Quantum dots mediated embryotoxicity via placental damage.

The increasing use of nanoparticles in consumer products raises the concerns of their safety. This study investigated the biological effects of quantum dots (QD) exposure to rats during pregnancy. CdTe QD were injected on the 13th gestation day. Morphological features of 121 fetuses and histological analysis of placentas were performed on the 20th gestation day. The results showed that QD exhibit dose dependent embryotoxicity: survival rates of fetuses were 97% (5mg/kg dose), 86% (10mg/kg dose) and 43% (20mg/kg dose). QD exposure also resulted in the reduction of fetal body length and mass, disturbed ossification of limbs and caused placental tissue damage. QD exhibit no teratogenic effects at the applied doses. It is hypothesized that embryogenesis was impeded due to the placental damage rather than QD penetration and accumulation in the fetuses. To conclude, mothers should be protected from QD exposure during pregnancy.