Intercomparison of five PM10 monitoring devices and the implications for exposure measurement in epidemiological research

Abstract

Five different instruments for the determination of the mass concentration of PM 10 in air were compared sideby-side for up to 33 days in an undisturbed indoor environment: a tripod mounted BGI Inc. PQ100 gravimetric sampler with a US EPA certi®ed Graseby Andersen PM 10 inlet; an Airmetrics Minivol static gravimetric sampler; a Casella cyclone gravimetric personal sampler; an Institute of Occupational Medicine gravimetric PM 10 personal sampler; and two TSI Inc. Dustrak real-time optical scattering personal samplers. For 24 h sampling of ambient PM 10 concentrations around 10 mg m 23 , the estimated measurement uncertainty for the two gravimetric personal samplers was larger (y¡20%) compared with estimated measurement uncertainty for the PQ100/Graseby Andersen sampler (v¡5%). Measurement uncertainty for the Dustraks was lower (y¡15% on average) but calibration of the optical response against a reference PM 10 method is essential since the Dustraks systematically over-read PM 10 determined gravimetrically by a factor y2.2. However, once calibrated, the Dustrak devices demonstrated excellent functionality in terms of ease of portability and real-time data acquisition. Estimated measurement uncertainty for PM 10 concentrations determined with the Minivol were ¡5%. The Minivol data correlated well with PQ100/Graseby Andersen data (r~0.97, n~18) but were, on average, 23% greater. The reason for the systematic discrepancy could not be traced. Intercomparison experiments such as these are essential for assessing measurement error and revealing systematic bias. Application of two Dustraks demonstrated the spatial and temporal variability of exposure to PM 10 in different walking and transport microenvironments in the city of Edinburgh, UK. For example, very large exposures to PM 10 were identi®ed for the lower deck of a double-decker tour bus compared with the open upper deck of the same vehicle. The variability observed emphasises the need to determine truly personal exposure pro®les of PM 10 for quantifying exposure±response relationships for epidemiological studies.

The direct influence of ship traffic on atmospheric PM2.5, PM10 and PAH in Venice

“…Concentrations measured by the DustTrack Ò are generally higher than those found by gravimetric analysis (Kingham et al, 2006). Heal et al (2000) reported that the PM 10 measured with a DustTrack Ò was overestimated by a factor of 2.2 with respect to a reference gravimetric method. The PM 2.5 outdoor value recorded by the DustTrack Ò was overestimated by a factor of 3 according to Chung et al (2001).…”

Variation of Indoor Particulate Matter Concentrations and Association with Indoor/Outdoor Temperature: A Case Study in Rural Limpopo, South Africa

“…The calibration factor was obtained by comparing the continuous measurements to 24-hour gravimetric measurements sampled during the sampling period in the same households. This was done because previous studies that used the DustTrak [14][15][16][17][18][19][20][21][22] for photometric aerosol monitoring have indicated a significant overestimation of the particulate concentrations when compared to a reference gravimetric method. These studies were all conducted in various settings and compared to different reference methods.…”

Insights into Indoor/Outdoor PM Concentration Ratios due to Dust Storms in an Arid Region

“…Natural dust particles are very similar to the Arizona Dust used to calibrate the DustTrak (TSI, 1997), providing confidence for attaining a reasonable measurement of the PM concentration during dust events [16]. Data from the DustTrak can be corrected for more accurate mass concentrations [17][18][19][20][21][22]. In this study, the procedure of the real-time measurements included preliminary tests of the DustTrak readings through comparisons with records from a standard environmental PM monitor (Thermo Scientific TEOM ® 1405-DF) located in the center of Beer Sheva, which operates within the framework of the national air monitoring system.…”