Abstract
In vivo micronucleus and Pig-a (phosphatidylinositol glycan, class A gene) mutation assays were conducted to evaluate the genotoxicity of 10nm titanium dioxide anatase nanoparticles (TiO2-NPs) in mice. Groups of five 6–7-week-old male B6C3F1 mice were treated intravenously for three consecutive days with 0.5, 5.0, and 50mg/kg TiO2-NPs for the two assays; mouse blood was sampled one day before the treatment and on Day 4, and Weeks 1, 2, 4, and 6 after the beginning of the treatment; Pig-a mutant frequencies were determined at Day −1 and Weeks 1, 2, 4 and 6, while percent micronucleated-reticulocyte (%MN-RET) frequencies were measured on Day 4 only. Additional animals were treated intravenously with three daily doses of 50mg/kg TiO2-NPs for the measurement of titanium levels in bone marrow after 4, 24, and 48h of the last treatment. The measurement indicated that the accumulation of the nanoparticles reached the peak in the tissue 4h after the administration and the levels were maintained for a few days. No increase in either Pig-a mutant frequency or the frequency of %MN-RETs was detected, although the %RETs was reduced in the treated animals on Day 4 in a dose-dependent manner indicating cytotoxicity of TiO2-NPs in the bone marrow. These results suggest that although TiO2-NPs can reach the mouse bone marrow and are capable of inducing cytotoxicity, the nanoparticles are not genotoxic when assessed with in vivo micronucleus and Pig-a gene mutation tests.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call