Lessons Learned from Unintentional Aerosols - Safety of Nanomaterials along Their Lifecycle - page 97

5

Lessons Learned
from Unintentional
Aerosols

Joseph Brain

CONTENTS
5.1 Introduction .................................................................................................... 99
5.2 Types of Nanoparticles ................................................................................. 101
5.3 Characterizing Unintentional Aerosols ........................................................ 102
5.3.1 Size-Selective Samplers .................................................................... 102
5.3.2 Selecting Unintentional Aerosols from Polydisperse Particles ........ 102
5.4 Classes of Unintentional Aerosols ................................................................ 103
5.4.1 Tobacco Smoke ................................................................................. 103
5.4.2 Air Pollution ..................................................................................... 104
5.4.3 Occupational Exposures ................................................................... 106
5.4.4 Coal Dust .......................................................................................... 106
5.4.5 Non-Anthropogenic Sources ............................................................ 107
5.5 Biologic and Environmental Responses ....................................................... 107
5.6 Conclusion .................................................................................................... 108
References .............................................................................................................. 109

5.1 INTRODUCTION
Much of this topic focuses on nanomaterials as a new, and to some extent, unknown
class of materials. Physicists, chemists, and material scientists working with entre-
preneurs are designing engineered nanoparticles with novel characteristics and
properties appropriate to their application including paints, coatings, structural con-
stituents, to nanomedicines. This chapter emphasizes the reality that although many
nanomaterials are novel—such as fullerenes, graphene, carbon nanotubes, and nano-
medicines—others are familiar and have existed for millennia. In general, these
particles, which we will call unintentional particles, are the smallest particles in
a distribution of polydisperse particles produced through combustion or as a con-
sequence of evaporation and condensation of volatized materials such as metals,
organic compounds, or even sea water.
A key theme of this chapter is that polydisperse aerosols, particularly those from
combustion or crushing, have always included a nanofraction that can be detected

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