Coarse Particulate Matter and Hospitalization for Respiratory Infections in Children Younger Than 15 Years in Toronto: A Case-Crossover Analysis

Abstract

ABSTRACT. Objectives. The purpose of this study was to examine the association between ambient air pollution and hospitalization for respiratory infections among children who were younger than 15 years in Toronto during a 4-year period (1998 -2001).Methods. Exposures averaged during periods that varied from 1 to 7 days were used to assess the effects of air pollutants, including thoracic particulate matter (PM 10 ), fine (PM 2.5 ) and coarse (PM 10 -2.5 ) particulate matter, carbon monoxide (CO), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and ozone (O 3 ), on hospitalization for respiratory infections. A case-crossover design was used to calculate odds ratios for the hospitalization adjusted for daily weather conditions with an incremented exposure corresponding to the interquartile range in air pollution exposures.Results. When particulate matter and gaseous pollutants were mutually taken into account, the effect remained pronounced for PM 10 -2.5 in both boys and girls. The adjusted odds ratio for 6-day average exposure to PM 10 -2.5 with an increment of 6.5 g/m 3 was 1.15 (95% confidence interval: 1.02-1.30) for boys and 1.18 (95% confidence interval: 1.01-1.36) for girls. The effect also remained for PM 10 in boys and for NO 2 in girls. PM 2.5 , CO, SO 2 , and O 3 showed no significant effects on hospitalization for respiratory infection in both genders when other pollutants were taken into consideration.Conclusion. Our study suggested a detrimental effect of relatively low levels of ambient particulate matter and gaseous pollutants, especially coarse particulate matter and NO 2 , on hospitalization for respiratory infections in children. Pediatrics 2005;116:e235-e240. URL: www. pediatrics.org/cgi/doi/10.1542/peds.2004-2012; air pollution, coarse particulate matter, gaseous pollutants, hospitalization for respiratory infection, case-crossover analysis, risk assessment.ABBREVIATIONS. CO, carbon monoxide; SO 2 , sulfur dioxide; NO 2 , nitrogen dioxide; O 3 , ozone; PM 10 , thoracic particulate matter Ͻ10 m in aerodynamic diameter; PM 2.5 , fine particulate matter Ͻ2.5 m in aerodynamic diameter; TEOM, tapered element oscillating microbalance; PM 10 -2.5 , coarse particulate matter between 2.5 and 10 m in aerodynamic diameter; OR, odds ratio; CI, confidence interval; TSP, total suspended particles. L ower respiratory infection is a main cause of mortality and morbidity in children in developing countries. Morbidity from childhood respiratory infections is also high in developed countries. 1 Although respiratory infections in children are usually nonfatal in developed countries, they heavily burden the health care systems. 2 Additional progress in preventing the diseases will have a significant impact on children's health. 1 Although there is abundant evidence linking outdoor air pollution with respiratory symptoms, reduced lung function, bronchial reactivity, and asthma, the relationship of hospital morbidity for respiratory infections to a relatively low level of exposure to air pollution in children has...

Effects of fine particles on children’s hospital admissions for respiratory health in Seville, Spain

“…Thus, those concentrations of pollutant are associated with the children's hospital admissions due to bronchiolitis, pneumonia, asthma, and bronchitis and other causes. Therefore, this study is consistent with the results shown in other similar works that relate child hospital admissions to PM 2.5 (e.g., Dockery et al, 1989;Lin et al, 2005;Schwartz and Neas, 2000). It is also in line with the results shown in studies that relate this pollutant to cases of pneumonia (Ilabaca et al, 1999) and bronchitis (Barnett et al, 2005), and also with those that relate hospital emergencies due to chronic obstructive pulmonary disease and asthma (Katsouyanni, 2001).…”

“…They analyzed the emergency hospital admissions of children due to all causes, except trauma, in Madrid and found that the only primary pollutant statistically significant was the PM 2.5 concentration, and the relative risk associated with an increase of 10 μg/m 3 in PM 2.5 concentration was 1.03 for children less than 10 years old. In other countries, the impact of fine particle on children health, and specifically on children's respiratory health, has been analyzed by Dockery et al (1989), Lin et al (2005), Schwartz and Neas (2000), Ilabaca et al (1999), Barnett et al (2005), and Magas et al (2007). These latter papers led to the conclusions that first, the results provide further evidence that the rates of respiratory illnesses and symptoms are elevated among children living in cities with high particulate pollution (particularly fine particulates).…”

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

“…Possible links between air pollution, particularly that caused by atmospheric particles and SO 2 , and the number of hospital admissions have been recently established in studies from North America, [3][4][5][6][7][8][9][10][11][12] South America, [13][14][15][16] Asia, [17][18][19][20][21][22] Australia 22 and Europe. [23][24][25][26][27][28][29][30][31][32][33][34][35] However, there are still many aspects to elucidate the causal relationships between air pollution and physical condition, such as the separation of the short-term and long-term health effects of individual air pollutants and those of complex pollutant mixtures.…”

The Effects of PM_2.5 from Asian Dust Storms on Emergency Room Visits for Cardiovascular and Respiratory Diseases

“…Seniors typically have higher ER visits for CVD, which leads to a higher susceptibility to PM2.5. Other research [17] has supported this fact by showing that those under the age of 65 are less likely than their older counterparts to be hospitalized for CVDs during PM2.5 exposure. Women might be more susceptible because of hormones, but research on the interaction between sex and air pollution has not yet proved such a thing [31].…”

“…Previous environmentally epidemiological studies have shown positive correlations of particulate matter (PM) on the risk of death [4][5][6][7][8][9], hospitalizations [3,[10][11][12][13][14][15][16][17], and emergency room 2 of 4 (ER) visits [8,[18][19][20][21]. In Barcelona, Spain, a case-crossover study from 2003 to 2007 indicated that PM2.5 from car exhaust, gas combustion, hyponitrites, hydrosulfites, and road dust are correlated to CVD mortality (p<0.05); for every 10µg/m 3 increase in PM2.5, cardiovascular-related mortality increased by 2.9% (95% CI: 1.4-4.4) [9].…”