Determination of the metal uptake in single organisms - Corophium volutator - via complementary ETV/ICP-MS and LA/ICP-MS.

RATIONALE (Eco-)toxicological effects are mostly derived empirically and is not correlated with a metal uptake. Furthermore, if the metal content is determined mostly bulk analysis of the whole organism population is conducted; thus, biological variability is completely disregarded and this may lead to misleading results. To overcome this issue, we compared two different solid sampling techniques for the analysis of single organisms. METHODS In this study, complementary ETV/ ⇔LA/ICP-MS based methods for the analysis of individual organisms were developed and compared with the concentrations obtained after digestion and measured by ICP-MS. For this purpose, a common (eco-)toxicological test organism, the mud shrimp Corophium volutator, was selected. As proof-of-concept application these organisms were incubated with environmentally relevant metals from galvanic anodes, which are often used for metal corrosion protection in e.g. offshore wind farms. RESULTS With the bulk analysis conducted we could show that an enrichment of the incubated elements was detectable. With the ETV/ICP-MS method it was possible to identify a high biovariability within the population of organisms tested. Using the LA/ICP-MS method, it could be determined that the enrichment of the elements detectable was due to adsorption of the metals and not to uptake, which correlates well with the absence of (eco-)toxicological effects. CONCLUSIONS The results obtained imply the efficiency of complementary methods to explain the absence or presence of (eco-)toxicological effects. Especially methods that allow for single organism analysis or provide even a spatial resolution support the interpretation of ecotoxicological findings.