The 1999 Fresno Particulate Matter Exposure Studies: Comparison of Community, Outdoor, and Residential PM Mass Measurements

Abstract

Two collaborative studies have been conducted by the U.S. Environmental Protection Agency (EPA) National Exposure Research Laboratory (NERL) and National Health and Environmental Effects Research Laboratory to determine personal exposures and physiological responses to particulate matter (PM) of elderly persons living in a retirement facility in Fresno, CA. Measurements of PM and other criteria air pollutants were made inside selected individual residences within the retirement facility and at a central outdoor site on the premises. In addition, personal PM exposure monitoring was conducted for a subset of the participants, and ambient PM monitoring data were available for comparison from the NERL PM research monitoring platform in central Fresno. Both a winter (February 1-28, 1999) and a spring (April 19-May 16, 1999) study were completed so that seasonal effects could be IMPLICATIONS The Fresno PM exposure studies demonstrate the utility of measuring personal exposures and relevant stationary concentrations (at least residential, outdoor, and community) in conjunction with an epidemiology study. Longitudinal and seasonal effects were found to be important factors to consider in study design (the studies were conducted for a duration of 1 month in each of 2 seasons). These studies provide data to assist the EPA and other researchers in identifying potentially important exposure variables, as well as use in exposure analysis, modeling, and risk assessment activities.evaluated. During the spring study, a more robust personal exposure component was added, as well as a more detailed evaluation of physical factors, such as airexchange rate, that are known to influence the penetration of particles into the indoor environment. In this paper, comparisons are made among measured personal PM exposures and PM mass concentrations measured at the NERL Fresno Platform site, outside on the premises of the retirement facility, and inside selected residential apartments at the facility during the two 28-day study periods. The arithmetic daily mean personal PM 2.5 exposure during the winter study period was 13.3 µg/m 3 , compared with 9.7, 20.5, and 21.7 µg/m 3 for daily mean overall apartment, outdoor, and ambient (i.e., platform) concentrations, respectively. The daily mean personal PM 2.5 exposure during the spring study period was 11.1 µg/m 3 , compared with 8.0, 10.1, and 8.6 µg/m 3 for the daily mean apartment, outdoor, and ambient concentrations, respectively.

A population exposure model for particulate matter: case study results for PM2.5 in Philadelphia, PA

“…For example, Rojas -Bracho et al (2000) report that the mean personal PM 2.5 measurement for 17 adults with COPD in Boston was 21.6 g/m 3 with a range of 1-128 g/m 3 . However, Williams et al ( 2000a,b ) report a mean personal PM 2.5 concentration of 13.0 g/m 3 for elderly adults in Baltimore (n =23 ), and Evans et al (2000) report mean personal PM 2.5 concentrations of 13.3 and 11.1 g/m 3 for elderly adults in two studies in Fresno (n =24 and 12).…”

“…To better understand the relationship between personal exposures and stationary community measurements, human exposure field studies have been conducted, which measure both community PM concentrations and personal PM exposures. These PM exposure field studies have included population -based studies such as PTEAM and EXPOLIS (Clayton et al, 1993;Jantunen et al, 1998 ) and panel studies that target a subset of the population, such as the elderly ( Ebelt et al, 2000;Evans et al, 2000;Janssen et al, 2000;Sarnat et al, 2000;Williams et al, 2000a ).…”

Reduction and characterization of bioaerosols in a wastewater treatment station via ventilation

“…Airborne bacteria were incubated in Nutrient agar (BR, Aoboxing Biotech, Co., Beijing, China) at 30°C for 48 hr, and fungi were cultivated in Rose Bengal Medium (BR, Aoboxing Biotech Co., China) at 30°C for 7 days. Positive-hole correction was used to determine colony count concentrations (Andersen 1958;Macher 1989;Evans et al, 2000). Results were calculated as the geometric mean of the replicates, expressed as colony-forming units per cubic meter of air (CFU/m 3 ).…”

The Influence of Human Activity Patterns on Personal PM Exposure: A Comparative Analysis of Filter-Based and Continuous Particle Measurements

“…Participants usually opened windows rather than running HVAC systems to cool their homes. A complete description of the Fresno PM exposure study may be found in Evans et al 8 …”

“…8 Measurements have shown that personal PM concentrations are usually greater than community-based ambient PM concentrations in subjects who live active lifestyles and are exposed to select sources of particle exposures (environmental tobacco smoke, cooking aerosols, etc.). [9][10][11][12][13] Personal PM exposures are subject to large fluctuations …”