Nanomaterial Case Studies: Nanoscale Titanium Dioxide in Water Treatment and in Topical Sunscreen (Final)
Notice EPA is announcing the availability of this final report, Nanomaterial Case Studies: Nanoscale Titanium Dioxide in Water Treatment and in Topical Sunscreen. To learn more about the research done on nanomaterials, visit http://www.epa.gov/ncea/nano.
Nanoscale materials (nanomaterials) have been described as having at least one dimension on the order of approximately 1 to 100 nanometers (nm). Such materials often have unique or novel properties that arise from their small size. This document is a starting point to determine what is known and what needs to be known about selected nanomaterials as part of a process to identify and prioritize research to inform future assessments of the potential ecological and health implications of these materials. Two specific applications of nanoscale titanium dioxide (nano-TiO2) are considered: (1) as an agent for removing arsenic from drinking water; and (2) as an active ingredient in topical sunscreen. These “case studies” do not represent completed or even preliminary assessments, nor are they intended to serve as a basis for risk management decisions in the near term on these specific uses of nano-TiO2. Rather, the intent is to use this document in developing the scientific and technical information needed for future assessment efforts.
The case studies are organized around the comprehensive environmental assessment (CEA) framework, which includes a product life-cycle perspective with the risk assessment paradigm and encompasses fate and transport processes, exposure-dose characterization, and indirect as well as direct ecological and human health impacts. The intent of these case studies is to characterize the current state of knowledge on the environmental impacts of nano-TiO2 as used in these two specific applications, as well as areas where information is missing. Note that some information gaps are specific to nano-TiO2 either as a drinking water treatment agent or as an ingredient in topical sunscreen. Other gaps may pertain more broadly to nano-TiO2 irrespective of its application, and still other gaps may pertain even more widely to nanomaterials in general. In this way, the case studies are expected to be used in developing research strategies that will support comprehensive environmental assessments of nanomaterials.
|Feb 2007||EPA released the Nanotechnology White Paper which recommends the development of case studies to identify unique risk assessment considerations and research needed to support risk assessment efforts for nanomaterials.|
|Jul 2009||EPA released the Nanomaterial Case Studies: Nanoscale Titanium Dioxide (External Review Draft) for public review and comment.|
|Sep 2009||EPA held a workshop to identify and prioritize research questions related to nano-TiO2 ("Nanomaterial Case Studies Workshop: Developing a Comprehensive Environmental Assessment Research Strategy for Nanoscale Titanium Dioxide,” Research Triangle Park, NC, September 29-30, 2009). A summary report (PDF) is available that describes the workshop and summarizes the collective prioritization results.|
|Apr 2010||EPA conducted an independent external peer review of the draft case studies document.|
|Nov 2010||EPA released the final report.|
This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.
- (204 pp, 5 MB, about PDF)