Airborne Nanoparticles: Generation, Characterization, and Occupational Exposure

Despite the rapid growth in nanotechnology, very little is known about the unintended health or environmental effects of manufactured nanomaterials. The development of nanotechnology risk assessments and regulations requires quantitative information on the potential for exposure to nanomaterials. In addition, to facilitate life-cycle assessments and inhalation toxicology studies, robust methods are needed to generate aerosolized engineered nanoparticles. We conducted a set of field studies to measure the fine particle mass concentrations (PM2.5) as well as nanoparticle number concentrations and size distributions in two nanomaterial manufacturing facilities. Measurements were performed near the reactor, in the breathing zone, and at a background site. Increases in PM2.5 and particle number concentrations were associated with physical handling of nanomaterials. The highest PM2.5 concentration observed was 2700 ug m-3 during sweeping of the reactor in the commercial plant. In most cases, an increase in the number of sub-100 nm particles accounted for the increase in total number concentrations. The results of this research can be used to develop guidelines for workplace regulations to minimize workers' exposure to nanoparticles. Furthermore, we used an atomizer to aerosolize C60 aggregates from a fullerene-water suspension. Measurement of particle size distributions and number concentrations showed that increasing the initial fullerene concentration resulted in increased number of aerosolized particles, while the average size of particles remained relatively constant. To return the aerosolized fullerenes into water, we passed the aerosol sample through an impinger. Reducing the flow rate through the impinger resulted in an increase in the collection efficiency of airborne nanoparticles.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Environmental Planning

Department dc:contributor.department

Environmental Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2007

Author dc:creator

• Yeganeh Talab, Behnoush

Chair dc:contributor.committeechair

• Marr, Linsey C.

Committee members dc:contributor.committeemember

• Vikesland, Peter J.
• Love, Nancy G.

• workplace exposure
• particle control
• nanoparticles
• nanomaterials
• C60 fullerene
• occupational health

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-03202007-124201

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/41734