Particulate Matter

Dr John Godleski and colleagues at Harvard School of Public Health conducted an exploratory study to test the effects of particulate matter exposure in dogs, which share many features of the human cardiovascular system. The investigators hypothesized that particulate matter might affect the animals' cardiac function, leading to arrhythmia, and might induce inflammatory responses and changes in pulmonary mechanical measurements. Twelve dogs were exposed to concentrated ambient particles (CAPs) that were 30 times their level in ambient Boston air.

Drs. Douglas Dockery at the Harvard School of Public Health and C. Arden Pope III at Brigham Young University speculated that exposure to PM might lead to a transient drop in blood oxygenation, which might have serious consequences in humans with heart or lung problems. The investigators designed a study to increase the possibility of observing PM effects by testing a potentially at-risk group (the elderly) at a time of year that historically had experienced relatively high levels of PM (the winter).

Communication 5 contains proceedings of a workshop held in Cambridge, MA, December 3–4 1996. Presentations included: Current Understanding of the Health Effects of Particles and the Characteristics That Determine Dose or Effect; Particle Formation in Combustion; The EPA Particle Emissions Testing Procedure; Characterizing Particulate Matter in Motor Vehicle Exhaust; Atmospheric Aerosol Transformation; Generating Particles for Laboratory Studies; and Issues and Research Needs for Particle Characterization.

The Phase I.A Report of the Particle Epidemiology Evaluation Project. The Health Effects Institute began the Particle Epidemiology Evaluation Project in 1994 to evaluate the emerging epidemiologic evidence of a relation between particulate air pollution and daily mortality. In Phase I.A, Drs. Jonathan M. Samet and Scott L. Zeger and their colleagues at the Johns Hopkins University School of Hygiene and Public Health (1) reconstructed from original sources the data set for Philadelphia used in earlier studies and confirmed previous numerical results from analyzing these data; (2) developed an analytic approach (including new statistical methods) based on the Philadelphia data set; and (3) applied this approach to data sets for six locations: Philadelphia; Utah Valley; St. Louis, MO; Eastern Tennessee; Birmingham, AL; and Santa Clara County, CA.