Report of the particulate matter research strategies workshop, park city, utah, april 29-30, 1996

An informal one-and-a-half-day workshop devoted to research needs on the health effects of airborne particulate matter (PM) was held in Park City, Utah, on April 29 and 30,1996, in conjunction with the Second Colloquium on Particulate Air Pollution and Health at Park City, Utah, on May 1-3,1996. The objective of the workshop was to prepare a holistic assessment of knowledge gaps and research opportunities for presentation at the penultimate session of the colloquium. The workshop reviewed the research progress made since the first PM colloquium (Irvine, California, January 1994) and the findings of recent major reviews of the PM literature by the World Health Organization-European Region, the U.K. Health Department, the National Institute of Public Health in the Netherlands, and the U.S. Environmental Protection Agency. It then discussed (1) the nature of ambient PM, (2) population segments at special risk, (3) the nature of the health effects of concern, (4) the sources of ambient air PM, and (5) the implications of ambient air PM health effects on occupational exposure limits and occupational cohorts. The workshop concluded that: A primary focus for fuaher research should be on accumulation mode aerosol with the objective of disentangling the roles of its chemical constituents, as well as their interactive effects with each other and with coexisting gaseous criteria pollutants. Research is also urgently needed on the health effects of both the coarse-mode PM₁₀ and the ultrafine particles in the nuclei-mode aerosol. There should be a continued focus on infants, the elderly, and people with preexisting cardiopulmonary diseases. Further development and validation of animal models for human sensitive groups warrants high priority. Validated animal models are needed for target human populations in order to investigate: (1) the roles of specific constituents of PM mixtures, (2) the roles of exposure concentrations and durations on responses, (3) some of the risk factors that predispose individuals to be responsive to PM exposures, and (4) physiological, biochemical, molecular, and pathological correlates of mortality, tissue and organ damage, and chronic disease development.