EPA Science Inventory

Potential Scenarios for Nanomaterial Release and Subsequent Alteration in the Environment

Citation:

NOWACK, B., J. F. RANVILLE, S. A. DIAMOND, J. A. GALLEGO-URREA, C. METCALFE, J. ROSE, N. HORNE, A. A. KOELMANS, AND S. J. KLAINE. Potential Scenarios for Nanomaterial Release and Subsequent Alteration in the Environment. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, 31(1):50-59, (2012).

Description:

The risk associated with engineered nanomaterials (ENMs) will be determined in part by the processes that control their environmental fate and transformation. These processes act not only on ENMs that might be released directly to the environment, but perhaps more importantly also act on ENM in products and those that have been released from the product. The environmental fate and transformation is likely to differ significantly for each of these cases. The ENM released from actual direct use or from nano-containing products are much more relevant for ecotoxicological studies and risk assessment than pristine ENMs, The released ENMs may have a greater or lesser environmental impact than the starting materials, depending on the transformation reactions and the material. Almost nothing is known about the environmental behavior and the effects of released and transformed ENM, although these are the materials that are actually present in the environment. Further research also needs to show if the release and transformation processes result in a similar or more diverse set of ENM, and ultimately how this affects environmental behavior. These questions are addressed in this article using four brief case studies that cover a wide range of ENMs, their direct use or product application, and their likely fate in the environment. Furthermore, a more definitive classification scheme for ENM should be adopted that reflects their surface condition, which is a result of both industrial and environmental process acting on the ENM. We conclude that it is not possible to assess the risk of use of ENM by investigating only the naked (pristine) form of the ENM without considering alteration and transformation processes.

Purpose/Objective:

The risk associated with engineered nanomaterials (ENMs) will be determined in part by the processes that control their environmental fate and transformation. These processes act not only on ENMs that might be released directly to the environment, but perhaps more importantly also act on ENM in products and those that have been released from the product. The environmental fate and transformation is likely to differ significantly for each of these cases. The ENM released from actual direct use or from nano-containing products are much more relevant for ecotoxicological studies and risk assessment than pristine ENMs, The released ENMs may have a greater or lesser environmental impact than the starting materials, depending on the transformation reactions and the material. Almost nothing is known about the environmental behavior and the effects of released and transformed ENM, although these are the materials that are actually present in the environment. Further research also needs to show if the release and transformation processes result in a similar or more diverse set of ENM, and ultimately how this affects environmental behavior. These questions are addressed in this article using four brief case studies that cover a wide range of ENMs, their direct use or product application, and their likely fate in the environment. Furthermore, a more definitive classification scheme for ENM should be adopted that reflects their surface condition, which is a result of both industrial and environmental process acting on the ENM. We conclude that it is not possible to assess the risk of use of ENM by investigating only the naked (pristine) form of the ENM without considering alteration and transformation processes.

Record Details:

Record Type: DOCUMENT (JOURNAL/PEER REVIEWED JOURNAL)
Start Date: 01/01/2012
Completion Date: 01/01/2012
Record Last Revised: 10/10/2012
Record Created: 11/03/2011
Record Released: 11/03/2011
OMB Category: Other
Record ID: 239272

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL HEALTH AND ENVIRONMENTAL EFFECTS RESEARCH LAB

MID-CONTINENT ECOLOGY DIVISION

ECOLOGICAL TOXICOLOGY RESEARCH BRANCH