Histopathological Changes in the Hepatopancreas of Porcellio Laevis (Crustacea, Isopoda) After Exposure to Cd and Zn Mixture

The ultrastructural changes on the hepatopancreas of Porcellio laevis individuals were investigated after their exposure to a mixture of cadmium (Cd) and zinc (Zn) during four weeks. At the end of the experiment, trace element (TE) concentrations were determined using atomic absorption spectrometry (AAS). The growth of individuals was calculated and compared among the treatments. From the first week until the end of the experiment, a weight gain was observed in P. laevis individuals. Additionally, the TE concentrations in the hepatopancreas and in the rest of the body were considerable and seem to be dose dependent. Moreover, our results confirmed the role of the hepatopancreas as the main storage organ. Thus, the conducted transmission electron microscopy highlighted remarkable alterations on the hepatopancreas cells resulting from the Cd and Zn bioaccumulation. The displayed alterations are principally the disorganization of the S- and B-cells leading to a destruction of the microvilli border, an increase of the lipid droplets and mitochondria as well as the appearance of trace elements in the form of B-type granules. Based on the obtained results herein, we can conclude that Porcellio laevis might be a good candidate in the prevention of TE pollution in the terrestrial ecosystems.