Air pollution and associated respiratory morbidity in Delhi

Abstract

As a rapidly expanding centre of government, trade, commerce and industry, Delhi, the Indian capital, presents an instructive location for studying the possible association between air pollution and adverse health effects. This study tries to determine the association, if any, between the air pollutants--sulphur dioxide, nitrogen dioxide, carbon monoxide, ozone, suspended particulate matter and respiratory suspended particulate matter--and daily variations in respiratory morbidity in Delhi during the years 2004--2005. Data analysis was based on the Generalized Additive Poisson regression model including a Lowess smoothing function for the entire patient population and subgroups defined by season. The best fitting lag period for each pollutant was found by testing its concentration at varying lags. The model demonstrated associations between daily visits and some of the pollutants (O3, NO2 and RSPM) but their strongest components were observed at varying lags. A single pollutant model showed that a 10 microg m(-3) rise in pollutant level led to statistically significant relative risks (RR): 1.033 for O3, 1.004 for NO2, 1.006 for RSPM. The effect of particulate was relatively low, presumably because unlike other pollutants, particulate matter is not a single pollutant but rather a class of pollutants. This study, continued on a long term basis, can provide guidelines for anticipation/preparedness in the management of health care and hospital admissions.

A rapid assessment of the impact of hazard reduction burning around Sydney, May 2016

“…All six found positive associations with SO 2 (two nonsignificant) that ranged from 0.13% to 8.2% compared with -0.5-22.5% for the previous estimates. Where there was adjustment for other pollutants (Cakmak, Dales & Judek, 2006b;Jayaraman & Nidhi, 2008;Leem et al, 1998), the estimates were reduced and remained significant in only one study (Cakmak, Dales & Judek, 2006b). …”

“…Papers published since (or not considered in) the EPA's 2008 review also reported positive (though not always statistically significant) single-pollutant associations for hospital admissions and emergency room visits for: (a) asthma (Bell, Levy & Lin (2008), Colais et al, 2009;Giovannini et al, 2010;Halonen et al, 2008;Jalaludin et al, 2008;Samoli et al, 2011a;Szyszkowicz, 2008;Ueda, Nitta & Odajima, 2010;Villeneuve et al, 2007) and (b) respiratory causes (Colais et al, 2009;Eilstein et al, 2004;Faustini et al, 2013;Granados-Canal et al, 2005;Giovannini et al, 2010;Jayaraman & Nidhi, 2008;Thach et al, 2010;Vigotti et al, 2010).…”

“…Where confounding by co-pollutants was assessed in the studies since the EPA (2008b) review, some robustness to adjustment was demonstrated for these respiratory health outcomes (Giovannini et al, 2010;Ueda, Nitta & Odajima, 2010;Halonen et al, 2008;Jalaludin et al, 2008;Jayaraman & Nidhi, 2008;Villeneuve et al, 2007). For example, Halonen et al (2008) found that NO 2 was a strong and independent predictor of asthma emergency room visits in children in Finland.…”

“…There were no multicity studies that examined multipollutant models, and the single-city study multipollutant results were not reviewed. A further three studies have been added to APED since (Leem et al, 1998;Jayaraman & Nidhi, 2008;Chang, Hsia & Chen, 2002), another two meeting the criteria (Wong et al, 2010a;Cakmak, Dales & Judek, 2006b) were identified in the literature search, and another one later (Chen et al, 2010b). All six found positive associations with SO 2 (two nonsignificant) that ranged from 0.13% to 8.2% compared with -0.5-22.5% for the previous estimates.…”

Characteristics of the Ozone Pollution and its Health Effects in India

“…51 Jayaraman et al in Delhi showed that a 10-microgram rise in O 3 led to increase in respiratory morbidity (RR = 1.03). 52 …”