The neurotoxic substance beta, beta-iminodipropionitrile (IDPN), which induces hyperkinesia in some mammals, was found to be neurotoxic to the brine shrimp Artemia salina L. (Crustacea, Anostraca) inducing discoordination of limb-movement and sedation of motility. Up to 9 metabolities of IDPN were