Genotoxic effect of two environmentally safe doses of cadmium on the hepato-nephrocytic system of Bombus atratus forager workers

Abstract

Eusocial bees are declining due to anthropogenic actions. Individuals can be exposed to contaminants like Cd, which have been found in pollen. Thus, we evaluated the potential genotoxicity of Cd to the hepato-nephrocitic system of Bombus atratus foraging workers exposed to environmentally safe doses of Cd (0.001 mg/kg and 0.003 mg/kg) during 72 h. To assess the genotoxicity of Cd, we conducted an alkaline comet assay. Doses of 0.001 mg/kg of Cd caused comets of levels 2 and 3, and 0.003 mg/kg of Cd induced comets of level 4, while controls exhibited regular nucleoids. Also, 0.003 mg/kg doses caused higher Damage Index, Damage Frequency, and Total Damage. Our results bring new evidence that 0.003 mg/kg Cd exerted genotoxicity to the HNS cells of B. atratus, probably affecting secondary metabolism and the detoxification capability of bees.

Keywords: Bumblebees; DNA toxicity; Ecotoxicity; Trace metals.