Aspect ratio has no effect on genotoxicity of multi-wall carbon nanotubes

作者：Kim Jin Sik; Lee Kyu; Lee Young Hee; Cho Hyun Sun; Kim Ki Heon; Choi Kyung Hee; Lee Sang Hee; Song Kyung Seuk; Kang Chang Soo; Yu Il Je^*

来源：Archives of Toxicology, 2011, 85(7): 775-786.

DOI：10.1007/s00204-010-0574-0

• Carbon nanotubes (CNTs)
• Multi-wall carbon nanotubes (MWCNTs)
• Genotoxicity
• OECD test guidelines
• Bacterial reverse mutation test
• In vitro chromosome aberration test
• In vivo micronuclei test
• Good laboratory practice (GLP)
• Cytotoxicity

Carbon nanotubes (CNTs) have specific physico-chemical and electrical properties that are useful for telecommunications, medicine, materials, manufacturing processes and the environmental and energy sectors. Yet, despite their many advantages, it is also important to determine whether CNTs may represent a hazard to the environment and human health. Like asbestos, the aspect ratio (length:diameter) and metal components of CNTs are known to have an effect on the toxicity of carbon nanotubes. Thus, to evaluate the toxic potential of CNTs in relation to their aspect ratio and metal contamination, in vivo and in vitro genotoxicity tests were conducted using high-aspect-ratio (diameter: 10-15 nm, length: similar to 10 mu m) and low-aspect-ratio multi-wall carbon nanotubes (MWCNTs, diameter: 10-15 nm, length: similar to 150 nm) according to OECD test guidelines 471 (bacterial reverse mutation test), 473 (in vitro chromosome aberration test), and 474 (in vivo micronuclei test) with a good laboratory practice system. To determine the treatment concentration for all the tests, a solubility and dispersive test was performed, and a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) solution found to be more suitable than distilled water. Neither the high- nor the low-aspect-ratio MWCNTs induced any genotoxicity in a bacterial reverse mutation test (similar to 1,000 mu g/plate), in vitro chromosome aberration test (without S9: similar to 6.25 mu g/ml, with S9: similar to 50 mu g/ml), or in vivo micronuclei test (similar to 50 mg/kg). However, the high-aspect-ratio MWCNTs were found to be more toxic than the low-aspect-ratio MWCNTs. Thus, while high-aspect-ratio MWCNTs do not induce direct genotoxicity or metabolic activation-mediated genotoxicity, genotoxicity could still be induced indirectly through oxidative stress or inflammation.

• 出版日期2011-7