ERBIUM AFFECTS THE XENOPUS LAEVIS DEVELOPMENT

The use of lanthanides, also known as rare earth elements (REEs), in technological devices and their presence in the e-waste made them a new category of potential emerging contaminants (Gravina et al., 2018; Pagano et al., 2019). Their toxicological and ecotoxicological effects are still largely unknown. Erbium is one of the most widespread REEs with potential environmental and human health risks associated to its increased release (Tornero and Hanke, 2017). Reported lanthanides concentrations in the surface water usually vary from 10 ng/L to 200 ng/L (Neal, 2007); however, in the very polluted rivers lanthanides concentrations may increase up to 10 μg/L (Neal et al., 2005). Only few studies investigated the potential effects of REEs on a long-term basis in freshwater (Blaise et al., 2018; Blinova et al., 2018). The aim of our study is to examine the influence of Erbium on Xenopus laevis embryos, organism never experimented with this lanthanide, to test the eventual adverse effects on developing organisms. We used environmental (1 and 10 μg/L) and twice higher (20μg/L) concentrations. Our preliminary data indicate that Erbium induces alteration of morphology, with cephalic and abdominal edema and anomalous intestinal winding, ROS production and decreased heart rate, thus suggesting that erbium could be dangerous for X. laevis and other non-target species.