Adverse effects of diisooctyl phthalate on the male rat reproductive development following prenatal exposure

Abstract

In a first study, rats were given diisooctyl phthalate (DIOP, CAS 27554-26-3) at 0, 0.1, 0.5, and 1g/kg/day, by gavage, on gestation days 6–20 (GD). There was a significant increase in resorptions at 1g/kg/day and a reduction in fetal weights at 0.5 and 1g/kg/day. Malpositioned testes were observed in fetuses at 1g/kg/day, and supernumerary lumbar ribs and ossification delay at 0.5 and 1g/kg/day. In a follow-up study, DIOP administered on GD 12–19 reduced fetal testicular testosterone at 0.1g/kg/day and above. Finally, postnatal reproductive assessment was conducted in adult male offspring prenatally exposed to DIOP on GD 12–21. Abnormalities of reproductive system (e.g. hypospadias, non scrotal testes, and hypospermatogenesis) were observed in a few adult males at 0.5g/kg/day, and with a high incidence at 1g/kg/day. Thus, DIOP displayed an antiandrogenic activity and disrupted the male reproductive development.