Methods for the diagnosis of acute 3-chloro-p-toluidine hydrochloride poisoning in birds and the estimation of secondary hazards to wildlife

Female boat-tailed grackles poisoned with 3-chloro-p-toluidine hydrochlorid e (CPTH) were analyzed by necropsy and gas chromatography-mass spectrometry (GC-MS). The necropsies identified the presence of a white precipitate in the pericardium, which had been previously reported as a characteristic of CPTH-exposed birds. The CC-MS method, which utilized deuterated CPTH as a s urrogate, quantified CPTH residues in the breast tissue and gastrointestina l tract of CPTH-exposed birds. Comparison of these techniques indicated tha t the GC-MS method was more accurate for assessing CPTH poisoning in birds. Regression analyses of consumption versus residue data indicated that the sum of breast and gastrointestinal residues can be used as an estimator of CPTH exposure. Comparison of CPTH residues in grackles with toxicity data f or a variety of scavenger and predator species provided risk quotients of l ess than 0.1. Analysis of these data suggests that secondary hazards associ ated with the use of CPTH as an avicide for the control of pest birds are m inimal.