Evaluation of bioconcentration of trace elements in the Western Mediterranean mouse (Mus spretus Lataste, 1883) at two Moroccan wetland sites

Abstract Many micromammals were shown to be vulnerable to metallic trace elements and are therefore suitable for biomonitoring. The objective of our research is to assess the exposure of a small rodent, Mus spretus, as a bioindicator of pollution to trace elements. We have determined the concentrations of Cu, Pb, Cr, Zn and Fe in the liver, kidneys and heart of 71 individuals of Mus spretus in north-west Morocco in two areas: Merja Zerga and Dayet Erroumi. Tissue metal concentrations in this species varied widely with age, sex, sites and organs. The concentration of Cu in the liver was the highest among all the metals and was recorded in adult females of Merja Zerga with a maximum of 60 µg / g ; at Dayet Erroumi, it was around 14 µg / g. At the same time, we found a similar trend for Fe, Pb, Cr and Zn in the three organs in males and females at the two sites. Highly significant differences between females at the two sites were recorded for the variables weight (W) and head to body length (TL) (t = -3.992; p < 0.001 and t = -2.242, p < 0.05), however, males obtained equal values ​​in the two sites. Spatiotemporal monitoring in small mammals must be studied, but requires the application of a non-lethal estimator.