Sperm comet assay as a novel tool in assessing genotoxicity in high-mortality honey bee (Apis mellifera) populations

The recent increase in mortality rates amongst honey bee colonies is a cause for concern. Assessing DNA damage in reproductive cells is crucial for species survival. This study aims to evaluate the potential of the sperm comet assay as a tool for in situ assessment of the genotoxic impact on honey bee populations with established high mortality rates. Previous studies have identified the presence of pesticide residues in bees and food stocks within the hives, indicating the existence of genotoxic agents in the localities under investigation. The values of comet assay parameters, namely Tail Intensity (TI%) and Olive Tail Moment (OTM, µm), scored in the sperm cells, increased following the mortality trend of the honey bee populations under study, providing evidence of significant DNA damage occurring during spermatogenesis. The alkaline comet assay in hemolymph confirmed the genotoxic effects observed in the sperm comet assay. The current study demonstrated for the first time that the sperm comet assay could serve as a reliable novel method for assessing genotoxicity in A. mellifera.