Biomonitoring of heavy metals and metalloids with wild mammals in the Iberian Peninsula: a systematic review

Trace elements (including heavy metals) can negatively affect the environment and the health of living beings. Biomonitoring is a transdisciplinary tool to evaluate this pollution type and its respective consequences in ecosystems, food chains and webs. This review uses systematic methods to identify published literature on biomonitoring of heavy metal(loid)s using wild mammals on the Iberian Peninsula. A total of 30 different mammalian species (30/141) were included in 62 Iberian biomonitoring studies; 22 species from terrestrial habitats and 8 from aquatic habitats. Carnivores (including piscivores) are the most represented in both habitat types (7/22 in terrestrial; 8/8 in aquatic). Most studies used more than one tissue (2.8±1.3), with a preference for the liver and kidney. Cd was the most determined metal, measured in 45% of the biomonitoring studies analysed, highlighting its potential health impact on mammals. Further research is crucial to provide more information on mammalian species' susceptibility to this One Health problem; and to cover more habitats, trophic chains, and/or geographical areas.