Grantee Research Project Results
2006 Progress Report: Impacts of Manufactured Nanomaterials on Human Health and the Environment - A Focus on Nanoparticulate Aerosol and Atmospherically Processed Nanoparticulate Aerosol
EPA Grant Number: R831717Title: Impacts of Manufactured Nanomaterials on Human Health and the Environment - A Focus on Nanoparticulate Aerosol and Atmospherically Processed Nanoparticulate Aerosol
Investigators: Grassian, Vicki H. , Thorne, Peter S. , O'Shaughnessy, Patrick
Institution: University of Iowa
EPA Project Officer: Aja, Hayley
Project Period: October 1, 2004 through September 30, 2007
Project Period Covered by this Report: October 1, 2005 through September 30, 2006
Project Amount: $335,000
RFA: Exploratory Research to Anticipate Future Environmental Issues: Impacts of Manufactured Nanomaterials on Human Health and the Environment (2003) RFA Text | Recipients Lists
Research Category: Nanotechnology , Human Health , Safer Chemicals
Objective:
In this research, the potential effects of manufactured nanoparticle aerosol on human health are being investigated. This research is being conducted to satisfy three main objectives. These objectives are to: (1) fully characterize a variety of manufactured nanomaterials in terms of their size, shape, bulk, and surface properties; (2) determine if engineered nanomaterials are particularly deleterious to health compared to particles from combustion processes that have been more extensively studied; and (3) evaluate the relative health effects caused by different surface coatings on the nanoparticle.
Manufactured nanomaterials are purchased from several sources and further characterized using a wide variety of techniques and analysis methods, including surface spectroscopy so that both bulk and surface properties can be understood on a molecular level. These well-characterized particles then are used for inhalation and exposure studies. There also is additional characterization once the aerosol has been generated to determine if the particles aggregate or retain the size distribution determined prior to aerosol generation. Toxicology assessments include murine assays to screen for acute and sub-chronic pulmonary effects.
Progress Summary:
In the past year, the potential effects of manufactured nanoparticles on human health have been investigated. In particular, our studies have focused on some of the smallest commercially available nanoparticles, ca. 5 nm TiO2. These particles are pure anatase and their surfaces are truncated by surface hydroxyl groups and adsorbed water under ambient conditions. Thus, there are no surface coatings present from manufacturing. The particles form an aerosol with an aggregate size of approximately 120 nm. It has been determined that sub-chronic inhalation exposure to TiO2 nanoparticles caused an increase in the number of activated macrophages in mice; however, mice recovered after 3 weeks post exposure. There were no signs of pathological changes in the bronchoalveolar lavage fluid or in lung tissue found in this study. An acute inhalation and instillation study did not show the expected “surface area effect” for 5 versus 20 nm nanoparticles. Aggregation state (aggregate size and porosity) may be the more important factor in inflammatory response.
Studies on other nanomaterials and the impacts of surface coatings are underway. We find that 25 nm Fe nanoparticles are similar to 5 nm TiO2 nanoparticles, showing moderate inflammatory responses. However, new data show 25 nm Cu nanoparticles produce the largest inflammatory response observed thus far.
Future Activities:
Future activities will focus on determining the toxicity of other manufactured nanoparticles including carbon nanotubes. The impact of surface coatings on nanoparticle toxicity also will be explored.
Journal Articles on this Report : 1 Displayed | Download in RIS Format
| Other project views: | All 21 publications | 6 publications in selected types | All 5 journal articles |
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Grassian VH, O'Shaughnessy PT, Adamcakova-Dodd A, Pettibone JM, Thorne PS. Inhalation exposure study of titanium dioxide nanoparticles with a primary particle size of 2 to 5 nm. Environmental Health Perspectives 2007;115(3):397-402. |
R831717 (2005) R831717 (2006) R831717 (2007) |
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Supplemental Keywords:
ambient air, risk assessment, health effects, human health, particulates, environmental chemistry, industry,, Health, Scientific Discipline, PHYSICAL ASPECTS, Health Risk Assessment, Physical Processes, Risk Assessments, Environmental Chemistry, Biochemistry, cytokines, particle size, human exposure, particulate matter, engineered nanomaterials, ambient particle health effects, exposure, nanotechnology, respiratory impact, inhalation toxicology, human health risk, inhalation study, particle exposure, biochemical researchRelevant Websites:
http://research.uiowa.edu/nniui Exit
http://www.chem.uiowa.edu/faculty/grassian/index.html Exit
http://www.public-health.uiowa.edu/academics/faculty/patrick_oshaughnessy.html Exit
http://www.public-health.uiowa.edu/academics/faculty/peter_thorne.html Exit
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.