The recent availability of a cryostream cooler at beamline L has allowed synchrotron radiation based micro-XRF analysis of frozen biological samples close to their native state. In a previous contribution, we compared the elemental distributions within a ydrated (frozen) and a fixed (dehydrated) Daphnia magna, which is a freshwater crustacean used in toxicological research as a model organism for evaluating effects of metals on the cosystem. Although hydrated samples show less dislocation of elements and/or sample contamination as compared to fixed samples, they are mainly composed of a water matrix, which is more susceptible to absorption effects of low energy X-rays. Therefore, we investigate the degree of absorption in 2D/CT micro-XRF elemental maps of Daphnia magna using a dual silicon drift detector (SDD) setup
