Exploring the potential of three species of blowfly, genus Chrysomya, as bioindicators of heavy metals in the Brazilian Cerrado savanna

Inadequate and unregulated disposal of agricultural and commercial residues represents a significant challenge for the management of environmental impacts. The inadequate disposal of this waste can lead to the accumulation of high concentrations of heavy metals, including cadmium, chromium, lead, manganese, and zinc, in the soil. Many insects are excellent bioindicators of environmental contamination, although their capacity for the superficial bioaccumulation of particles will depend on the life cycle, structure of the body integument, and behavioral patterns of the different species. In the present study, we evaluated the potential of three synanthropic species of blowflies (genus Chrysomya: Calliphoridae) as bioindicators of potentially toxic metals at sites in the Brazilian Cerrado savanna, including both anthropogenic and preserved areas. Overall, we found that the mean concentrations of heavy metals were higher in soils of the preserved environments, but that only lead and zinc were significantly different; lead was higher in preserved areas, while zinc was higher in impacted ones. We also found no discernible variation in heavy metal assimilation factors between the adult males and females of any of the blowfly species. However, we did find species-specific differences in the capacity of the different calliphorids to detect contamination, although more detailed studies will be necessary to identify the biological factors that determine the capacity of these species to assimilate heavy metals.