Abstract |
Male and female Sprague-Dawley rats were exposed to target vapor concentrations of 0.100, 0.035, 0.003, or 0 mg/L (34, 12, 1, or 0ppm) of the test substance 6 hours per day, 5 days per week (excluding one holiday) for 21 exposures. Five animals per sex per group were terminated the day after the last exposure. An additional five animals per sex from the 0.100 and 0 mg/L groups were allowed to recover for 14 days following the exposure period. All animals survived to scheduled sacrifice. Animals were observed for clinical signs of toxicity each morning, once per hour during each exposure, and immediately after termination of each exposure. No test substance-related clinical abnormalities were observed. Body weights and feed consumption were measured weekly. Mean body weight, body weight gains, feed consumption, and fee utilization were comparable among the groups throughout the study. On Day 30 the main study animals were anesthetized with Isoflurane and blood were obtained from the posterior vena cava for clinical chemistry analyses. Fasted body weights and selected organ weights were measured at necropsy. Selected tissues were collected from all animals. On Day 44, the recovery animals were anesthetized, bled, and necropsied in the same manner as the main study animals. The mean urea nitrogen level was higher (p less than or equal to 0.05) for the main study 0.100 mg/L female group when compared with the control group. All other clinical chemistry parameters for the main study and recovery animals were comparable among the groups. Mean terminal body weights and absolute and relative (to body weight) organ weights for the main study and recovery animals were comparable among the groups. |