In organic waste treatment facilities, bioaerosols containing microorganisms (e.g., bacteria, fungi) as well as biomolecules (e.g., debris from membranes, mycotoxins) are released during the movement of material. We conducted a human biomonitoring study to investigate the possible occupational exposure of workers to mycotoxins. In total, 50 workers from three organic waste treatment facilities in Germany and 37 volunteers without expected occupational exposure to moulds provided spot urine samples. These were analysed for the presence of ten urinary mycotoxin biomarkers using liquid chromatography with tandem mass spectrometry.Deoxynivalenol (DON) was detected in nearly all (96%) of the samples of workers and controls followed by deepoxy-deoxynivalenol (21%) and ochratoxin A (OTA, 16%). Aflatoxins, gliotoxin and ochratoxin alpha could not be detected in any of the samples.Total DON concentrations in post-shift samples of workers were significantly higher than those observe in samples of controls (medians 2.94 vs. 1.69 μg/g creatinine). Additionally, total DON concentrations increased over the working shift. No exceedance of the tolerable daily DON intake was observed. Thus, the results point to an occupational exposure to DON that is unlikely to pose a health risk.Contrary, urinary OTA levels reveal no differences between workers and controls, and thus, mainly reflect the dietary background exposure.

This article is published in the "International Journal of Hygiene and Environmental Health" (2026).