Suicidal poisoning by endothall

A fatal case of suicidal ingestion of the herbicide endothall (7-oxabicyclo [2,2,1]heptane-2,3-dicarboxylic acid) is described. Endothall was determined after initial phosphotungstic acid deproteination followed by extraction using 1,2-dichloroethane:tert-butanol (2:1) and subsequent injection into the gas chromatograph equipped with a flame ionization detector. Identity was confirmed by thin-layer chromatography, infrared spectrophotometry, and gas chromatography/mass spectrometry.