Suspected glyphosate poisoning in a dog

Abstract

Glyphosate is a widely used pesticide that has been associated with poisoning in both humans and animals. Its toxicity remains a topic of controversy, particularly regarding its carcinogenic potential. This study aimed to investigate a suspected case of glyphosate poisoning in a dog, providing a detailed account of the case history, clinical evolution, laboratory findings, and genotoxic assessment. A seven-month-old dog was referred to the Veterinary Hospital, presenting with mental confusion and ataxia. The pet guardian reported altered consciousness and incoordination twelve days after Roundup® was applied to the farm’s grass. A complete blood count revealed normocytic normochromic anemia, a packed cell volume of 20%, thrombocytopenia (50,000/µL), and severe leukocytosis (447,200/µL), with 95% of the white blood cells consisting of blasts of unidentified origin and 5% segmented neutrophils. Myelogram analysis showed a moderately cellular bone marrow sample with a predominance of primitive cells of undetermined origin (>95%), suggesting a diagnosis of leukemia. To further investigate the potential link between leukemia and glyphosate exposure, whole blood was collected in a heparinized tube for a comet assay. The test indicated moderate DNA damage. Chemotherapy was recommended; however, treatment was not pursued for personal reasons, and the patient died five days after the consultation. A necropsy was not authorized. This report contributes to the understanding of glyphosate poisoning and its potential health consequences, particularly its association with hematologic malignancies in canines.