In-Home Particle Concentrations and Childhood Asthma Morbidity

Abstract

BackgroundAlthough outdoor particulate matter (PM) has been linked to mortality and asthma morbidity, the impact of indoor PM on asthma has not been well established.ObjectiveThis study was designed to investigate the effect of in-home PM on asthma morbidity.MethodsFor a cohort of 150 asthmatic children (2–6 years of age) from Baltimore, Maryland, a technician deployed environmental monitoring equipment in the children’s bedrooms for 3-day intervals at baseline and at 3 and 6 months. Caregivers completed questionnaires and daily diaries during air sampling. Longitudinal data analyses included regression models with generalized estimating equations.ResultsChildren were primarily African Americans (91%) from lower socioeconomic backgrounds and spent most of their time in the home. Mean (± SD) indoor PM2.5–10 (PM with aerodynamic diameter 2.5–10 μm) and PM2.5 (aerodynamic diameter < 2.5 μm) concentrations were 17.4 ± 21.0 and 40.3 ± 35.4 μg/m3. In adjusted models, 10-μg/m3 increases in indoor PM2.5–10 and PM2.5 were associated with increased incidences of asthma symptoms: 6% [95% confidence interval (CI), 1 to 12%] and 3% (95% CI, –1 to 7%), respectively; symptoms causing children to slow down: 8% (95% CI, 2 to 14%) and 4% (95% CI, 0 to 9%), respectively; nocturnal symptoms: 8% (95% CI, 1 to 14%) and 6% (95% CI, 1 to 10%), respectively; wheezing that limited speech: 11% (95% CI, 3 to 19%) and 7% (95% CI, 0 to 14%), respectively; and use of rescue medication: 6% (95% CI, 1 to 10%) and 4% (95% CI, 1 to 8%), respectively. Increases of 10 μg/m3 in indoor and ambient PM2.5 were associated with 7% (95% CI, 2 to 11%) and 26% (95% CI, 1 to 52%) increases in exercise-related symptoms, respectively.ConclusionsAmong preschool asthmatic children in Baltimore, increases in in-home PM2.5–10 and PM2.5 were associated with respiratory symptoms and rescue medication use. Increases in in-home and ambient PM2.5 were associated with exercise-related symptoms. Although reducing PM outdoors may decrease asthma morbidity, reducing PM indoors, especially in homes of inner-city children, may lead to improved asthma health.

Tumor Necrosis Factor-Alpha as Biomarkers of Exposure to Indoor Pollutants Among Primary School Children in Klang Valley

“…Other studies also correspond with the current study reported that school children in urban density communities had a significant higher prevalence of respiratory symptoms compared to those living in the rural community of low traffic exposures (Skrzypek et al, 2013;Middleton et al, 2010;Siddique et al, 2011;McCormack et al, 2009). In a cross-sectional study done in 108 schools in France among 9 to 11 years old children, the risk of asthma was significantly higher in neighborhood of schools with higher concentration of urban pollutants including PM 10 , SO 2 and NO 2 (Pénard-Morand et al, 2010).…”

Respiratory health and indoor air pollutants based on quantitative exposure assessments

“…In this population, indoor particulate matter concentration has been related to a decrease in lung function, in particular among children with asthma [117][118][119][120] and, to a lesser extent, to an increased risk of asthmatic and bronchitis-like symptoms [121,122]. In a cohort of 150 asthmatic children, PM2.5 and PM2.5-10 concentrations, assessed three times every 3 months, were positively associated with the incidence rate of several respiratory symptoms, including cough, asthma symptoms and wheezing [121]. A pilot study on IAQ in a sample of schools in five European countries found that nasal patency was significantly lower in schoolchildren exposed to PM10 concentrations .50 mg?m -3 than in those exposed to concentrations ,50 mg?m -3 [34].…”

Síntomas respiratorios asociados a la exposición a contaminación del aire en cinco localidades de Bogotá, D.C., 2008-2011. Una cohorte dinámica

“…Asimismo, se observó una mayor contaminación intramuros que extramuros, lo cual se relacionó con la cercanía a fuentes de emisión de material en partículas como las vías de alto flujo vehicular, hallazgo similar al del presente estudio (23).…”

“…Aunque este estudio se proponía evaluar la contaminación extramuros con material en partículas, en varios estudios se ha afirmado que la contaminación intramuros puede ser incluso mayor que la extramuros (23). Dicho efecto se observó también en otro estudio llevado a cabo en un jardín infantil de la localidad de Puente Aranda en Bogotá, en el cual, aunque los niveles encontrados no fueron mayores en el interior que en el exterior, sí fueron similares (intramuros: 86 µg/m 3 ; extramuros: 91 µg/m 3 ) (17).…”