The prenatal developmental toxicity of bitumen fume was tested by nose-only inhalation in the rat. The fumes for exposure were collected from the headspace of a storage tank filled with a bitumen corresponding in composition to an anticipated worst-case occupational exposure. The composition of these fumes was compared to actual paving site fumes to ensure its representativeness for workplace exposures. In a dose-range-finding study male and female rats were exposed to 0, 103, 480 or 1043 mg/m³ of fume (as total organic mass), for 6 h/day during 20 days post conception (p.c.). Dose-related effects on body weight and lungs were observed in the mid- and high-dose groups. In the main study, dams were exposed to 0, 52, 151 and 482 mg/m³ of fume, for 6 h/day during 19 days p.c. The maternal NOAEL was 52 mg/m³. In the high-dose group treatment-related effects on body weight (gain), food consumption, lung weights, and histopathological changes in lungs and larynx were observed. In the mid-dose group only histopathological changes in the larynx and lungs were found. The NOAEL for prenatal developmental toxicity was 151 mg/m³ based on reduced fetal weight in the high-dose group (482 mg/m³). However, these changes are most likely a consequence of the maternal toxicity, in particular the reduction of maternal body weight gain by 26 % as compared to control. Nose-only exposure to bitumen fumes in concentrations up to 482 mg/m³ from days 1–19 p.c. did not induce any significant fetal anomalies.

通过仅用鼻子吸入大鼠来测试沥青烟雾的产前发育毒性。用于暴露的烟雾是从装有沥青的储罐的顶部空间收集的，沥青的成分与预期的最坏情况职业暴露相对应。将这些烟雾的成分与实际的铺路场地烟雾进行比较，以确保其对工作场所暴露的代表性。在一项剂量范围探索研究中，雄性和雌性大鼠在受孕后 20 天内每天暴露于 0、103、480 或 1043 mg/m ³的烟雾（以总有机质量计）6 小时 (pc)。在中剂量组和高剂量组中观察到对体重和肺部的剂量相关影响。在主要研究中，母鼠在 19 天内每天暴露于 0、52、151 和 482 mg/m ³烟雾中 6 小时，母体 NOAEL 为 52 mg/m3。在高剂量组中，观察到治疗相关的对体重（增加）、食物消耗、肺重量以及肺和喉组织病理学变化的影响。在中等剂量组中，仅发现喉部和肺部的组织病理学变化。基于高剂量组胎儿体重降低（482 mg/m3），产前发育毒性的 NOAEL 为 151 mg/m3。然而，这些变化很可能是母体毒性的结果，特别是与对照相比，母体体重增加减少了 26%。从第 1-19 天仅用鼻子接触浓度高达 482 mg/m3 的沥青烟雾，不会引起任何明显的胎儿异常。