Assessment of Antimycin a Use in Fisheries and its Potential for Reregistration

Fisheries managers and catfish farmers have used the piscicide antimycin A (antimycin) as a management tool for about 35 years. In 1993, the United States Environmental Protection Agency (EPA), under the authority of the Federal Insecticide, Fungicide, and Rodenticide Act, required the reregistration of antimycin and the completion of expensive environmental fate and residue studies. To justify the expense, we investigated the potential of antimycin as a piscicide in North America and its potential for reregistration in the United States by (a) surveying government agencies and private catfish farmers, (b) analyzing the literature, and (c) determining the feasibility of completing the studies required for reregistration. Sales data indicate that agencies use about 5 kg of antimycin annually (one‐quarter of sales), and catfish farmers use the remainder. Catfish farmers use antimycin to remove scaled fish from production ponds, and agencies now use the limited amount of antimycin in western and midwestern states mainly for restoration of threatened, endangered, or native trout species in streams. Completion of the environmental fate and residue studies was considered problematic due to technical and financial issues. Foremost was the concern that methods to adequately detect and quantify antimycin and its metabolites at the levels required for testing were not available. In response to these difficulties and limited and restricted use, EPA (a) reduced the number of environmental fate studies, (b) eliminated the requirement to quantify degradates, and (c) may not require a residue study. The United States Fish and Wildlife Service will likely have to sponsor a limited and restricted use label and a standard operating procedures manual to continue using antimycin.