Final Report: Implications of Nanomaterials Manufacture and Use: Development of a Methodology for Screening SustainabilityEPA Grant Number: R830910
Title: Implications of Nanomaterials Manufacture and Use: Development of a Methodology for Screening Sustainability
Investigators: Beaver, Earl R. , Beloff, Beth , Tanzil, Dicksen , Wiesner, Mark R.
Institution: BRIDGES to Sustainability , Rice University
EPA Project Officer: Lasat, Mitch
Project Period: May 1, 2003 through April 30, 2005
Project Amount: $99,740
RFA: Environmental Futures Research in Nanoscale Science Engineering and Technology (2002) RFA Text | Recipients Lists
Research Category: Nanotechnology , Safer Chemicals
The objective of this research project was to assess the potential costs and benefits of nanomaterials with near-term uses along their product lifecycles. This project constituted a step in developing a methodology to screen the sustainability of new technology applications in terms of environmental, societal, and economic risks and opportunities.
A literature review was conducted to summarize what is known about the sustainability impacts of nanomaterials, especially in terms of human health and the environment, and methodologies that have been developed to screen for sustainability and lifecycle impacts of new technology applications. There remains significant uncertainty regarding the fate of nanomaterials in the environment, exposure to humans and other organisms, and the effects of the exposure. Nevertheless, concerns regarding the impact of nanomaterials discussed in the literature may be broadly classified into four categories: (1) risks to human health; (2) risks to the environment; (3) risks to security; and (4) risks of public backlash.
There also are socioeconomic concerns such as the affordability (equity), ownership, and control of the technology. These concerns highlight the need to assess and communicate the potential risks and benefits of nanotechnology from a comprehensive, systemic framework.
Three representative uses of nanomaterials—titania nanoparticles in sunscreens,
alumoxane nanoparticles in ceramic membrane production, and fullerene/bucky
ball applications in near-term consumer products—were reviewed in terms
of their potential impacts and benefits along the lifecycle. These applications
exhibit different sets of potential risks and benefits along the lifecycle stages.
Although benefits are relatively clear, there are considerable uncertainties
with respect to negative impacts. The manufacture of the nanomaterials considered
here involves raw materials commonly used in the production of conventional
materials. Consequently, no major concerns were identified for the upstream
processes (i.e., raw material extraction, preparation, and transport). Benefits
of the near-term uses of the nanomaterials in improving the performance of consumer
products, increasing the efficiency of industrial processes, and enabling new
product innovations are relatively well understood. Considerable uncertainties,
however, are present regarding the risks of occupational exposure during production
and other manufacturing stages and the fate of the nanomaterials at end-of-life.
A relative risk assessment is presented for the industrial fabrication of several nanomaterials. Five nanomaterials were selected for this analysis based on their current or near-term potential for large-scale production and commercialization: single walled carbon nanotubes, bucky balls (C60), one variety of quantum dots, alumoxane nanoparticles, and nano-titanium dioxide. The assessment focused on the activities surrounding the fabrication of nanomaterials, exclusive of any impacts or risks with the nanomaterials themselves. A representative synthesis method was selected for each nanomaterial based on its potential for scale up. A list of input materials, output materials, and waste streams for each step of fabrication was developed and entered into a database that included key process characteristics such as temperature and pressure. The physical-chemical properties and quantities of the inventoried materials were used to assess relative risk based on factors such as volatility, carcinogenicity, flammability, toxicity, and persistence. These factors were combined using an actuarial protocol developed by the insurance industry for the purpose of calculating insurance premiums for chemical manufacturers. This protocol ranks three categories of risk relative to a 100 point scale (where 100 represents maximum risk): Incident Risk, Normal Operations Risk, and Latent Contamination Risk. Results from this analysis determined that relative environmental risk from manufacturing each of these five materials was comparatively low in relation to other common industrial manufacturing processes.
The actuarial risk assessment protocol also may be extended to other stages of the product lifecycle. This is especially straightforward when the nanomaterials are used in another manufacturing stage, such as in the production of ceramic membranes. Alumoxane nanoparticles reduce the time and energy required and eliminate the use of organic solvents in the fabrication of ceramic membranes. Thus, the use of alumoxane nanoparticles in the manufacture of ceramic membranes reduces the relative risk scores in all categories in comparison with the more conventional sol-gel technology.
This small grant project was limited by the lack of quantitative data on resource use, waste, and emissions in the manufacturing of nanomaterials, especially for industrial-scale processes (as opposed to bench-scale processes). In the absence of these data, more formal lifecycle assessment and lifecycle impact assessment could not be performed as originally intended. To overcome this challenge, a continuation of this project should include chemical process modeling and scale up, as well as greater involvement by researchers in the subject area who can provide the necessary bench-scale or industrial-scale data.
As a result of great uncertainty regarding the fate and impacts of nanomaterials in the workplace and the environment, risks associated with exposure to the nanomaterials were not included in the risk assessment of the manufacturing stage. Current work in investigating toxicology and environmental fate and transport of these near-term nanomaterials at Rice University and other institutions will go a long way toward filling this knowledge gap.
Journal Articles on this Report : 1 Displayed | Download in RIS Format
|Other project views:||All 3 publications||1 publications in selected types||All 1 journal articles|
||Robichaud CO, Tanzil D, Weilenmann U, Wiesner MR. Relative risk analysis of several manufactured nanomaterials: An insurance industry context. Environmental Science & Technology 2005;39(22):8985-8994.||