Indoor, outdoor, and personal exposure monitoring of particulate air pollution: the Baltimore elderly epidemiology-exposure pilot study

Williams, Ron; Creason, John P.; Zweidinger, Roy B.; Watts, Randall R; Sheldon, Linda; Shy, Carl M.

doi:10.1016/s1352-2310(00)00209-0

Cited by 77 publications

(45 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This will lead to increased imprecision when comparing pDR results with gravimetric results. Our estimate of the precision (mean RSD) of the pDR was 17%, somewhat larger than the values around 10% found by other studies (Liu et al 2002;Williams et al 2000). …”

Section: Discussioncontrasting

confidence: 78%

“…To the extent that this density differs from the density of the particles being sampled, this will lead to a bias in comparisons with gravimetric results. Several recent studies indicate that the bias associated with the pDR is on the order of 50-70% higher than gravimetric measures (Liu et al 2002;Williams et al 2000). This is consistent with the fact that the density of the calibration aerosol is 2.6, whereas the average density of ambient aerosols appears to be of the order of 1.55 (Sioutas et al 2000).…”

Section: Children's Health | Particles In Inner-city Homessupporting

confidence: 70%

See 1 more Smart Citation

Particle concentrations in inner-city homes of children with asthma: the effect of smoking, cooking, and outdoor pollution.

Wallace

Mitchell

O’Connor

et al. 2003

Environ Health Perspect

209

175

View full text Add to dashboard Cite

show abstract

Section: Discussioncontrasting

confidence: 78%

Section: Children's Health | Particles In Inner-city Homessupporting

confidence: 70%

Particle concentrations in inner-city homes of children with asthma: the effect of smoking, cooking, and outdoor pollution.

Wallace

Mitchell

O’Connor

et al. 2003

Environ Health Perspect

209

175

View full text Add to dashboard Cite

show abstract

“…Concurrent with our studies, several other studies employing similar instrumentation were performed. [13][14][15] Findings from these studies will be discussed and compared with our findings in the Discussion section of this paper.…”

Section: Discussionmentioning

confidence: 87%

“…The MIE has been fairly widely used in environmental studies recently with reasonable results except for humidity-related overestimates at RH levels greater than 60-70%. 13,14,23,24 A recent study 25 of the MIE response to aerosols of known composition and size distribution indicated that, for NaCl and (NH 4 ) 2 SO 4 aerosols, the MIE was within a factor of 2 of the gravimetric results, but for peanut oil aerosols (when corrected for density), it read low by 50-80%.…”

Section: Limitations Of Instrumentationmentioning

confidence: 98%

Continuous Monitoring of Ultrafine, Fine, and Coarse Particles in a Residence for 18 Months in 1999-2000

Wallace

Howard-Reed

2002

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

Continuous monitors were employed for 18 months in an occupied townhouse to measure ultrafine, fine, and coarse particles; air change rates; wind speed and direction; temperature; and relative humidity (RH). A main objective was to document short-term and long-term variation in indoor air concentrations of size-resolved particles (0.01-20 µm) caused by (1) diurnal and seasonal variation of outdoor air concentrations and meteorological variables, (2) indoor sources such as cooking and using candles, and (3) activities affecting air change rates such as opening windows and using fans. A second objective was to test and compare available instruments for their suitability in providing real-time estimates of particle levels and ancillary variables.Despite different measuring principles, the instruments employed in this study agreed reasonably well for particles less than 10 µm in diameter. The three instruments measuring fine and coarse particles (aerodynamic diameter between 0.3 and 20 µm) agreed to within 30% in their overall estimates of total volume. Two of these instruments employed optical scattering, and the third used an aerodynamic acceleration principle. However, several lines of evidence indicated that the instrument employing aerodynamic acceleration overestimated concentrations for particle diameters greater than 10 µm. A fourth instrument measuring ultrafine and accumulationmode particles (0.01-1 µm) was operated with two different inlets providing somewhat different particle size ranges. The two inlets agreed in the ultrafine region (<0.1 µm) but diverged increasingly for larger particles (up to 0.445 µm).Indoor sources affecting ultrafine particle concentrations were observed 22% of the time, and sources affecting fine and coarse particle concentrations were observed 12 and 15% of the time, respectively. When an indoor source was operating, particle concentrations for different sizes ranged from 2 to 20 times the average concentrations when no indoor source was apparent. Indoor sources, such as cooking with natural gas, and simple physical activities, such as walking, accounted for a majority (50-90%) of the ultrafine and coarse particle concentrations, whereas outdoor sources were more important for accumulation-mode particles between 0.1 and 1 µm in diameter. Averaged for the entire year and including no periods when indoor sources were apparent, the number distribution was bimodal, with a peak at ~10 nm (possibly smaller), a shallow minimum at ~14 nm, and a second broad peak at ~68 nm. The volume distribution was also bimodal, with a broad peak at ~200 nm, a minimum at ~1.2 µm, and then an upward slope again through the remaining size fractions.A database was created on a 5-min averaging time basis. It contains more than 90,000 measurements by two of the instruments and approximately 30,000 by the two optical scattering instruments. About 4500 hour-long average air change rates were also calculated throughout the year using a dedicated gas chromatograph with electron capture detection (GC/E...

