The ICP-OES method for determination of zinc in Enchytraeus crypticus and agarose gel from ecotoxicological tests

A simple ICP-OES (inductively coupled plasma optical emission spectrometry) method for determination of zinc in Enchytraeus crypticus and agarose gel samples from ecotoxicological tests is proposed. The E. crypticus individuals are separated, water washed, wet weighed and dissolved in tetramethylammonium hydroxide. The gel is digested in HNO3. The method (limit of detection in mg kg−1: 0.90 for E. crypticus bulk biomass, 14 for one E. crypticus worm and 0.0018 for gel) was employed in the evaluation of ZnO nanoparticles (ZnO-NPs) compared to ZnCl2: bioaccumulation factors were 57–180 for ZnCl2 and 23–65 for ZnO-NPs.