Uptake and Effects of Carbon Nanotubes - Safety of Nanomaterials along Their Lifecycle - page 211

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Uptake and Effects of
Carbon Nanotubes

James C. Bonner

CONTENTS
10.1 Introduction .................................................................................................. 213
10.2 Lung Deposition and Translocation of Nanotubes ....................................... 214
10.3 Acute Responses ........................................................................................... 216
10.3.1 Macrophage-Mediated Uptake and Clearance ................................. 216
10.3.2 Cellular Responses to Nanotubes ..................................................... 217
10.4 Pathological Effects ...................................................................................... 219
10.4.1 Fibrosis and Granuloma Formation .................................................. 219
10.4.2 Pleural Disease and Cancer .............................................................. 221
10.4.3 Effects of CNTs beyond Lungs ......................................................... 224
10.4.4 Susceptibility Factors ........................................................................ 224
10.5 Conclusions and Summary ........................................................................... 225
References .............................................................................................................. 226

10.1 INTRODUCTION
Nanotechnology is a rapidly developing industry that promises great societal and
economic benefits. In particular, carbon nanotubes (CNTs) have enormous potential
for innovation in the fields of engineering, electronics, and medicine. However, recent
reviews of the scientific literature predict that CNTs will be a risk for lung diseases,
particularly pulmonary fibrosis and granuloma formation, related to occupational
and perhaps consumer exposure (Bonner 2010a, Bonner 2011). Inhalation studies
using mice or rats demonstrate that CNTs deposit reach the alveolar regions in the
lung and also migrate to the subpleural tissues beneath the mesothelial lining of
the lung, where they remain embedded in the extracellular matrix or within resident
lung cells for months following exposure (Ryman-Rasmussen et al. 2009a). CNTs
also localize in lymphoid tissues (Ma-Hock et al. 2009, Pauluhn 2010) and stimulate
systemic immune effects that influence extra-pulmonary tissues and organs such as
the spleen and heart (Mitchell et al. 2007, 2009). In addition, genetic and environ-
mental factors influence susceptibility to CNT-induced lung diseases in rodents. For
example, CNTs exacerbate allergen-induced airway inflammation in mice (Ryman-
Rasmussen et al. 2009b). The aim of this chapter is to summarize the uptake, fate,
and effects of CNTs following pulmonary exposure to rodents to predict possible

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