Abstract |
Groups of 10 male and 10 female Sprague Dawley rats received methyl acetate by nose-only inhalation exposure at concentrations of 0, 75, 350 or 2000 ppm for a period of 28 days (6 hours per day, 5 days per week). One day after the last administration all animals were killed and necropsied. Concentrations of the test compound in the respiratory air were monitored several times daily via IR analysis. Additionally, chemical analyses were carried out at weekly intentals. Behavior and state of health were observed daily in all groups. Body weights and food consumption were recorded twice weekly. Hematological and clinical chemistry examinations were carried out at the termination of the study. Furthermore, urine analysis was performed at the termination of the study. Blood levels of the test compound were determined at different times after cessation of the last exposure in order to characterize elimination kinetics. During necropsy the animals were examined for macroscopically visible abnormalities, the main organs weighed and the organ to body weight ratios calculated. Many organs and tissues were processed for histopathological examination and checked for microscopically visible changes. |