Mould and mycotoxin are not equivalent
Not all moulds produce mycotoxins, and a species does not produce them under every condition. Strain, temperature, moisture and substrate matter. Visible mould alone does not establish which toxin is present or at what concentration. Aflatoxins, ochratoxin A and deoxynivalenol are different examples; they do not necessarily have the same effects and should not be assigned one universal toxicity or interpreted as interchangeable findings.
Activities that deserve attention
Handling cereals, animal feed, spices and other organic materials can disturb contaminated dust. Some composting, waste-treatment and laboratory operations are also relevant. Review receipt, unloading, cleaning and maintenance as well as normal production. Bioaerosol assessment should consider the actual material and its history rather than assuming identical contamination in every batch. Less frequent dusty tasks can be important even where routine production is enclosed.
Known hazards and remaining uncertainty
Substantial toxicological knowledge exists for some mycotoxins, particularly through food exposure. Evidence on effects from occupational inhalation or skin exposure is more limited. This supports reducing exposure without claiming that any detected amount causes a particular disease. Food limits cannot be directly converted into workplace-air limits: route, dose and the purpose of the criterion differ. Conclusions should separate established toxicological hazards from evidence about the particular workplace situation.
Measure the toxin of interest
Fungal counts and dust mass do not replace specific mycotoxin analysis. The laboratory needs to know the target analytes and sample type. INRS provides methods for several toxins, but a panel does not automatically represent every possible compound. Record tasks, batches, storage, duration and other exposures. Experimental biological measurements are not a universal clinical test for occupational poisoning and should not be interpreted as such without specialist assessment.
Control the material and dust
Measures include preventing storage conditions favourable to mould and reducing emissions during handling. Enclosure, capture and cleaning that avoids dust resuspension are relevant choices. Verify improvements during actual work and include cleaning and maintenance personnel. Symptoms warrant professional health assessment supported by exposure information; suspected mycotoxicosis cannot be diagnosed simply because a building is damp. The practical objective is to reduce exposure while investigating the specific source and circumstances.
Where a report identifies a toxin in stored material, the next question is how it could reach workers during their task. A product result helps guide investigation but is not a breathing-zone concentration. Keeping these questions separate supports relevant sampling and avoids conclusions about occupational exposure that has not actually been measured or characterised.
