Assessment of the exposure to heavy metals in Griffon vultures (Gyps fulvus) from the Iberian Peninsula

Abstract Griffon vultures ( Gyps fulvus ), by virtue of their position at the top of the food chain and as obligate scavengers, are at risk of accumulating and concentrating heavy metals in their tissues and may be more predisposed to their toxic effects. The aim of this study is to investigate heavy metal concentrations in Griffon vultures in Portugal and Catalonia, Spain and to determine if heavy metal concentrations in the blood of weak and/or injured Griffon vultures admitted to wildlife rehabilitation centres (WRC) reflect contamination profiles in the local, free-living and outwardly healthy population. Whole-blood samples taken from 121 Griffon vultures caught in the wild or admitted to WRC in Portugal and Catalonia, Spain were examined for cadmium (Cd), mercury (Hg) and lead (Pb) by inductively coupled plasma mass spectrometry (ICP-MS). Cd and Hg were not detected in most samples (98.3% and 95%, respectively), while Pb was detected in all birds in concentrations ranging between 4.97 and 300.23 µg/dl. Birds admitted to WRC had significantly lower Pb concentrations (24.15±15.07 and 25.98±18.04 µg/dl in Portugal and Catalonia, Spain, respectively) than animals caught in the wild (29.67±13.19 and 42.22±50.08 µg/dl in Portugal and Catalonia, Spain, respectively) ( p