show abstract

“…Results from an earlier study conducted by our group in Baltimore, Maryland, indicated that increased levels of fine particles were associated with decreased heart rate variability (HRV ) among elderly nonsmokers, especially among those with some indication of preexisting cardiovascular disease ( Liao et al, 1999, Williams et al, 2000a . Other researchers have recently reported similar associations between airborne particulate matter and increased pulse rate ( Peters et al, 1999;Pope et al, 1999a ) , decreased HRV (Pope et al, 1999b ), and occurrence of cardiac arrhythmia ( Peters et al, 2000 ).…”

Section: Introductionmentioning

confidence: 99%

Particulate matter and heart rate variability among elderly retirees: the Baltimore 1998 PM study

Creason

Neas

Walsh

et al. 2001

J Expo Sci Environ Epidemiol

Self Cite

150

View full text Add to dashboard Cite

This study investigates the relationship between ambient fine particle pollution and impaired cardiac autonomic control in the elderly. Heart rate variability ( HRV ) among 56 elderly ( mean age 82 ) nonsmoking residents of a retirement center in Baltimore County, Maryland, was monitored for 4 weeks, from July 27 through August 22, 1998. The weather was seasonally mild ( 63 ± 848F mean daily temperature ) with low to moderate levels of fine particles ( PM 2.5 < 50 g / m 3 ) . Two groups of approximately 30 subjects were examined on alternate days. A spline mixed -effects model revealed a negative relationship between outdoor 24 -h average fine particulate matter ( PM 2.5 ) and high -frequency ( HF ) HRV that was consistent with our earlier Baltimore study for all but 2 days. These 2 days were the only days with significant precipitation in combination with elevated PM 2.5 . They were also unusual in that back -trajectory of their air masses was distinctly different from those on the other study days, emanating from the direction of rural Pennsylvania. Mixed -effects analysis for all 24 study days showed a small negative association of outdoor PM 2.5 with HF HRV ( À 0.03 change in log [ HF HRV ] for a 10 g / m 3 increment in PM 2.5 ) after adjustment for age, sex, cardiovascular status, trend, maximum temperature, average dew point temperature, random subject intercepts, and autocorrelated residuals. After excluding study days 4 and 5, this association was strengthened ( À 0.07 change in log [ HF HRV ] for 10 g / m 3 PM 2.5 , 95% CI À 0.13 to À 0.02 ) and was similar to that obtained in an earlier study ( À 0.12 change in log [ HF HRV ] for a 10 g / m 3 increment in outdoor PM 2.5 , 95% CI À 0.24 to À 0.00 ) [ Liao D., Cai J., Rosamond W.D., Barnes R.W., Hutchinson R.G., Whitsel E.A., Rautaharju P., and Heiss G. Cardiac autonomic function and incident coronary heart disease: a population -based case -cohort study. The ARIC Study. Atherosclerosis Risk in Communities Study. Am J Epidemiol 1997: 145 ( 8 ) : 696 ± 706 ] . Acute ( 1 to 4 h ) previous PM 2.5 exposure did not have a stronger impact than the 24 -h measure. A distributed lag model incorporating the six preceding 4 -h means also did not indicate any effect greater than that observed in the 24 -h measure. This study is consistent with earlier findings that exposures to PM 2.5 are associated with decreased HRV in the elderly.

show abstract

Indoor, outdoor, and personal exposure monitoring of particulate air pollution: the Baltimore elderly epidemiology-exposure pilot study

Cited by 77 publications

References 8 publications

Particle concentrations in inner-city homes of children with asthma: the effect of smoking, cooking, and outdoor pollution.

Particle concentrations in inner-city homes of children with asthma: the effect of smoking, cooking, and outdoor pollution.

Continuous Monitoring of Ultrafine, Fine, and Coarse Particles in a Residence for 18 Months in 1999-2000

Particulate matter and heart rate variability among elderly retirees: the Baltimore 1998 PM study

Contact Info

Product

Resources

About