Table 23.
Summary of qualitative evaluation of the impact of uncertainties on the risk assessment of the human and animal dietary exposure to DAS
| Sources of uncertainty | Directiona |
|---|---|
| Extrapolation of the occurrence data to the whole of Europe | +/− |
| Consumption data: different methodologies/representativeness/underreporting/misreporting/no portion size standard | +/− |
| Assuming non‐targeted sampling for literature data used for exposure | + |
| Uncertainty of the analytical measurements | +/− |
| No data for most grain based products and other foods and no data on other feed than grains | − |
| High variability of the composition of feedstuffs used and feeding systems for farm animals in Europe | +/− |
| High percentage of left censored data resulting in large difference between LB and UB exposure estimates | +/− |
| Highest reliable percentile limited by the number of samples | − |
| Lack of data on general toxicity and reproductive and developmental toxicity in experimental and most farm and companion animals | +/− |
| Limited data on the mode of action | +/− |
| Lack of data to asses genotoxicity and carcinogenicity | − |
| Assumption of equivalent exposure and toxicity effects after i.v. and oral administration of the same dose | + |
| Use of large adjustment factors for risk assessment (humans) | + |
| Co‐exposure and potential combined effects of DAS and other trichothecenes | − |
a
+ = uncertainty with potential to cause over‐estimation of exposure/risk; − = uncertainty with potential to cause under‐estimation of exposure/risk.