The condition of the bee colony (Apis mellifera) after exposure to pesticide and their mixtures

Abstract In the natural environment, bees are often exposed to low concentrations of pesticide mixtures while foraging. These substances can be carried back to the hive, threatening the health and life of the entire colony. For seven consecutive days, honey bee workers were fed daily with 0.5 L of sugar syrup containing a commercial formulation of acetamiprid, glyphosate, and tebuconazole, administered either individually or in two- or three-component mixtures The feed was both actively consumed by the bee colonies and stored in the combs. As a result, their exposure to the pesticides was chronic and lasted until the stored feed was fully consumed before the onset of winter. Pesticide concentrations in the syrup reflected environmental residue levels: 250 ppb for acetamiprid, 7200 ppb for glyphosate, and 147 ppb for tebuconazole. The study aims to assess the impact of these pesticides on colony health, focusing on colony size, brood, and food reserves. No statistically significant differences were found between the groups. Despite the results showing no negative effects of acetamiprid, glyphosate, and tebuconazole on the parameters studied, pesticides still pose a major risk to bees, which may contribute to a decline in their population and consequently in environmental biodiversity. Future research should focus on using acetamiprid, glyphosate, and tebuconazole, but in combination with other commonly used pesticides. The potential risks of unresearched mixtures should be investigated.