TOXICITY OF CARBON NANOTUBES: SPECIFIC AND DISTANT EFFECTS, EXPOSURE SCENARIOS, RISK ASSESSMENT (REVIEW OF LITERATURE)

Abstract

The article contains the survey and analysis of data on specific and long-term effects of the toxic action of carbon nanotubes (CNT) (organotoxicity, genotoxicity, reproductive toxicity, embryotoxicity, immunotoxicity, allergenicity, carcinogenic action), evaluation of exposure risks and assessment in different receipt ways, including inhalation and intake with a variety of products. Search and selection of sources for the review was carried out with the use of public databases, including PubMed, Scopus, Google Scholar, and RISC, for the period from 2004 to 2016. In total 109 publications were analyzed for the purposes of the review. Currently, harmful effects of CNT concerning the genetic apparatus of cells is proved on the highest level of evidence and appears to be mediated by oxidative cellular stress responses, signaling cascades activation, expression of cytokines and other regulatory factors. According to the International Agency for Research on Cancer (IARC) CNTs should be attributed to a group of carcinogenic substances 2B (“possibly carcinogenic to humans”). In assessing the risks of CNTs it is important to take into account their ability to enhance allergic sensitization, influence the toxicity of a number of environmental contaminants. Safe level (MCL) for multiwalled CNTs in the air of working area is 1 mg/m3, and taking into account data accumulation on the long-term effects of CNT, there are prospects for further reduction of the mentioned normative level.