*2.7. Bee Health Risk Assessment*

The risk assessment for bees was based on EFSA's bee guidance document [24] and the published risk assessment procedure by Sanchez-Bayo and Goka [25]. LD50 values for pesticides were retrieved from EFSA's publications on active substances and the Pesticide Properties Database of the University of Hertfordshire [26].

To address the subsequent risk to bees due to the consumption of contaminated pollen, the standard risk approach was followed, taking into account EFSA's bee guidance document [24] and a pertinent published work [25]. To determine the risk, the following equation was followed:

$$Risk = F\left(\%\right) \times \frac{dose}{LD50} \tag{4}$$

where *F*: the % detection frequency of the active substance in samples; *dose*: is the daily dose in μg per bee, considering pollen's daily consumption by bees (maximum consumption as a worst-case scenario) and concentration (average and maximum) obtained in this work; *LD*50: median lethal dose per bee (oral and contact, in μg per bee). The frequency of detection is essential since it depicts, as mentioned by previous research group [25], the probability of exposure of bees to the determined pollutants.
