The results of this study contribute to the evidence of an association of several correlated gaseous and particulate pollutants, including ozone, NO2, CO, PM, and organic carbon, with specific respiratory conditions.

BackgroundDisproportionate life stress and consequent physiologic alteration (i.e., immune dysregulation) has been proposed as a major pathway linking socioeconomic position, environmental exposures, and health disparities. Asthma, for example, disproportionately affects lower-income urban communities, where air pollution and social stressors may be elevated.ObjectivesWe aimed to examine the role of exposure to violence (ETV), as a chronic stressor, in altering susceptibility to traffic-related air pollution in asthma etiology.MethodsWe developed geographic information systems (GIS)–based models to retrospectively estimate residential exposures to traffic-related pollution for 413 children in a community-based pregnancy cohort, recruited in East Boston, Massachusetts, between 1987 and 1993, using monthly nitrogen dioxide measurements for 13 sites over 18 years. We merged pollution estimates with questionnaire data on lifetime ETV and examined the effects of both on childhood asthma etiology.ResultsCorrecting for potential confounders, we found an elevated risk of asthma with a 1-SD (4.3 ppb) increase in NO2 exposure solely among children with above-median ETV [odds ratio (OR) = 1.63; 95% confidence interval (CI), 1.14–2.33)]. Among children always living in the same community, with lesser exposure measurement error, this association was magnified (OR = 2.40; 95% CI, 1.48–3.88). Of multiple exposure periods, year-of-diagnosis NO2 was most predictive of asthma outcomes.ConclusionsWe found an association between traffic-related air pollution and asthma solely among urban children exposed to violence. Future studies should consider socially patterned susceptibility, common spatial distributions of social and physical environmental factors, and potential synergies among these. Prospective assessment of physical and social exposures may help determine causal pathways and critical exposure periods.

A large scale study of human exposure to nitrogen dioxide (NO2) was conducted in the Los Angeles Basin, the only metropolitan area in the United States that exceeds the NO2 NAAQS. Data are available for a population representative sample of 482 households and 682 individuals. Personal exposures, as well as indoor and outdoor home levels, were monitored using passive time-integrating filter badges. Monitoring extended over a one-year period (May 1987 to May 1988), with each individual providing two consecutive days of data. Information was also collected on activity patterns, household and personal characteristics, and spatial and temporal variables. This paper describes the study design, summarizes the sample characteristics and representativeness, and presents the distribution of personal, indoor, and outdoor NO2 concentrations recorded by the monitors. Over the entire sample, median personal and outdoor levels were 35 ppb; median indoor levels were 24 ppb. Personal exposures for those in homes with gas ranges with pilot lights average 10 ppb greater than those with electric ranges, and 4 ppb greater than those with gas ranges without pilot lights. Forty percent of the variation in indoor concentrations is explained by outdoor levels; 59 percent of the variation in personal exposures is explained by indoor levels; and 48 percent of the variation in personal exposures is explained by outdoor levels.

Substantial evidence supports an association of particulate matter ( PM ) with cardiorespiratory illnesses, but little is known regarding characteristics of PM that might contribute to this association and the mechanisms of action. The Atlanta superstation sponsored by the Electric Power Research Institute as part of the Aerosol Research and Inhalation Epidemiology Study ( ARIES ) study is monitoring chemical composition of ambient particles by size fraction, as well as a comprehensive suite of other pollutants, at a site in downtown Atlanta during the 25 -month period, August 1, 1998 ± August 31, 2000. Our investigative team is making use of this unique resource in several morbidity studies, called the``Study of Particulates and Health in Atlanta ( SOPHIA ) ''. The study includes the following components: ( 1 ) a time series investigation of emergency department ( ED ) visits for the period during which the superstation is operating; (2) a time series investigation of ED visits during the 5 years prior to implementation of the superstation; and ( 3 ) a study of arrhythmic events in patients equipped with automatic implantable cardioverter defibrillators ( AICDs ) for the period January 1, 1993 ± August 31, 2000. Thirty -three of 39 Atlanta area EDs are participating in the ED studies, comprising over a million annual ED visits. In this paper, we present initial analyses of data from 18 of the 33 participating EDs. The preliminary data set includes 1,662,713 ED visits during the pre -superstation time period and 559,480 visits during the superstation time period. Visits for four case groupings Ð asthma, chronic obstructive pulmonary disease ( COPD ) , dysrhythmia, and all cardiovascular diseases ( CVDs ) combined Ð have been assessed relative to daily air quality indices, controlling for long -term temporal trends and meteorologic variables, using general linear models, generalized estimating equations and generalized additive models. Single -pollutant models predicting case visitation rates using moving averages of 0 -, 1 -, and 2 -day lagged air quality variables were run. For the pre -superstation period, PM 10 ( 24-h ) , ozone ( 8-h ) , SO 2 ( 1-h ) , NO 2 ( 1-h ) and CO ( 1-h ) were studied. For the first 12 months of superstation operation, the following air quality variables of a priori interest were available: ozone ( 8-h ) , NO 2 ( 1-h ) , SO 2 ( 1-h ) , CO ( 1-h ) , and 24 -h measurements of PM 10 , coarse PM ( PM 2.5 ± 10 m ) , PM 2.5 , polar VOCs, 10 ± 100 nm particulate count and surface area, and in the PM 2.5 fraction: sulfates, acidity, water -soluble metals, organic matter ( OM ) , and elemental carbon ( EC ) . During the pre -superstation time period, statistically significant, positive associations were observed for adult asthma with ozone, and for COPD with ozone, NO 2 and PM 10 . During the superstation time period, the following statistically significant, positive associations were observed: dysrhythmia with CO, coarse PM, and PM 2.5 EC; and all CVDs with CO, PM 2.5 EC and PM 2.5 OM. While ...

Needleman, H. L.; Gunnoe, C.; Leviton, A.; Reed, R.; Peresie, H.; Maher, C.; Barrett, P. N. Engl. Continuous analyzers for NO, NO2, and HONO were used to study the production and decay of these gases in two indoor air quality research houses, using unvented gas space heaters and ranges as combustion sources. In agreement with previous studies, indoor HONO concentrations were elevated during unvented combustion. Peak (15-min) levels up to 100 ppb HONO and 24-h averages as high as 40 ppb were measured. The observed kinetics suggest the secondary formation of HONO, possibly as a result of heterogeneous reactions involving NOz, in addition to primary production of HONO during combustion.