Monitoring essential and non-essential elements in lemurs using non-invasive sampling: a one health perspective

Monitoring essential and non-essential elements of endangered animal species represents a rising challenge in animal health conservation. This study employed a non-invasive biomonitoring approach to evaluate the elemental composition in fur, feces, and blood of four lemur species (Lemur catta, Eulemur macaco, Eulemur mongoz, Eulemur rubriventer) collected in two different zoological parks: Bioparco Zoom (Cumiana,Turin, Italy) and Parc Botanique et Zoologique de Tsimbazaza (PBZT, Antananarivo, Madagascar). Elemental analysis was performed via Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), and Graphite Furnace Atomic Absorption Spectroscopy (GF-AAS) following standardized mineralization protocols. Results highlight significant differences in element content among biological matrices, geographical origin, and seasons. The fur dataset is related to the long-term accumulation mechanism, reflecting the geochemical properties of the original habitat, while the feces dataset exhibits a sensitivity to environmental short-term changes as seasonal ones. The experimental results were processed with multivariate chemometric techniques. Pb, Al, Ba, and Fe were identified as the elements that describe Malagasy samples in alliance with the anthropogenic polluted origin area. Italian fur samples were characterized by As, Cr, Cu, and Ni, reflecting the element content of the soil in the area around Turin. Seasonal separation patterns observed in both fur and feces datasets suggest climatic influences on bioavailability and exposure pathways. This study demonstrates the efficiency of non-invasive biomonitoring as a practical and ethical method for assessing ecosystem and animal health in conservational contests. The proposed approach is in line with the One Health principles, offering a replicable model for future applications in both natural and managed environments, contributing to the development of targeted strategies for the protection of biodiversity.