bulk corn samples, A total of 24 samples of airborne dust were collected from 8 harms during harvest , 22 samples from 9 farms during animal feeding, and 14 sets of Anders en samples from 11 farms during bin cleaning. A total of 14 samples of settled dust and 18 samples of bulk corn were also collected and anal yzed. The airborne concentration of aflatoxin B-1 bound in dust collec ted during harvest and grain unloading ranged from 0.04 to 92 ng/m(3). Higher levels of aflatoxin B-1 were found in the airborne dust sample s collected from enclosed animal feeding buildings (5-421 ng/m(3)) and during bin cleaning (124-4849 ng/m(3)), Aflatoxin B-1 up to 5100 ng/g were detected in settled dust collected from an enclosed animal feedi ng building; however, no apparent correlation was found between the ai rborne concentration of aflatoxin B-1 and its concentration in settled dust or bulk corn. The data demonstrate that farmers and farm workers may be exposed to potentially hazardous concentrations of aflatoxin B -1, particularly during bin cleaning and animal feeding in enclosed bu ildings.