Page:Current Strategies for Engineering Controls in Nanomaterial Production and Downstream Handling Processes.pdf/17

 engineered nanomaterials being produced and used [Sellers et al. 2009]. Nano-sized silica, silver, and natural clays are also common materials in use. The carbon nanotube is a unique nanomaterial being investigated for a wide range of applications. These tubes are cylinders constructed of rolled-up graphene sheets. Another interesting carbon structure is a fullerene (also known as a Bucky Ball). These are spherical particles usually constructed from 60 carbon atoms arranged as 20 hexagons and 12 pentagons. As shown in Figure 1, the structure resembles a geodesic dome (designed by architect Buckminster Fuller, hence the name). Nanomaterials are widely used across industries and products, and they may be present in many forms.

Significant international health and safety research and guidance concerning the handling of nanomaterials is underway to support risk management of commercial developments. Both risks and rewards are inherent in these new materials. Scientists around the world are conducting toxicological studies on these nanomaterials, and initial findings are concerning. Animals exposed to titanium dioxide (TiO2) and carbon nanotubes (CNTs) have displayed pulmonary inflammation [Chou et al. 2008; Rossi et al. 2010; Shvedova et al. 2005]. Other studies have shown that nanoparticles can translocate to the circulatory system and to the brain and cause oxidative stress [Elder et al. 2006; Wang et al. 2008]. Perhaps the most troubling finding is that CNTs can cause asbestos-like pathology in mice [Poland et al. 2008; Takagi et al. 2008].

Figure 1. Atomic structure of a spherical fullerene

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