Effects of Subchronic and Chronic Exposure to Ambient Air Pollutants on Infant Bronchiolitis

Abstract

Ambient air pollutant exposure has been linked to childhood respiratory disease, but infants have received little study. The authors tested the hypotheses that subchronic and chronic exposure to fine particulate matter (particulate matter < or = 2.5 microm in aerodynamic diameter (PM2.5)), nitrogen dioxide, carbon monoxide, and ozone increases risk of severe infant bronchiolitis requiring hospitalization. Study subjects were derived from linked birth-hospital-discharge records of infants born in 1995-2000 in the South Coast Air Basin of California. Cases with a hospital discharge for bronchiolitis in infancy were matched to 10 age- and gestational-age-matched controls. Exposures in the month prior to hospitalization (subchronic) and mean lifetime exposure (chronic) referenced to the case diagnosis date were assessed on the basis of data derived from the California Air Resources Board. In conditional logistic regression, only subchronic and chronic PM2.5 exposures were associated with increased risk of bronchiolitis hospitalization after adjustment for confounders (per 10-microg/m3 increase, adjusted odds ratio = 1.09 (95% confidence interval: 1.04, 1.14) for both). Ozone was associated with reduced risk in the single-pollutant model, but this relation did not persist in multipollutant models including PM2.5. These unique US data suggest that infant bronchiolitis may be added to the list of adverse effects of PM2.5 exposure.

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

“…Several studies have found an association between PM 2.5 and infant bronchiolitis, an important risk for hospitalization (Karr et al, 2007(Karr et al, , 2009a. Exposure to PM 2.5 has also been linked to low lung function in 4-year-old children in a birth cohort study in the Netherlands (Eenhuizen et al, 2012), supporting previously published studies that reported effects of PM 2.5 on lung function development, reviewed in Götschi et al (2008).…”

Air pollution and emergency admissions for cardiorespiratory diseases in Lisbon (Portugal)

“…5,16,23,29,32,48,64 However, some published studies found that, sometimes at low ambient O 3 levels, the relationship between various measures of morbidity and ozone concentration has a negative slope, that is, low levels of ozone appear to be more harmful than moderate values. [65][66][67] Revising the literature, Ritchie and Lenen 66 refer that no statistically significant effect for O 3 and various respiratory conditions was reported in studies undertaken in Hong Kong, London, Melbourne, Mexico, southern Ontario, Seattle, Sidney, St. John (New Brunswick), and Vancouver. The same authors found a statistically significant negative association for asthma and no relationship for other respiratory diseases on children in the Indianapolis Metropolitan Area.…”

Air pollution and respiratory diseases: ecological time series

“…13 Chronic and sub-chronic exposure to fine particulate matter, among other pollutants, was shown to be a risk factor for hospitalization due to acute bronchiolitis among children in California. 19 Using logistic regression, those authors showed that there was an association between exposure to PM 2.5 and the outcome of hospitalization due to acute bronchiolitis; and that an increase in PM 2.5 concentration of 10 µg/m 3 increased the odds of hospitalization by 9% (95% CI: 1.04-1.14). This allowed the authors to suggest that bronchiolitis was one of the adverse effects of exposure to Sheffield et al 21 in the United States found that a 7% decrease in PM 2.5 levels could result in savings of $ 15 million a year.…”