Epidemiological Studies Confirmed by Clinical Research
Key epidemiologic studies on particles have been confirmed by cutting edge new research on human volunteers.
EPA researchers Dr. Andrew Ghio and Dr. Robert Devlin sought toxicological confirmation of the epidemiological studies of C. Arden Pope in the Utah Valley in the late 1980’s and early 1990’s that reported associations between particles and elementary school absences, hospital admissions for respiratory problems, and mortality.
Researchers obtained PM filters from the period when the Utah Valley steel mill was open, during closure, and after re-opening. They instilled extracts of the filters in the lungs of nonsmoking human volunteers, and then washed the lungs of these subjects.
“Exposure to aqueous extracts of PM collected before closure and after reopening of the steel mill provoked a greater inflammatory response relative to PM extract acquired during the plant shutdown. This is the first demonstration that pulmonary effects after experimental exposure of humans to PM can correlate with health outcomes observed in epidemiologic studies of the same material under normal exposure conditions,” conclude the researchers, who also pointed to the importance of metals in PM in stimulating a biologic response.
The article and an accompanying editorial appear in the second of two August issues of the American Journal of Respiratory and Critical Care Medicine. (Am J Res Crit Care Med No. 164, pp. 704-708, August 2001).
Dr. William Beckett of the University of Rochester notes in his editorial, that “Because the steel mill produced more than 80% of the fine particulate matter sampled in the Utah Valley during its years of operation, it seems safe to conclude that the presence of more particles in the air, as well as something different about the makeup of those steel mill furnace combustion particles, is capable of inducing a significantly greater inflammatory response in the lungs of even healthy adults.”
The American Thoracic Society [ajrccm.atsjournals.org/] publishes the abstract online.
