Mycotoxins are a quite numerous group of substances released as metabolites by molds, which badly affect human and animal health. Their impact on organisms resulting from alimentary exposure is well recognized, but the mechanisms by which they exert their health effects after inhalation exposure are still poorly investigated. The aim of this work was to review the literature concerning the outcomes of occupational exposure to mycotoxins present in the work environment. The author discusses the major mycotoxin classes, their chemical structure, some physicochemical properties and biological activity properties. This paper summarizes the results of investigations on the impact of occupational exposure to molds present in the workplace air in various branches of industry. Problems of identifying the mechanism of health effects exerted due inhalation exposure to mycotoxins are also discussed. This review shows that there is lack of good hygiene standards and legislation regulating the presence of these compounds in the workplace air. These is due to insufficient number of analyses aimed at estimating short-term inhalation exposure to mycotoxins and lack of monitoring of long-term exposure and its health effects. The authors concludes that occupational exposure to mycotoxins and their role in the development of pathological changes in the respiratory system require further investigations. Med Pr 2008;59(4):333-345