Toxicogenomics of Multi‐Walled Carbon Nanotubes: Fid-Bau Portal

Toxicogenomics of Multi‐Walled Carbon Nanotubes

Joseph, Pius

Advanced materials having at least one dimension in the nanoscale (1–100 nm) and manufactured for specific purposes are considered as engineered nanomaterials (ENMs). ENMs exhibit many unique properties, intended for superior performance compared with conventional materials, such as nano size, light weight, and increase in surface area, tensile strength, rigidity, and stability. Additionally, ENMs may exhibit superior electromagnetic, catalytic, thermal, and pharmacokinetic properties, facilitating their use in many commercial, industrial, and medical applications. Many of the same desirable properties of ENMs that enable their use in such applications have also raised concern from a human health and safety standpoint. For example, due to their light weight, ENMs can be easily aerosolized with potential for inhalation exposure among workers who are engaged in the manufacture of ENMs or ENM‐containing products. Similarly, the size of the ENMs in the nanoscale may enable their entry into deep anatomical areas in the lungs and interaction with cellular components to result in biological activity that may be quantitatively and/or qualitatively distinct from their large‐sized counterparts of similar chemical composition. Despite the limited epidemiological data, results obtained from many animal studies have demonstrated lung toxicity caused by exposure to ENMs. Many such studies were conducted using multi‐walled carbon nanotubes (MWCNT) whose potential to result in damage, inflammation, oxidative stress, fibrosis, genotoxicity, mesothelioma, and cancer in the lungs has been demonstrated. Toxicogenomic, in particular transcriptomic, studies conducted recently have identified the genes whose expressions were altered in response to pulmonary exposure to MWCNT. Bioinformatic analysis of the transcriptomic data has provided significant insight into the molecular mechanisms underlying the pulmonary toxicity of MWCNT. Our current understanding regarding the pulmonary toxicity of MWCNT and the molecular mechanisms underlying the toxicity are presented in this chapter.