Two-generation reproduction study of hydrotreated shale oil vapors

Abstract

Two generations of Sprague-Dawley rats were each exposed to vapors generated by countercurrent distillation (50°C) at 0, 0.5, 2.5, and 5.0 mg/liter, for 6 hr/day, 5 days/week, for 124–126 days prior to mating. After mating, exposure was continuous except for the last day of gestation through lactation for F 0 dams, and the last day of gestation through Day 6 of lactation for F 1 dams. F 1 pups were not exposed during lactation; F 2 pups were excosed via nursing only. Body weights were recorded weekly before mating; organ and body weights were recorded on Days 1, 13, and 30 of gestation and on Days 1, 4, and 21 of lactation. Histopathology, reproductive performance, and certain sperm parameters were evaluated. The test material significantly ( p < 0.05) depressed body weights of F 0 males and brain and lung weights of F 1 weanling males at 5.0 mg/liter. Testicular weights of F 1 weanling males were depressed at the 0.5 and 5.0 mg/liter concentrations. While a dose-related decrease in sperm count and sperm ATP levels and an increase in ATP/sperm ratios were observed in F 0 males at 2.5 and 5.0 mg/liter, there was no adverse effect on overall reproductive performance.