High Levels of Heavy Metals detected in Feathers of an Avian Scavenger Warn of a High Pollution Risk in the Atacama Desert (Chile)

The Atacama Desert represents the highest levels of mining exploitation in Chile, which inexorably results in high levels of pollution. Raptors, and particularly scavengers, have shown their usefulness to evaluate exposure to environmental contaminants in polluted scenarios. In this study, we used primary feathers from a local avian scavenger, turkey vulture Cathartes aura, to evaluate the exposure to cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) in two locations from the southern Atacama Desert (coastal and inland) and a third location from the bordering semiarid region, in northern Chile. All metals were detected in all analyzed samples (n = 54). Mean concentrations in Coastal Atacama were 0.68 +/- 0.84 ppm for Cd; 1.97 +/- 2.01 ppm for Pb; 59.11 +/- 80.69 ppm for Cu; and 107.96 +/- 51.00 ppm for Zn, while mean concentrations in Inland Atacama were 0.55 +/- 0.42 ppm for Cd; 3.37 +/- 2.61 ppm for Pb; 91.66 +/- 77.74 ppm for Cu; and 214.03 +/- 99.08 ppm for Zn. Mean concentrations in Coastal Coquimbo were 0.63 +/- 0.69 ppm for Cd; 1.57 +/- 0.92 ppm for Pb; 18.09 +/- 6.12 ppm for Cu; and 149.37 +/- 105.56 ppm for Zn. These differences could be explained by differences on abundance of mining settlements among areas. According to the literature, these values are very high for all metals, exceeding in some cases those values referred as responsible of health disorders in birds. We strongly recommend further research looking at potential adverse effects caused by heavy metal pollution on the health of human and wildlife populations in the southern Atacama Desert.

Automated summary

The Atacama Desert in Chile, known for its high levels of mining exploitation, has resulted in significant pollution levels. A study using primary feathers from turkey vultures found varying concentrations of cadmium, lead, copper, and zinc in different regions, with differences potentially attributed to the abundance of mining settlements. High metal concentrations were detected, exceeding levels known to cause health issues in birds, highlighting the need for further research on the impacts of heavy metal pollution on human and wildlife populations in the region.