FIGURE 3-1 Central topics for EHS research on ENMs. Research on the EHS aspects of nanotechnology can be organized into groupings that map onto a framework that considers how a source of nanomaterial (left) may result in an organism or ecosystem response (right).
Although Figure 3-1 presents a paradigm for organizing information about nanotechnology and its risks, it does not address the full diversity of exposed populations. Occupational exposure to ENMs is likely, given the extensive research enterprise and burgeoning startup business community. Inhalation exposure in manufacturing may occur if processes rely on gas-phase production of materials or if materials are aerosolized. Consumer exposure to ENMs also is of immediate interest in that makers of products ranging from sunscreens to car bumpers have touted the inclusion of nanotechnology (PEN 2011). Topical and ingestion exposure from use of personal-care and other consumer products is possible. And the environment is exposed through disposal or intentional application of ENMs for remediation and through incidental or accidental release and runoff. However, those different exposure scenarios involve many common research issues, particularly in the early stages of the ENM life cycle. Because research on risks to human vs ecosystem health poses different challenges, particularly when ENM-related hazards are considered, the discussion in some sections is separated to reflect these differences.
The discussion below is organized according to the source-to-response paradigm to address critical gaps, but many key questions in nanotechnology-EHS research are intrinsically systems problems that can be addressed only by integrating the interactions of various components of the paradigm (See Figures 2-1 and 3-1). The assumptions and data from the more established foundation disciplines of pulmonary toxicology, environmental impact analysis, nanomedicine, and risk assessment are discussed where relevant. The chapter concludes with a compilation of research questions based around Figure 3-1 (see Table 3-1); the questions capture issues that are critical to the many stakeholders responsible for managing potential ENM-related risks.