Development of a high performance liquid chromatography/mass spectroscopy method for the determination of strychnine concentrations in insects used to assess potential risks to insectivores

Authors

Randal S. Stahl, USDA-APHIS-Wildlife ServicesFollow
Wendy M. Arjo, US Department of Agriculture, APHIS/WS, National Wildlife Research Center
Kim K. Wagner, US Department of Agriculture, APHIS/WS, National Wildlife Research Center
Carol Furcolow, US Department of Agriculture, APHIS/WS, National Wildlife Research Center
Dale L. Nolte, USDA-APHIS-Wildlife ServicesFollow
John J. Johnston, US Department of Agriculture, APHIS/WS, National Wildlife Research CenterFollow

Document Type

Article

Date of this Version

October 2004

Comments

Published in Journal of Chromatography B, 811 (2004) 257–262.

Abstract

A high performance liquid chromatography/mass spectrometry (HPLC/MS) method was developed in support of a study to assess potential tertiary risks posed to insectivores by strychnine baited pocket gophers (Thomomys sp.). Necropholous insects are primary consumers of pocket gopher carcasses. A field study was conducted to collect insects from strychnine-baited and control pocket gopher carcasses. The majority of the insects collected were from the orders Diptera (flies, assayed separately as adults and larvae), Coleoptera (beetles), and Hymenoptera (ants and wasps, assayed separately). Samples (0.5 g) were extracted in acetic acid (2%) and analyzed with the mass spectrometer configured for tandem mass spectrometry. For most of the samples the strychnine concentrations were less than the method limit of detection. However, strychnine concentrations as high as 0.338, 0.341, 0.698, and 0.034 μg/g were detected in ants, fly adults, fly larvae, and beetles, respectively. This information collected with the HPLC/MS method is critical for assessing potential non-target hazards for insectivores.