Acute effects of ambient non-methane hydrocarbons on cardiorespiratory hospitalizations: A multicity time-series study in Taiwan

Hong Qiu; Kai-Jen Chuang; Yen-Chun Fan; Ta-Pang Chang; Chyi-Huey Bai; Kin-Fai Ho

doi:10.1016/j.ecoenv.2022.113370

Acute effects of ambient non-methane hydrocarbons on cardiorespiratory hospitalizations: A multicity time-series study in Taiwan

Ecotoxicol Environ Saf. 2022 Apr 1:234:113370. doi: 10.1016/j.ecoenv.2022.113370. Epub 2022 Mar 4.

Authors

Hong Qiu¹, Kai-Jen Chuang², Yen-Chun Fan³, Ta-Pang Chang³, Chyi-Huey Bai⁴, Kin-Fai Ho⁵

Affiliations

¹ JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China; Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China.
² Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
³ School of Public Health, College of Public Health, Taipei Medical University, Taipei, Taiwan.
⁴ Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; School of Public Health, College of Public Health, Taipei Medical University, Taipei, Taiwan. Electronic address: baich@tmu.edu.tw.
⁵ JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China; Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China. Electronic address: kfho@cuhk.edu.hk.

PMID: 35255250
DOI: 10.1016/j.ecoenv.2022.113370

Abstract

Background: Few environmental epidemiological studies and no large multicity studies have evaluated the acute short-term health effects of ambient non-methane hydrocarbons (NMHC), the essential precursors of ground-level ozone and secondary organic aerosol formation.

Objective: We conducted this multicity time-series study in Taiwan to evaluate the association between airborne NMHC exposure and cardiorespiratory hospital admissions.

Methods: We collected the daily mean concentrations of NMHC, fine particulate matter (PM_2.5), ozone (O₃), weather conditions, and daily hospital admission count for cardiorespiratory diseases between 2014 and 2017 from eight major cities of Taiwan. We applied an over-dispersed generalized additive Poisson model (GAM) with adjustment for temporal trends, seasonal variations, weather conditions, and calendar effects to compute the effect estimate for each city. Then we conducted a random-effects meta-analysis to pool the eight city-specific effect estimates to obtain the overall associations of NMHC exposure on lag0 day with hospital admissions for respiratory and circulatory diseases, respectively.

Results: On average, a 0.1-ppm increase of lag0 NMHC demonstrated an overall 0.9% (95% CI: 0.4-1.3%) and 0.8% (95% CI: 0.4-1.2%) increment of hospital admissions for respiratory and circulatory diseases, respectively. Further analyses with adjustment for PM_2.5 and O₃ in the multi-pollutant model or sensitivity analyses with restricting the NMHC monitoring from the general stations only confirmed the robustness of the association between ambient NMHC exposure and cardiorespiratory hospitalizations.

Conclusion: Our findings provide robust evidence of higher cardiorespiratory hospitalizations in association with acute exposure to ambient NMHC in eight major cities of Taiwan.

Keywords: Cardiorespiratory diseases; Hospital admissions; Meta-analysis; Multicity time-series study; Non-methane hydrocarbons.