On March 19, 2021, the European Union (EU) Observatory for Nanomaterials (EUON) published a Nanopinion entitled “ECETOC task force ensures society benefits from safe nanomaterials via efficient safety assessments that require minimal animal testing” by authors from BASF and the Center for Chemical Safety Assessment (ECETOC).  The column reviews ways to assess the safety of nanomaterials while minimizing animal testing.  According to the authors, the NanoApp developed by the ECETOC Task Force on Nanomaterials helps users group similar nanoforms, which can be useful when registering nanoforms via sets of similar nanoforms, or when doing read-across between nanoforms for particular information requirements.