Safety Assessment of a Hemp Extract using Genotoxicity and Oral Repeat-Dose Toxicity Studies in Sprague-Dawley Rats

Dziwenka, Margitta; Coppock, Robert; Alexander, McCorkle; Palumbo, Eddie; Ramirez, Carlos; Lermer, Stephen

A full necropsy was done on each study animal including animals removed from the studies. Included in the necropsy were examination of the external body surface, body orifices, and the thoracic, abdominal and cranial cavities inclusive of contents. All surviving animals were weighed, anesthetized with isoflurane and exsanguinated from the abdominal aorta. All gross lesions were recorded. Absolute and normalized organ weights (organ weight/body weight) were determined on selected tissues ( Table 5 ). The eyes, epididymides, optic nerve and testes were fixed in modified Davidson's fixative and then stored in ethanol. All other tissues were fixed in 10% neutral buffered formalin. Specified tissues were embedded in wax, thin sections cut and stained with hematoxylin and eosin, and examined by light microscopy for histopathology (Table 5 ). For the 14-day study, liver and adrenal glands from all treatment and control animals, and the kidneys from Groups 1 and 4 were examined by histopathology. For the 90-day study, tissues from all animals removed from the study, tissues from Groups 1 and 4 and the livers from Groups 2 and 3 and groups 5 to 8 were examined for histopathologic changes by light microscopy ( Table 5 ). All gross lesions observed were described, the tissues taken and examined by histopathology. All pathology procedures were under the supervision of a veterinary pathologist 5 .