Report on SOP for dispersing nanomaterials in water and report on round robin test

This report describes a standard operation procedure for dispersion of nanomaterialsin liquids prior to toxicological or ecotoxicological testing. Mainfactors, who determine the state of agglomeration and aggregation ofENMs after dispersion are specific energy input, particle concentrationand fluid composition. The method was validated in two round robin tests,where two typical nanomaterials (a nanopowder and a nanodispersion)were investigated. One main result arising out of the data comparison wasthat only those participants, who were able to follow the instructions in theSOPs completely, received similar results regarding particle size and zetapotential. The SOP is easy to adapt for other types of nanomaterials. Theresults provide the standardization process and were presented at DINworking group.