Effect modification by temperature on the association between O3 and emergency ambulance dispatches in Japan: A multi-city study

Arthit Phosri; Kayo Ueda; Xerxes Seposo; Akiko Honda; Hirohisa Takano

doi:10.1016/j.scitotenv.2022.160725

Effect modification by temperature on the association between O₃ and emergency ambulance dispatches in Japan: A multi-city study

Sci Total Environ. 2023 Feb 25:861:160725. doi: 10.1016/j.scitotenv.2022.160725. Epub 2022 Dec 6.

Authors

Arthit Phosri¹, Kayo Ueda², Xerxes Seposo³, Akiko Honda⁴, Hirohisa Takano⁴

Affiliations

¹ Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Japan; Department of Environmental Health Sciences, Faculty of Public Health, Mahidol University, Bangkok, Thailand; Center of Excellence on Environmental Health and Toxicology (EHT), OPS, Ministry of Higher Education, Science, Research and Innovation, Bangkok, Thailand. Electronic address: arthit.pho@mahidol.ac.th.
² Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Japan; Department of Hygiene, Social Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan; Graduate School of Global Environmental Sciences, Kyoto University, Kyoto, Japan.
³ Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Japan; Department of Hygiene, Social Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
⁴ Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Japan; Graduate School of Global Environmental Sciences, Kyoto University, Kyoto, Japan.

PMID: 36493818
DOI: 10.1016/j.scitotenv.2022.160725

Abstract

Numerous epidemiological studies have reported that ozone (O₃) and temperature are independently associated with health outcomes, but modification of the effects of O₃ on health outcomes by temperature, and vice versa, has not been fully described. This study aimed to investigate effect modification by temperature on the association between O₃ and emergency ambulance dispatches (EADs) in Japan. Data on daily air pollutants, ambient temperature, and EADs were obtained from eight Japanese cities from 2007 to 2015. A distributed lag non-linear model combined with Poisson regression was performed with temperature as a confounding factor and effect modifier to estimate the effects of O₃ on EADs at low (<25th percentile), moderate (25th-75th percentile), and high (>75th percentile) temperature for each city. The estimates obtained from each city were pooled by random-effects meta-analysis. When temperature was entered as a confounder, the estimated effects of O₃ on EADs for all acute, cardiovascular, and respiratory illnesses were largest at lag 0 (current-day lag). Therefore, this lag was used to further estimate the effects of O₃ on EADs in each temperature category. The estimated effects of O₃ on EADs for all acute, cardiovascular, and respiratory illnesses in all eight Japanese cities increased with increasing temperature. Specifically, a 10 ppb increase in O₃ was associated with 0.80 % (95 % CI: 0.25 to 1.35), 0.19 % (95 % CI: -0.85 to 1.25), and 1.14 % (95 % CI: -0.01 to 2.31) increases in the risk of EADs for all acute, cardiovascular, and respiratory illnesses, respectively, when city-specific daily temperature exceeded the 75th percentile. Our findings suggest that the association between O₃ and EADs for all acute, cardiovascular, and respiratory illnesses is the highest during high temperature. Finding of this study can be used to develop potential mitigation measures against O₃ exposure in high temperature environment to reduce its associated adverse health effects.

Keywords: Effect modification; Emergency ambulance dispatch; High temperature; Ozone.

Publication types

Meta-Analysis

MeSH terms

Air Pollutants* / analysis
Air Pollution* / analysis
Ambulances
Cities
Japan / epidemiology
Particulate Matter / analysis
Temperature

Substances

Air Pollutants
Particulate Matter