Early-life exposure to PM2.5 constituents and childhood asthma and wheezing: Findings from China, Children, Homes, Health study

Yuanyuan Zhang; Zhouxin Yin; Peixuan Zhou; Liansheng Zhang; Zhuohui Zhao; Dan Norbäck; Xin Zhang; Chan Lu; Wei Yu; Tingting Wang; Xiaohong Zheng; Ling Zhang; Yunquan Zhang

doi:10.1016/j.envint.2022.107297

Early-life exposure to PM_2.5 constituents and childhood asthma and wheezing: Findings from China, Children, Homes, Health study

Environ Int. 2022 Jul:165:107297. doi: 10.1016/j.envint.2022.107297. Epub 2022 May 15.

Authors

Yuanyuan Zhang¹, Zhouxin Yin¹, Peixuan Zhou¹, Liansheng Zhang¹, Zhuohui Zhao², Dan Norbäck³, Xin Zhang⁴, Chan Lu⁵, Wei Yu⁶, Tingting Wang⁷, Xiaohong Zheng⁸, Ling Zhang⁹, Yunquan Zhang¹⁰

Affiliations

¹ School of Public Health, Wuhan University of Science and Technology, Wuhan, China.
² School of Public Health, Fudan University, Shanghai, China.
³ Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
⁴ Research Centre for Environmental Science and Engineering, Shanxi University, Taiyuan, China.
⁵ Xiangya School of Public Health, Central South University, Changsha, China.
⁶ School of Civil Engineering, Chongqing University, Chongqing, China.
⁷ Shanghai University of Medicine and Health Sciences, Shanghai, China.
⁸ School of Energy and Environment, Southeast University, Nanjing, China.
⁹ School of Public Health, Wuhan University of Science and Technology, Wuhan, China; Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan 430065, China. Electronic address: zhangling@wust.edu.cn.
¹⁰ School of Public Health, Wuhan University of Science and Technology, Wuhan, China; Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan 430065, China. Electronic address: YunquanZhang@wust.edu.cn.

PMID: 35709580
DOI: 10.1016/j.envint.2022.107297

Abstract

Background: Emerging evidence suggests that early-life (in-utero and first-year since birth) exposure to ambient PM_2.5 is a risk factor for asthma onset and exacerbation among children, while the hazards caused by PM_2.5 compositions remain largely unknown.

Objective: To examine potential associations of early-life exposures to PM_2.5 mass and its major chemical constituents with childhood asthma and wheezing.

Methods: By conducting the Phase II of the China, Children, Homes, Health study, we investigated 30,325 preschool children aged 3-6 years during 2019-2020 in mainland China. Early-life exposure to PM_2.5 mass and its constituents (i.e., black carbon [BC], organic matter [OM], nitrate, ammonium, sulfate) were calculated based on monthly estimates at a 1 km × 1 km resolution from satellite-based models. We adopted a novel quantile-based g-computation approach to assess the effect of a mixture of PM_2.5 constituents on childhood asthma/wheezing.

Results: The average PM_2.5 concentrations during in-utero and the first year since birth were 64.7 ± 10.6 and 61.8 ± 10.5 µg/m³, respectively. Early-life exposures to a mixture of major PM_2.5 constituents were significantly associated with increased risks of asthma and wheezing, while no evident compositions-wheezing associations were found in the first year. Each quintile increases in all five PM_2.5 components exposures in utero was accordingly associated with an odds ratio of 1.18 [95% confidence interval: 1.07-1.29] for asthma and 1.08 [1.01-1.16] for wheezing. BC, OM and SO₄^2- contributed more to risks of asthma and wheezing than the other PM_2.5 constituents during early life, wherein the effects of BC were only observed during pregnancy. Sex subgroup analyses suggested stronger associations among girls of first-year exposures to PM_2.5 components with childhood asthma.

Conclusion: Early-life exposures to ambient PM_2.5, particularly compositions of BC, OM and SO₄^2-, are associated with an increased risk of childhood asthma.

Keywords: Childhood asthma; Early life; PM(2.5) constituents; Quantile-based g-computation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Air Pollutants* / analysis
Air Pollution* / analysis
Asthma* / chemically induced
Asthma* / etiology
Child, Preschool
China / epidemiology
Environmental Exposure / adverse effects
Environmental Exposure / analysis
Female
Humans
Particulate Matter / analysis
Pregnancy
Respiratory Sounds / etiology

Substances

Air Pollutants
Particulate Matter