Determination of chlorophacinone in prairie dogs by microwave extraction and ion-pairing reversed-phase high performance liquid chromatography with confirmation by HPLC/MS

AGRO 11

Thomas M. Primus, thomas.m.primus@aphis.usda.gov, Chad R. Wermager, chad.r.wermager@aphis.usda.gov, and John J. Johnston, john.j.johnston@aphis.usda.gov. USDA/APHIS/WS/National Wildlife Research Center, 4101 LaPorte Ave., Ft. Collins, CO 80521
Chlorophacinone is an anticoagulant used to control ground squirrels, pocket gophers, and mountain beavers. Chlorophacinone is currently being assessed for control of prairie dogs. To assess potential secondary hazards to scavengers, residues of chlorophacinone in the carcasses must be determined and a risk assessment completed. Residues in liver and whole body tissue samples are typically determined by ion-pairing reversed-phase HPLC after microwave extraction of the sample combined with a solid phase extraction clean-up procedure. All samples were determined with the addition of diphacinone as a surrogate. Chlorophacinone and metabolites were detected. The metabolites were confirmed by HPLC/MS with atmospheric pressure chemical ionization and an ion trap detector after replacing the ion-pairing system with a HPLC/MS compatible mobile phase. Extracts were analyzed in full scan mode and with MS/MS to confirm the presence of chlorophacinone and to identify the metabolites of chlorophacinone. Hydroxy metabolites were observed and identified.
 

Agrochemical Residue & Metabolism Chemistry
8:55 AM-11:20 AM, Sunday, August 19, 2007 BCEC -- 259B, Oral

Division of Agrochemicals

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007