Dust of grains and malts as a source of ochratoxin A exposure.

Ochratoxin A (OTA) was found more frequently and in higher concentrations (range 0.05-9.9 µg/kg) in dust samples than in corresponding samples of barley (n=23) and malt (n=9), which contained only trace amounts. Feed pellets and meals, prepared out of malt rootlets and dust fractions, contained OTA up to 6.01 µg/kg. Serum samples from seven malt factory workers showed OTA levels between 0.13 and 2.6 ng/ml. Higher levels in autum (median 0.58 ng/ml) than in summer (median 0.34 ng/ml) indicate that handling of barley in past-harvest time and an increased exposure to dusts might be responsible for these findings.