A Comparison of Four Gravimetric Fine Particle Sampling Methods

Abstract

A study was conducted to compare four gravimetric methods of measuring fine particle (PM 2.5 ) concentrations in air: the BGI, Inc. PQ200 Federal Reference Method PM 2.5 (FRM) sampler; the Harvard-Marple Impactor (HI); the BGI, Inc. GK2.05 KTL Respirable/Thoracic Cyclone (KTL); and the AirMetrics MiniVol (MiniVol). Pairs of FRM, HI, and KTL samplers and one MiniVol sampler were collocated and 24-hr integrated PM 2.5 samples were collected on 21 days from January 6 through April 9, 2000. The mean and standard deviation of PM 2.5 levels from the FRM samplers were 13.6 and 6.8 µg/m IMPLICATIONSBias in measurements of personal, indoor, and ambient air fine particle levels (PM 2.5 ) due to the sampling method may obscure relationships among personal, indoor, and ambient concentrations. The results from this intercomparison study show that the FRM (an ambient sampler), the HI (an indoor and ambient sampler), and the KTL (a personal sampler) provide comparable measures of PM 2.5 and can be used to evaluate ambient concentrations without substantial concern over bias in the results. The results indicate some concern about proportional bias in the measurements from the MiniVol. In some situations, the errors-in-variables problem with linear regression observed in this study may have important implications for determining regulatory equivalence of these PM 2.5 samplers.terms were 0.96 or greater between all pairs of samplers, and regression root mean square error terms (RMSE) were 1.65 µg/m 3 or less. These results suggest that the MiniVol will underestimate measurements made by the FRM, the HI, and the KTL by an amount proportional to PM 2.5 concentration. Nonetheless, these results indicate that all of the sampler types are comparable if ~10% variation on the mean levels and on individual measurement levels is considered acceptable and the actual concentration is within the range of this study (5-35 µg/m 3 ).

Short-Term Traffic-Related Exposures and Biomarkers of Nitro-PAH Exposure and Oxidative DNA Damage

“…PM 2.5 was collected on a 37-mm Teflon filter (with a pore diameter of 2 µm) after passing through a precision-machined cyclone pre-selector to remove particles greater than 2.5 µm aerodynamic diameter. The method was consistent with the EPA PQ200 Federal Reference Method [31–32]. Personal exposures were assigned to individual participants as a weighted average of the time the participant reported spending in each work location.…”

Characterization of Endotoxin Collected on California Dairies Using Personal and Area-Based Sampling Methods

“…with a cut point of 2.5 µm an airflow of 3.5 L/min, which has been shown by other studies to have good agreement with the PQ200 (BGI Inc.) Federal Reference Method PM 2.5 sampler, (31) was used to collect PM 2.5 . Teflon 37-mm Millipore filters with a pore size of 0.45 µm (FHLP03700; Fisher, Pittsburgh, Pa.) were used to collect the particles from the cyclone sampler.…”

Occupational exposure to particulate matter and endotoxin for California dairy workers

“…A GK2.05SH (KTL) cyclone sampler (BGI Inc., Waltham, MA) with a cut point of 2.5 m at an air flow of 3.5 l/min, which has been shown by other studies to have good agreement with the PQ200 (BGI Inc.) Federal Reference Method PM 2.5 sampler (Yanosky and Macintosh, 2001;Majestic et al, 2008), was used to collect PM 2.5 . Teflon 37 mm Millipore filters with a pore size of 0.45 m (Fisher Scientific, FHLP03700, Waltham, MA) were used.…”