In vivo Genotoxicity of Silver Nanoparticles after 90-day Silver Nanoparticle Inhalation Exposure

OBJECTIVES: The antimicrobial activity of silver nanoparticles has resulted in their widespread use in many consumer products. Yet, despite their many advantages, it is also important to determine whether silver nanoparticles may represent a hazard to the environment and human health. METHODS: Thus, to evaluate the genotoxic potential of silver nanoparticles, in vivo genotoxicity testing (OECD 474, in vivo micronuclei test) was conducted after exposing male and female Sprague-Dawley rats to silver nanoparticles by inhalation for 90 days according to OECD test guideline 413 (Subchronic Inhalation Toxicity: 90 Day Study) with a good laboratory practice system. The rats were exposed to silver nanoparticles (18 nm diameter) at concentrations of 0.7 x 10(6) particles/cm3 (low dose), 1.4 x 10(6) particles/cm3 (middle dose), and 2.9 x 10(6) particles/cm3 (high dose) for 6 hr/day in an inhalation chamber for 90 days. The rats were killed 24 hr after the last administration, then the femurs were removed and the bone marrow collected and evaluated for micronucleus induction. RESULTS: There were no statistically significant differences in the micronucleated polychromatic erythrocytes or in the ratio of polychromatic erythrocytes among the total erythrocytes after silver nanoparticle exposure when compared with the control. CONCLUSION: The present results suggest that exposure to silver nanoparticles by inhalation for 90 days does not induce genetic toxicity in male and female rat bone marrow in vivo.

Study on Mutagenesis of Leflunomide 3-methyl-isomer to Mice / 中国药房

0.05).CONCLUSION:The mutagenesis of Leflunomide 3-methyl-isomer was not observed in these tests.

A Study on Micronuclei and DNA Damage of Bone Marrow Cells of Mice Induced by Holmium Ions of Rare Earths / 环境与健康杂志

Objective To investigate the genotoxicity of heavy rare-earth holmium to bone-marrow cells of mice.Methods Kunming mice were randomly divided into six groups and were given holmium-trioxide-HCl by gavage at several doses of 0,10,20,40,80 and 160 mg/kg bw respectively one time a day for two days;other Kunming mice were randomly divided into 3 groups and holmium nitrate was given i.p.at doses of 10,40 and 80 mg/kg bw respectively one time a day for two days.24 hours after the last treatment,the bone-marrow cells of thighbone were collected for micronuclei analysis and single cell gel electrophoresis (SCGE).Results Frequencies of micronuclei were increased by the 2 kinds of holmium solutions at the dosage from 10 to 80 mg/kg bw with a dose-effect relationship,but at the dose of 160 mg/kg bw,it was lower than the negative control.In SCGE,the average tail length increased significantly (P

A Study on Genetic Toxicity of Formaldehyde / 环境与健康杂志

Objective To explore the genotoxicity of formaldehyde to mice.Methods Mice were exposed to formaldehyde of several concentrations(1.25,0.50,and 5.00 mg/m3) in the toxicant exposure chamber,2 h/d for 15 consecutive days.Bone marrow micronuclei test and single cell gel electrophoresis were employed to test the genotoxicity.Results Compared with the control group,a significant increase in the rate of micronuclei and the DNA damage of peripheral lymphocytes in experimental groups were found.As to the rate of micronuclei and DNA damage,an obvious dose-effect relationship was showed.Conclusion Formaldehyde has a genotoxic effect for mice,much more attention should be paid in this research field.