Medicine and Health Sciences Commons^™

Assessment Of Exposure To Composite Nanomaterials And Development Of A Personal Respiratory Deposition Sampler For Nanoparticles, Lorenzo Cena

Lorenzo Cena

The overall goals of this doctoral dissertation are to provide knowledge of workers' exposure to nanomaterials and to assist in the development of standard methods to measure personal exposure to nanomaterials in workplace environments.

To achieve the first goal, a field study investigated airborne particles generated from the weighing of bulk carbon nanotubes (CNTs) and the manual sanding of epoxy test samples reinforced with CNTs. This study also evaluated the effectiveness of three local exhaust ventilation (LEV) conditions (no LEV, custom fume hood and biosafety cabinet) for control of exposure to particles generated during sanding of CNT-epoxy nanocomposites. Particle number …

Particles In Welding Fumes, Rebecca T. Williams

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to investigate whether or not differing base metals and filler wires used during welding processes contributed to differing amounts of ultrafine particles (UFP) and nanoparticles being emitted during the welding procedure. The study was also conducted to determine UFP and nanoparticle exposure in the breathing zones of the welders as well as the breathing zones of pipefitters and fire watchers, who commonly sit 6ft behind the welding arc. In order to determine if UFP and NP exposures differed with base metal and filler wire, all welding processes utilized the same welding machine for metal …

Biokinetics Of Nanomaterials: The Role Of Biopersistence, Peter Laux, Christian Riebeling, Andy M. Booth, Joseph D. Brain, Josephine Brunner, Cristina Cerrillo, Otto Creutzenberg, Irina Estrela-Lopis, Thomas Gebel, Gunnar Johanson, Harald Jungnickel, Heiko Kock, Jutta Tentschert, Ahmed Tlili, Andreas Schäffer, Adriënne J. A. M. Sips, Robert A. Yokel, Andreas Luch

Pharmaceutical Sciences Faculty Publications

Nanotechnology risk management strategies and environmental regulations continue to rely on hazard and exposure assessment protocols developed for bulk materials, including larger size particles, while commercial application of nanomaterials (NMs) increases. In order to support and corroborate risk assessment of NMs for workers, consumers, and the environment it is crucial to establish the impact of biopersistence of NMs at realistic doses. In the future, such data will allow a more refined categorization of NMs. Despite many experiments on NM characterization and numerous in vitro and in vivo studies, several questions remain unanswered including the influence of biopersistence on the toxicity …

Generation And Characterization Of Nanoaerosols Using A Portable Scanning Mobility Particle Sizer And Electron Microscopy, Adam J. Marty

USF Tampa Graduate Theses and Dissertations

The purpose of this research is to demonstrate the ability to generate and characterize a nanometer sized aerosol using solutions, suspensions, and a bulk nanopowder, and to research the viability of using an acoustic dry aerosol generator/elutriator (ADAGE) to aerosolize a bulk nanopowder into a nanometer sized aerosol. The research compares the results from a portable scanning mobility particle sizer (SMPS) to the more traditional method of counting and sizing particles on a filter sample using scanning electron microscopy (SEM). Sodium chloride aerosol was used for the comparisons. The sputter coating thickness, a conductive coating necessary for SEM, was measured …

Exposure Assessment And Risk Management Of Engineered Nanoparticles : Investigation In Semiconductor Wafer Processing, Michele Shepard

Legacy Theses & Dissertations (2009 - 2024)

Engineered nanomaterials (ENMs) are currently used in hundreds of commercial products and industrial processes, with more applications being investigated. Nanomaterials have unique properties that differ from bulk materials. While these properties may enable technological advancements, the potential risks of ENMs to people and the environment are not yet fully understood. Certain low solubility nanoparticles are more toxic than their bulk material, such that existing occupational exposure limits may not be sufficiently protective for workers. Risk assessments are currently challenging due to gaps in data on the numerous emerging materials and applications as well as method uncertainties and limitations.