The Role of Chirocephalus diaphanus in the Early Recognition of Environmental Pollution by Trace Elements

A study was undertaken to evaluate whether the fairy shrimp Chirocephalus diaphanus (Crustacea: Anostraca) could be considered as a species capable of biomonitoring environmental contamination by accumulating trace elements. This preliminary investigation aimed at assessing the levels of As, Cd, Cu, Hg, Pb, Se, and Zn in natural waters as well as in adults and cysts of fairy shrimps sampled from five different sites in central Italy. Trace elements were determined by inductively coupled plasma (ICP)-based spectrometry. In particular, ICP-mass spectrometry (ICP-MS) was resorted to in most cases due to its high detection power. Pretreatment of samples (adults and cysts) consisted basically in the HNO3-assisted microwave digestion of the material. The highest levels of trace elements were found in the anostracan cysts, with concentration ranges (μg/g) of 0.464-3.11 for As, up to 0.820 for Cd, 2.62-13.0 for Cu, 0.011-0.213 for Hg, 0.966-8.46 for Pb, 0.295-2.45 for Se, and 16.4-50.4 for Zn. On the other hand, the lowest concentrations were found in natural waters, with values close to the ICP-MS detection power for some elements. These data are probative of a bioconcentration process, the extent of which is proportional to the environmental level of each element. This may turn out to be useful in planning biological monitoring and assessing ecotoxicological consequences which might ensue from the diffusion of the exploitation of such organisms in aquaculture.