Evaluation of the teratogenic potential and reproductive toxicity of coal-derived naphtha

Liquids which are derived from coal liquefaction processes and boil above approximately 250 degrees C have induced terata in rats. However, few studies have addressed the teratogenic potential of coal liquids which boil below 250 degrees C. The present studies evaluated the reproductive and teratogenic potential of EDS hydrotreated naphtha, a refined coal liquid boiling below 177 degrees C. These studies were conducted by inhalation exposures with Sprague-Dawley rats at target vapor concentrations of 0.2, 1.0, and 5.0 g/m3. The first study assessed teratogenesis. There was no evidence that inhalation exposures for 6 hr per day between Days 6 and 19 of gestation induced maternal toxicity, fetal toxicity, or malformation. In a second study, rats were exposed for 6 hr per day, 5 days per week for 13 weeks, and then mated to assess reproductive toxicity. There was little evidence that inhalation exposure to EDS hydrotreated naphtha adversely affected reproductive performance or fetal development in Sprague-Dawley rats. A low incidence of malformations was observed in treated groups, but these malformations were probably not treatment related.