Sentinel species and environmental contaminants: evidence from Metals, Rare Earth Elements and PFAS biomonitoring

Environmental contamination represents an increasing concern for wildlife, ecosystem integrity, and public health within a One Health perspective1,2,3. The aim of these studies was to evaluate the exposure to environmental contaminants in wild terrestrial mammals through the use of sentinel species and both invasive and non-invasive biological matrices. In the first study, liver and kidney samples from 30 crested porcupines (Hystrix cristata) collected in Central Italy between January 2020 and July 2025 were analysed to investigate the accumulation of potentially toxic metals and rare earth elements (REEs). Elemental concentrations were determined using quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS). Data distribution was assessed using the Shapiro-Wilk test, whereas tissue and sex-related differences were evaluated using Mann-Whitney U and Kruskal-Wallis non-parametric tests. In the second study, hair samples from 58 wild terrestrial mammals with different feeding behaviours, classified as herbivores, omnivores, and predators, were analysed for poly- and perfluoroalkyl substances (PFASs) using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Data normality was assessed using the Shapiro-Wilk test, and differences among feeding behaviour groups were analysed using Kruskal-Wallis test. In H. cristata, cadmium and selenium showed significantly higher concentrations in kidney tissue, whereas iron, zinc, and several REEs were more abundant in the liver. Sex-related differences were also observed for manganese and some hepatic REEs. In wildlife hair samples, PFASs were detected in all investigated species, with PFNA and PFOA showing the highest concentrations in predators than in herbivores, suggesting the influence of trophic level and biomagnification processes. Overall, these findings highlight the value of wild terrestrial mammals as sentinel species and demonstrate that integrating invasive and noninvasive matrices can strengthen environmental biomonitoring strategies and improve surveillance of terrestrial contamination within a One Health framework.