TOXICITY OF CARBON NANOTUBES - Carbon Nanotubes: From Bench Chemistry to Promising Biomedical Applications - page 218

Chapter 8
TOXICITY OF CARBON NANOTUBES
Tapas Ranjan Nayak and Giorgia Pastorin
Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore
[e-mail]
8.1 INTRODUCTION
Until very recently, the development of nanotechnology was mainly
constrained to electronics and engineering devices, representing an apparently
inoffensive phenomenon, but lately it has envisaged its potential application
into medicine and biology as well. Therefore, two major concerns have
emerged, one focused on the effects of these materials on the environment,
and the other one more vigilant on their role in the improvement of health
conditions. Due to the novelty of the topic, current available information
concerning the relative environmental and health risks of manufactured
nanoparticles or nanomaterials is severely absent and defective. For
example, the irst generation of nanomedicines (liposomal preparations)
were approved much before a real awareness existed about safety of
nanomaterials.
Amid all the materials reported under the common umbrella of
nanotechnology, carbon nanotubes (CNTs) have attracted the attention of
numerous scientists, due to the possibility of being applied in engineering,
physics, chemistry, materials science and biology. CNTs, both in single-
(SWCNTs) and multi-walled (MWCNTs) forms, are classiied as “synthetic
graphite” by the National Occupational Safety and Health Administration,
on the basis of the same honeycomb pattern ( http://www.osha.gov/dts/
chemicalsampling/data/CH_244000.html). H owever, such deinition might
not be exhaustive for the exposure to CNTs, since they present physicochemical