Effect of environmental heavy metals on the expression of detoxification-related genes in honey bee Apis mellifera

Air pollutants and agricultural pesticides can be environmental stressors to pollinators. In this study, to investigate the expression of detoxification-related genes and heavy metal concentrations in honey bees and honey possibly exposed to environmental stresses, we collected samples from apiaries located in mountainous, agricultural, and urban areas. Compared with the mountainous and agricultural areas, the mercury and lead concentrations were highest in honey and bees collected from urban areas. In addition, the expression levels of CYP9Q1, CYP9Q2, CYP9Q3, and genes encoding catalase and superoxide dismutase were markedly higher in urban bees than those from agricultural and mountainous areas, discreetly indicating that the notable induction of the detoxification metabolism in urban bees might be because of heavy metal pollutant exposure. Our study suggests that honey bees actively respond to environmental stressors, such as heavy metals derived from urban areas.