Journal of Clinical Toxicology
Open Access
ISSN: 2161-0495
ISSN: 2161-0495
Cowan VE and Blakley BR
Objective: Wildlife death from organophosphate and carbamate pesticide exposure has been documented previously in Canada. Wildlife exposure to these agents can occur through primary toxicity (i.e., inhalation), ingestion of contaminated water or food, or secondary toxicity through scavenging on toxic carrion. This paper describes epidemiologic information pertaining to confirmed acetyl cholinesterase inhibitor pesticide lethality in the coyote and bald eagle over a 16-year period in the Canadian Prairies.
Methods: Epidemiologic case information from the diagnostic records of Prairie Diagnostic Services confirmed lethal acetyl cholinesterase inhibitor poisoning in 58 coyotes (Canis latrans) and 60 bald eagles (Haliaeetus leucocephalus) from 1998 to 2013. Brain acetyl cholinesterase enzyme activity suppressed to 50% or greater was indicative of toxicity and death.
Results: Coyote case submissions varied both annually (p<0.0001) and temporally (p<0.0001). Submissions were highest in the years of 2000, 200, and 2002 (collectively 46.6%). The months of most frequent submission were May and April (36.2%). Bald eagle cases were also influenced annually (p<0.0001) and temporally (p<0.0001). Confirmed poisoning in bald eagle carcasses was most frequent during two seasonal periods: May through April and December through January. Years 2000, 200, and 2004 comprised 43.3% of the bald eagle poisonings during the investigational period. Annual and temporal distribution of coyote and bald eagle cases were comparable but were not significantly correlated. Brain acetyl cholinesterase activities within 20% of the mean in unaffected cases were considered background. These activities were 3.44 ± 1.52 μmol/min/g in the coyote and 15.18 ± 3.37 μmol/g/min in the bald eagle.
Conclusion: Poisoning in wildlife with acetyl cholinesterase inhibitor pesticides continues to be a regular occurrence in the Canadian prairies. Increased surveillance and monitoring of pesticide use should be considered to mitigate future poisonings.