Document


Title

Landscape fire smoke enhances the association between fine particulate matter exposure and acute respiratory infection among children under 5 years of age: findings of a case-crossover study for 48 low- and middle-income countries
Document Type: Journal Article
Author(s): Jiajianghui Li; Yutong Samuel Cai; Frank J. Kelly; Martin J. Wooster; Yiqun Han; Yixuan Zheng; Tianjia Guan; Pengfei Li; Tong Zhu; Tao Xue
Publication Year: 2023

Cataloging Information

Keyword(s):
  • children
  • landscape fire
  • PM - particulate matter
  • PM2.5
  • public health
  • respiratory infections
Record Maintained By:
Record Last Modified: December 7, 2022
FRAMES Record Number: 66991

Description

Background: Fine particulate matter (PM2.5) produced by landscape fires is thought to be more toxic than that from non-fire sources. However, the effects of “fire-sourced” PM2.5 on acute respiratory infection (ARI) are unknown.

Methods: We combined Demographic and Health Survey (DHS) data from 48 countries with gridded global estimates of PM2.5 concentrations from 2003 to 2014. The proportions of fire-sourced PM2.5 were assessed by a chemical transport model using a variety of PM2.5 source data. We tested for associations between ARI and short-term exposure to fire- and “non-fire-sourced” PM2.5 using a bidirectional case-crossover analysis. The robustness and homogeneity of the associations were examined by sensitivity analyses. We also established a nonlinear exposure–response relationship between fire- and non-fire-sourced PM2.5 and ARI using a two-dimensional spline function.

Results: The study included 36,432 children under 5 years who reported ARI symptoms. Each 1 µg/m3 increment of fire-sourced PM2.5 was associated with a 3.2% (95% confidence interval [CI] 0.2, 6.2) increment in the risk of ARI. This effect was comparable to that of each 5 µg/m3 increment in PM2.5 from non-fire sources (3.1%; 95% CI 2.4, 3.7). The association between ARI and total PM2.5 concentration was significantly mediated by the proportion of fire-sourced particles. Nonlinear analysis showed that the risk of ARI was increased by both fire- and non-fire-sourced PM2.5, but especially by the former.

Conclusions: PM2.5 produced by landscape fire was more strongly associated to ARI among children under 5 years than that from non-fire sources.

Online Link(s):
Citation:
Li, Jiajianghui; Cai, Yutong Samuel; Kelly, Frank J.; Wooster, Martin J.; Han, Yiqun; Zheng, Yixuan; Guan, Tianjia; Li, Pengfei; Zhu, Tong; Xue, Tao. 2023. Landscape fire smoke enhances the association between fine particulate matter exposure and acute respiratory infection among children under 5 years of age: findings of a case-crossover study for 48 low- and middle-income countries. Environment International 171:107665.