Nanotechnology: Emerging Research and Implications for Health and Policy
Hence, it is not surprising that engineered nanomaterials (ENMs), consumer products incorporating ENMs, and nanotechnologies taking advantage of ENMs in industrial materials and processes have attracted a remarkable amount of attention during the past decade. The unique technological and beneficial properties of ENMs are attributable to their small size, a large surface-to-volume ratio, reactivity, often excellent electrical conductivity, persistency, and high tensile strength [2, 3]. Several of the novel applications of ENMs have now been incorporated into a variety of popular consumer products, for example, better protection against ultraviolet (UV) radiation by sunblock creams containing nanoscale titanium dioxide (TiO2) nanomaterials as effective UV filters. ENMs are also now widely used in other consumer items such as cosmetics, clothes, cleaning materials such as bleach, sportswear, and other sport products such as cross-country skis or tennis rackets . Industrial applications include computer hard drives with much higher memory capabilities, as well as incorporation of these materials into semiconductors. The unique properties of ENMs may confer remarkable economic benefits by increasing the capacity of various types of information and communication technology (ICT) devices. They also may achieve it possible to make savings by reducing material needs, for example, increasing the strength of concrete in the construction industry means that the amount of concrete and other building materials needed can be significantly cut back. Nonetheless, the economically most important applications of ENMs are likely to be found in industrial applications such as coatings, optical and printed electronics, applications of nanocellulose, and energy production. ENMs are being also used as oil (nanodiamonds) and gasoline (cerium oxide) additives where they reduce friction (diamonds) or decrease the release of carbon dioxide (cerium oxide improving the burning of gasoline) (see ). On the other hand, it has been noted that these materials do not only possess beneficial properties, but in some cases they can also be harmful to human health or the environment. In fact, many of the characteristic properties of ENMs, small size (at least one dimension between 1 and 100 nm), a large surface area per weight, and reactivity, which make them technologically so valuable, are unfortunately the very reasons for their potentially harmful effects [5, 6]. Figure 17.1 depicts the expected size of the market of products
incorporating ENMs by 2020 , and Fig. 17.2 illustrates the number of consumer products whose labels indicate that they contain ENMs .