Of the main routes of exposure to environmental contaminants (dermal contact, ingestion, inhalation), inhalation is of the most concern to human health because we cannot control what we breathe as well as what we touch or eat. In fact, we are still discovering ways in which the inhalation of air pollutants (especially aerosols) affects health. We now know that air pollution kills 7 million people per year. Beyond that, we are curious about chronic, low-dose exposure levels that may be linked to conditions that we are still discovering. For example, exposure to PM2.5 (particulate matter < 2.5 micrometers) has been recently tied to mental health issues, such as brain aging and anxiety.
We are interested in using engineering concepts to characterize emissions of aerosols (small particle or droplets suspended in air) from everyday sources. These measurements can aid in developing tools and strategies to control emissions and minimize exposures, especially to vulnerable populations—such as children and the elderly, and incidentally exposed populations (i.e., bystanders of a certain activity). Applications of our research range from consumer safety and "safer by design" consumer products, to indoor and outdoor air pollution, soiling of photovoltaic panels and sustainability, air pollutant sensing, human health, and climate change.
Our mission is to perform research that will lead to a positive impact in human health and the environment.
Main research topics:
- Formation, transport, and fate of aerosols, ranging from ultrafine (<100 nm), fine (< 2.5 um), to coarse (2.5 - 10 um).
- Assessing and minimizing people's exposure to environmental contaminants
- Ambient and source aerosol sampling and characterization
- Understanding the release of nanomaterials or aerosols from consumer products
- Developing nanotechnology applications for environmental sustainability
Current and past projects:
- HOMEChem: A collaborative indoor air chemistry field study (2017 - present)
- IndoorChem: A community of researchers in the chemistry of indoor environments (2017 - present)
- Investigating the impacts of air pollution and weathering on the efficiency of photovoltaic systems (2017 - present)
- Emissions of ultrafine aerosols from 3D printers (2015 - present)
- NanoEarth: The Virginia Tech National Center for Earth and Environmental Nanotechnology Infrastructure (project ongoing, my participation ended in 2016)
- Characterization of nanoscale components of dust and aerosols in the city of Shanghai, China (2014 - 2016)
- Keeping track of nanotechnology in the real world: Redeveloping the Wilson Center’s Nanotechnology Consumer Products Inventory (2013 - 2015)
- Children's exposure to silver nanoparticles in nanotechnology-enabled consumer products (2010 - 2012)
- Consumer exposure to silver nanoparticles in spray products (2008 - 2012)
- Cal-Mex: Atmospheric Studies in the US-Mexico Border Region (2010)
- Indoor air quality in a Brazilian hospital (2007 - 2008)
- Development of methods for sampling and characterizing odorous air samples (2003 - 2008)
- Olfactometry and impact assessment of odors and VOCs in the vicinity of industrial sites (2003 - 2008)
- TSI scanning mobility particle sizer (SMPS) systems, including a 1-nm SMPS, nano DMA, and long DMA.
- TSI Nanoscan portable SMPS system + optical particle sizer for size distributions 12 - 10,000 nm
- Aethlabs 5-wavelength aethalometers
- Thermodenuder, atomizer
- 1 cubic meter teflon chamber
- Access to GC-MS, ICP-MS, transmission and scanning electron microscopy