GFAAS and ICP-MS Determination of Ag and Cu in the Haemolymph of a Millimetric Marine Crustacean (Parhyale hawaiensis) as a Tool in Ecotoxicology

The determination of metals in aquatic organisms has become an important tool in ecotoxicological studies. In the present study, silver and copper were determined for the first time in the haemolymph of Parhyale bawaiettsis, a millimetric marine crustacean. Silver (Ag) was selected because this metal has become of environmental concern due its intense use in nanomaterials. Copper (Cu) was included in this study as a possible biological internal standard. The procedures for haemolymph collection, quantification, and preparation were optimized. The adult organisms were exposed to silver in concentrations from 0 to 100 mu g L-1 in a saline water medium for 96 hours. For quantification and comparison of the method, GFAAS and ICP-MS analysis was used and all operational conditions were optimized. It was found that the Ag concentrations in the haemolymph increased in relation to the increase in Ag concentration in the water, reaching 11 ng mg(-1). However, a plateau was observed at the two highest concentrations. More studies are required to verify the usefulness of copper as an internal standard. Both GFAAS and ICP-MS provided satisfactory results in the quantification of Ag and Cu in the haemolymph of these small animals and are an excellent tool for ecotoxicological studies, especially for the evaluation of silver from nanomaterials in the aquatic environment. (AU)