September 25, 2009
Colloquium Topic: Medical Geology: Dust Exposure and Potential Health Risks in The Middle East
In the Middle East, dust & sand storms are a persistent problem and can deliver significant amounts of micro-particulates via inhalation into the mouth, nasal pharynx, & lungs due to the fine size and abundance of these micro-particulates. The chronic and acute health risks of this dust inhalation have not been well studied nor has the dust been effectively characterized as to its chemical composition, mineral content, or microbial flora. Scientific experiments were designed to study the Kuwaiti & Iraqi dust as to its physical, chemical, and biological characteristics and for its potential to cause adverse health effects. First, dust samples from different locations were collected & processed & exposure data collected. Initial chemical & physical characterization of each sample including particle size distribution & inorganic analysis was conducted, followed by characterization of biologic flora of the dust, including bacteria, fungi and viruses. Initial data indicates that the mineralized dust is composed of CaCO3 in a coating over a matrix of metallic silica crystals containing a variety of trace metals constituting ~1% of the PM10 by weight. The particles also consist of ~1% bioavailable Al and reactive Fe each. Microbial analysis reveals a significant biodiversity of bacterial, fungi, and viruses of which ~30% are known pathogens. The level of total suspended particle mass along with environmental & physiological conditions present constitute an excessive exposure to micro-particulates including PM 2.5 & the potential for long-term adverse health effects. These data suggest that the level of dust exposure coupled with the microbial & metal content could constitute a significant health risk. When taken with other existing work suggest that further immediate research is warranted to provide insight into potential human health risks both acute and chronic.
Colloquium Speaker: Capt. Mark B. Lyles
CAPT Mark B. Lyles, MS, DMD, Ph.D. is currently the Deputy to the Special Assistant to the Surgeon General for Research Program Integration & Mission Development (M00) at the U.S. Navy Bureau of Medicine and Surgery, in Washington, D.C. He also is TAD to the Army’s Combat Casualty Care Research Detachment at Fort Detrick as the Navy Liaison. Dr. Lyles attended Murray State University earning his B.A. in Chemistry & Cell Physiology in 1978 followed by both an A.S.- B.S. degree in Chemical Technology and Cell Biology respectively in 1981. He earned a M.S. degree in Analytical Chemistry & an Ed.S. degree in Higher Education in 1982 conducting his research at the National Center of Toxicological Research EPA / FDA in Pine Bluff, AK. In 1981, he was a Graduate Fellow in both Physiology and Toxicology at the University of Louisville and in 1982, entered the College of Dentistry earning his D.M.D. in 1986. Upon graduation, Dr. Lyles was commissioned in the U.S. Navy having assignments at the 12th Dental Company, the 22nd Marine Expeditionary Unit / Special Operations Contingency Force (MARG 4/87 ‘World’s Angriest Dog’ and ‘The Battleship’ USS New Jersey BB62. Upon his discharge from active duty in 1991, Dr. Lyles was awarded a National Institute of Dental Research (NIDR) Dentist-Scientist Award, attending the University of Texas Health Science Center at San Antonio for training in Oral and Maxilofacial Surgery and for his Ph.D. in Cellular and Structural Biology in 2001. Dr. Lyles is the founder (1994) and Chief Scientific Officer of Materials Evolution and Development U.S. A., Inc. He was voluntarily recalled to active duty in August of 2003 and was assigned to the Naval Institute for Dental and Biomedical Research as Head, Advanced Laboratory Sciences. In 2004, CAPT Lyles deployed to Kuwait/Iraq for Operation Sandman & Operation Sandbox in support of OIF. CAPT Lyles has published over 100 scientific articles and abstracts and has over 40 issued or pending national and international patents in the fields of biomaterials, tissue engineering, drug delivery systems, sunscreens, diagnostics, etc. He is the 1994 winner of the Walter Lorenz Research Award from the American College of Oral and Maxillofacial Surgeons and selected the 1997 Imagineer of the Year by the Mind Science Foundation for his work in condensable dental composite materials (credited for the creation of the field of Ceromers). In 2008, Dr. Lyles was awarded the Carl A. Schlack Award by the Association of Military Surgeons of the U. S. for outstanding contributions in dental research and education. Additionally, he was selected by the Navy Astronaut Selection Board for evaluation by NASA. He completed a M.A. in National Defense and Strategic Studies at the Naval War College in 2008. CAPT Lyles continues to pursue his research interests in environmental toxicology and dusty agents and is currently involved in projects investigating the health effects of airborne micro-particulates from around the world. His expertise is in biomaterials and biomedical / tissue engineering with expertise in medical devices, wounds and wound healing.