Genotoxic effects of chromium oxide nanoparticles and microparticles in Wistar rats after 28 days of repeated oral exposure.
The nanotechnology industry has advanced rapidly in the last 10 years giving rise to the growth of the nanoparticles (NPs) with great potential in various arenas. However, the same properties that make NPs interesting raise concerns because their toxicity has not been explored. The in vivo toxicology of chromium oxide (Cr2O3)-NPs is not known till date. Therefore, this study investigated the 28-day repeated toxicity after 30, 300 and 1000 mg/kg body weight (bw)/day oral treatment with Cr2O3-NPs and Cr2O3 microparticles (MPs) in Wistar rats. The mean size of Cr2O3-NPs and Cr2O3-MPs was 34.89 ± 2.65 nm and 3.76 ± 3.41 μm, respectively. Genotoxicity was assessed using comet, micronucleus and chromosomal aberration (CA) assays. The results revealed a significant increase in DNA damage in peripheral blood leucocytes and liver, micronuclei and CA in bone marrow after exposure of 300 and 1000 mg/kg doses of Cr2O3-NPs and Cr2O3-MPs only at 1000 mg/kg bw/day. Cr biodistribution was observed in all the tissues in a dose-dependent manner. The maximum amount of Cr was found in the kidneys and least in the brain of the treated rats. More of the Cr was excreted in the faeces than in the urine. Furthermore, nanotreated rats displayed much higher absorption and tissue accumulation. These findings provide initial data of the probable genotoxicity and biodistribution of NPs and MPs of Cr2O3 generated through repeated oral treatment.
Toxicology Unit, Biology Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500 007, India.
Shailendra Pratap
SP
Singh
Toxicology Unit, Biology Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500 007, India.|Department of Genetics, Osmania University, Osmania University Main Road, Hyderabad, Telangana, 500007, India.
Srinivas
S
Chinde
Defence Metallurgical Research Laboratory, Kanchanbagh, Hyderabad, Telangana, 500058, India.
Sarika Srinivas Kalyan
SS
Kamal
Toxicology Unit, Biology Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500 007, India.
M F
MF
Rahman
Toxicology Unit, Biology Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500 007, India.
M
M
Mahboob
Toxicology Unit, Biology Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500 007, India. paramgrover@gmail.com.
Paramjit
P
Grover
D000284:Administration, Oral; D000818:Animals; D017608:Chromium Compounds / Q000633:toxicity*; D002869:Chromosome Aberrations; D004249:DNA Damage; D005260:Female; D008099:Liver / Q000187:drug effects; D008297:Male; D015162:Micronucleus Tests; D009153:Mutagens / Q000633:toxicity*; D053758:Nanoparticles / Q000633:toxicity*; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution
D017608:Chromium Compounds; D009153:Mutagens; C023600:chromic oxide
Biodistribution; Characterization; Chromium oxide nanoparticles; Chromosomal aberrations; Comet; Micronucleus test