Philip N. Smith - Research
Current
Research
Air Issues
Current
large-scale beef production operations in the United States concentrate large
numbers of cattle onto feedlots prior to slaughter. Beef cattle production is augmented
by widespread use of growth promoters. As a result, anabolic steroids are
excreted into the environment. By their very nature, hormones are biologically
active at exceedingly low concentrations and influence growth, development, and
reproduction in all vertebrates. Synthetic hormones are more resistant to
microbial degradation and persist in the environment longer than natural
hormones. Run-off from confined animal feeding operations (CAFOs) is typically considered
the primary route of transport, and developmental and reproductive effects have
been documented among aquatic organisms in surface waters near CAFOs. Our
research will answer the questions, “Are anabolic hormones transported from
feedlots by wind, and if so, are quantities sufficient to result in adverse
effects?”
Water Issues
Water
quality and availability are also critical issues in Texas and throughout the
world. Dr. Smith has recently become involved in efforts to integrate
environmental research and educational programs focused on water and water
quality. For example, the critical water quality issues of Marion County, Texas
and the greater Caddo Lake watershed are being addressed through a partnership
with the Jeffersonian Institute in Jefferson Texas. This applied environmental
research program provides extensive opportunities for the education of
scientists, teachers, and citizens of the broader community that will result in
a science-based understanding and appreciation of wetlands and their fauna.
Integrating research with educational programs for students provides the
contextual basis for conservation of natural resources, long-term environmental
biology research, and the development of environmentally conscientious and
responsible scientists, teachers and citizens. These efforts can be leveraged
to facilitate rural economic development and improve quality of life. In
addition to examining water issues in East Texas, Dr. Smith is examining water
issues in the Southern High Plains. He and his students are interested in
developing sentinels of ecological health for the unique playa lakes of West
Texas. Current work is focused on pesticide runoff and the effects of
unregulated pesticide formulation ingredients on playa-dependent organisms.
Past Research
A great deal of Dr. Smith’s research at TIEHH has focused on the ecological effects of compounds used for military-related purposes like perchlorate and HMX. In its various salt formulations (i.e., sodium perchlorate, ammonium perchlorate, etc.), perchlorate is used as an oxidizer and makes up a high percentage of the total weight of various solid rocket formulations and can also be found in flairs, pyrotechnics, and even air-bags. In the environment, perchlorate is an extremely water soluble anion that can persist for decades. It is readily taken up by plants, and can alter thyroid hormone concentrations in exposed humans and wildlife. HMX is an explosive formulation that is commonly found and military training sites across the country.
Dr. Smith has conducted research related to perchlorate and explosives. That work was funded by the Strategic Environmental Research and Development Program (SERDP), the United States Department of Agriculture (USDA), and others. Much of the perchlorate research is included in a book entitled Perchlorate Ecotoxicology that Dr. Smith and Dr. Ron Kendall published with their colleagues in 2006. Additionally, Dr. Smith has conducted research to examine the energetic costs of various anthropogenic and natural stressors in macroinvertebrates and aquatic vertebrates inhabiting playa lakes in the Southern Great Plains.
Also of particular research interest to Dr. Smith is the role of persistent organic pollutants, other industrial chemicals, and pesticides in canine carcinogenesis.
Other
projects are described below:
2010 Growth
Promoters, Wind, and Human/Ecological Health
2009 Assessment of Airborne
Anabolic Hormones from Confined Animal Feeding Operations
2008 Effects of Perchlorate in Waters from NWIRP,
McGregor on a Native Amphibian Species
Assessment of Airborne Anabolic Hormones from Confined Animal Feeding Operations
2008 Effects of Perchlorate in Waters from NWIRP,
McGregor on a Native Amphibian Species
Assessment
of Airborne Anabolic Hormones from Confined Animal Feeding Operations
2007 Ecological Risk Assessment of Mercury in the
Effects of PAHs
on Avian Species, and HMX Exposure in a Hind-gut Fermenting Species, the
Prairie vole
2006 Playa Wetland Environmental Stress Effects on
Indigenous Fairy Shrimps
Bioavailability
and Avoidance of HMX in a Terrestrial Amphibian
SEQ CHAPTER \h
\r 1Evaluating
Metabolic Induction and Reproductive Toxicity of TNT in Peromyscus
maniculatus
2005 Bioavailability
and Avoidance of HMX in a Terrestrial Amphibian
SEQ CHAPTER \h \r 1Evaluating Metabolic
Induction and Reproductive Toxicity of TNT in Peromyscus
maniculatus
2004 Acute effects of the explosive compound HMX
on avian and reptilian species
Reproductive toxicity of HMX in birds and reptiles
2003 Effects of perchlorate on metabolic rates in
endothermic organisms
Effects of perchlorate on Wood Ducks (Aix sponsa)
Immunotoxicological responses
of amphibians exposed to perchlorate
Bosque and Leon
River Watershed Study; Terrestrial ecotoxicology of
perchlorate in the
Evaluating exposure and effects of perchlorate on
mammalian (including cattle), avian, and reptilian wildlife species2002
2002 Perchlorate
accumulation and toxicity from consumption of food crops grown with
contaminated irrigation water
2001 Raccoons as a sentinel of environmental
perchlorate contamination
Development
and evaluation methods to accurately determine avian habitat use and
habitat-specific behaviors in agricultural systems
1997 Raccoons (Procyon lotor) as sentinels
for polychlorinated biphenyl and heavy metal exposure and effects at the
Paducah Gaseous Diffusion Plant, McCracken County, KY
1996 Rodents as biomonitors
of PCB and metal contamination at the
I am grateful to have received funding from the
following agencies:
- USDA
- NSF
Ensafe, Inc. - Norman Hackerman
- Strategic
Environmental Research and Development Program
- US Corps of Engineers
- Caddo Lake Institute
·
US Environmental
Protection Agency
·
Bechtel Jacobs, Inc.
· Martin Energy systems, Inc.
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