Exposure assessment to mycotoxins in workplaces: Aflatoxins and ochratoxin A occurrence in airborne dusts and human sera

In order to evaluate the possible presence of mycotoxins in airborne particulates, a micro-method by HPLC was performed for aflatoxins and ochratoxin A (OA) in dust samples. A total of 44 samples of airborne particulates were collected in three different workplaces in Tuscany (central Italy), where three of the most susceptible foodstuffs (cocoa, coffee and spices) are processed. Air samples were obtained through both area and personal samplings collected during the entire workshift. Whenever possible, workers' sera were collected in order to check the biomarker of exposure for OA. Dust samples were contaminated at different levels, ranging from less than the limit of detection to 0.080 ng for aflatoxins and to 5.481 ng for OA. The wide range of toxin levels could be related to different causes, such as the distance between the worker and the stocked raw materials, the worker's job, the exposure time and the amount of particulate matter sampled. Airborne levels of OA, and aflatoxins B1, B2, G1 and G2 were in the range 0.001-8.304, <0.002-0.038, <0.002-0.029, <0.002-0.036 and <0.014-0.131 ng/m3, respectively. OA levels in workers' sera showed much higher results (0.94-3.28 ng OA/ml) than the mean level found in the Italian population, showing that inhalation in the workplace can be considered a route of exposure additional to the consumption of contaminated foodstuffs