Glenn C. Morrison Associate
Professor of Civil, Architectural and Environmental Engineering 221 (573) 341-7192;
MY ACADEMIC INTERESTS
I’m most interested in the physics and chemistry of indoor air pollution. You’ll see statistics on many web-sites stating that indoor air quality is much worse than outdoor air quality. This is broadly true, but needs to be qualified. Some (but not all) chemical and particulate pollutants do exist at higher concentrations indoors than outdoors because they are often generated indoors. In a 1997 analysis, an EPA risk assessment group placed several indoor pollutants among the top 5 environmental health risks to North Americans. Given the human health imperative, I attempt to promote awareness of the problem in the courses I teach and the research projects I and my students work on. Check out my acting skills (such as they are) in this Public Service Announcement produced by students at the University of Texas, Austin, IGERT program. For a comprehensive CV go here. Also, check out the activities of the Environmental Research Center.
COURSES I TEACH AT MS&T
Introduction to Environmental Engineering
Introduction to Air Pollution
Air Pollution Control
Physico-Chemical Processes in Environmental Engineering
Indoor Air Pollution
CURRENT RESEARCH AND RELATED PROJECTS
1) Chemistry and transport near and on human surfaces. Since proximity to a pollutant source is as
important at the source strength, we have begun evaluating pollutant dynamics
and chemistry in the region around the human body, specifically the head
region. We have learned that ozone flux to human hair is very fast, and that
ozone reactions with human sebum will be responsible for lower ozone exposure,
but also responsible for higher exposure to oxidation products such as
aldehydes and ketones. Relevant journal
article: Pandrangi
and Morrison, 2008. Also excerpted at New
Scientist, Discover and Popular
Science. Also see our collaborative work with NIOSH on squalene, a
component of skin oil: Wells et al., 2008.
Working with Atila Novoselac and
Donghyun Rim of the University of Texas, Austin, we have simulated ozone and
reaction product concentrations in the human breathing zone. This work
demonstrates that ozone is substantially depleted in the breathing zone and
that microenvironmental measurements overestimate ozone exposure. Relevant journal article: Rim, Novoselac and Morrison, 2009 (Early
view at Indoor Air, DOI: 10.1111/j.1600-0668.2009.00595.x)
Continuing to work with the fine
folks at the University of Texas, Austin, (specifically Richard Corsi) we have
also learned that ozone will react with fragrances (e.g. perfumes) around the
head region, increasing exposure to sub-micron aerosol that are produced by these reactions. Relevant journal article: Corsi et al., 2007. Check our Rich
Corsi’s head shot in National Geographic!
2) Building materials as passive filters
of indoor air pollution. Buildings may have the ability to remove indoor
air pollutants effectively and passively (no energy required!). The US Green Building
Council has awarded us a grant (2009-2010) to develop test methods that can
identify materials that are effective at reducing indoor concentrations of
ozone and ozone reaction products. This is a collaborative project with the UT
Austin. This research builds on conceptual development presented at Healthy Buildings, Lisbon, 2009 and a
more recent collaboration with the UT Austin. UT student Donna Kunkel shows
that some materials are very effective at passively removing ozone in the UT
test house. Ultimately these materials, if used to retrofit homes of at-risk
individuals, could improve longevity and quality of life for those living in
smoggy cities. Relevant conference papers
Morrison et al., 2006 and Kunkel et al. 2008.
3) Exposure history derived from indoor
surfaces. In one of my newer research projects, I am exploring the
possibility of extracting indoor exposure histories for air pollutants from the
building materials themselves. For example, the diffusion of benzene into vinyl
flooring leaves a quantifiable concentration profile. This profile is analogous
to a fuzzy photograph of the recent time-history of indoor benzene
concentrations. Thus, core samples of materials such as vinyl flooring,
concrete, paint, or even couch cushions can provide rich detail about the
timing and intensity of indoor pollution episodes. Relevant journal article: Morrison
et al., 2007.
More recently, undergraduate Jon McKinney has been tackling this problem with gusto and has developed methods to measure concentrations gradients within solid building furnishings. These measurements are the next piece of the puzzle in our goal of evaluating exposures in the past. Jon has won several research poster competitions, and won a competitive EPA GRO fellowship to support his research for the 2008-2009 school year. Go Jon!
4) Workshop
on Interfacial Chemistry in Indoor Environments. In July of 2007, we
put on a workshop sponsored by the National Science Foundation and the
California Air Resources Board. The objectives of this workshop were to
identify research needs and rank gaps in the existing knowledgebase of indoor
interfacial chemistry as it relates to human exposure to air pollutants. Based
on presentations and discussions, the participants identified the most fruitful
short-term research courses to follow, outlined medium and long-term research
goals, instigated new collaborations and identified key existing resources and
necessary improvements to the existing research infrastructure. Many recommendations
for future research were put forward in workshop discussions; the following
summarize research priorities with notable consensus:
1. A molecular level understanding of physical and chemical processes occurring at indoor surfaces
2. Composition and morphology of indoor surfaces and interfaces
3. Health consequences of indoor air/interfacial chemistry
4. Reactions occurring at the human interface and with human residues (e.g. skin oils) and bioeffluents
A complete report with seminar
topics, participants, and recommendations can be found here: WICIE 2007 workshop report (Featured in Environmental Science and
Technology).
SPECIAL THANKS TO Lucretia Eaton of the UMR Environmental Research Center!
5) Field
evaluation of secondary pollutant emissions in homes. My National Science Foundation CAREER award is
funding field research to determine the extent of ozone initiated surface
chemistry in real homes. Following several homes over a period of years, this
research will show whether the slow accumulation of surface oils and dirt is
more important than the underlying surfaces in controlling overall secondary
emissions into homes. This comprehensive five-year project includes
laboratory and field chamber experiments. Small laboratory chambers are used to
measure ozone induced aldehyde emission rates on representative materials from
real homes. Field chambers are used to periodically isolate and test indoor
surfaces in the homes themselves to examine the influence of surface aging,
soiling and cleaning. Relevant journal
article: Wang and Morrison, 2006
6) Indoor surface chemistry of terpenes.
Many consumer products and personal care products release huge amounts of
fragrance compounds known as terpenes and terpenoids. These compounds readily
react with ozone in air, but what about surfaces? It turns out that indoor
surfaces can hold onto fragrance molecules, thus providing them more time to
react with ozone (if they so choose!). We are in the early stages of
quantifying the fundamental reaction rates at surfaces with the goal of better
understanding how air fresheners and perfumes affect indoor air quality. Relevant conference paper: Springs and Morrison, 2007
7) Alkaline/acidic organic pollutant
interactions with indoor surfaces. Internal funding (
8) Pollutant transport to indoor surfaces. In conjunction with my surface chemistry work, I am pursuing a better understanding of the physics of pollutant transport to and from indoor surfaces. My students and I have developed several methods for measuring indoor mass-transfer coefficients and have been applying them to real indoor settings. Using micro flux-sensors, we are able to measure transport in real-time and correlate this with indoor parameters such as ventilation rate, occupant activities, etc. The tools we have developed will allow us to generate a parameterized database of mass-transfer coefficients for use in improving indoor air quality models. Relevant journal articles: Morrison et al., 2006, Morrison and Wiseman, 2006