Increase in tumour necrosis factor-alpha and a change in the lactate dehydrogenase isoenzyme pattern in plasma of workers exposed to aflatoxin-contaminated feeds.

Six types of animal-feed ingredients and swine mixed feeds from factories in northern Thailand were sampled for analysis of mycotoxins. Mycotoxins found in foodstuffs included aflatoxins, fumonisins, ochratoxins, T-2 toxin, vomitoxin and zearalenone. Samples of airborne dust generated while handling animal feed were collected and analysed to assess exposure of workers to aflatoxins. The average aflatoxin level in the control air samples was 0.99 ng/m3. Higher levels of aflatoxins were found in the air samples taken by samplers attached to five workers adding hydrated sodium calcium aluminosilicate to animal feed (group 1; 1.55 ng/m3) and five workers adding glucomannan to animal feed (group 2; 6.25 ng/m3). The exposed workers showed a change in lactate dehydrogenase isoenzyme activity and tumor necrosis factor-levels in plasma. These changes may be associated with inhalation of mycotoxins and other contaminants in foodstuff. Occupational exposure to mycotoxins and mycotoxin adsorbents needs further evaluation in order to set up a proper system for long term surveillance of exposed population.