Long-term exposure to fine particulate matter and site-specific cancer mortality: A difference-in-differences analysis in Jiangsu province, China

Zhaoyu Fan; Yingxin Li; Jing Wei; Gongbo Chen; Rui Wang; Ruijun Xu; Tingting Liu; Ziquan Lv; Suli Huang; Hong Sun; Yuewei Liu

doi:10.1016/j.envres.2023.115405

Long-term exposure to fine particulate matter and site-specific cancer mortality: A difference-in-differences analysis in Jiangsu province, China

Environ Res. 2023 Apr 1:222:115405. doi: 10.1016/j.envres.2023.115405. Epub 2023 Feb 2.

Authors

Zhaoyu Fan¹, Yingxin Li¹, Jing Wei², Gongbo Chen³, Rui Wang⁴, Ruijun Xu¹, Tingting Liu¹, Ziquan Lv⁵, Suli Huang⁶, Hong Sun⁷, Yuewei Liu⁸

Affiliations

¹ Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China.
² Department of Atmospheric and Oceanic Science, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, 20740, USA.
³ Climate, Air Quality Research Unit, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, 3004, Australia.
⁴ Luohu District Chronic Disease Hospital, Shenzhen, Guangdong, 518020, China.
⁵ Central Laboratory of Shenzhen Center for Disease Control and Prevention, Shenzhen, Guangdong, 518055, China.
⁶ Department of Environment and Health, Shenzhen Center for Disease Control and Prevention, Shenzhen, Guangdong, 518055, China.
⁷ Department of Environment and Health, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, 210009, China. Electronic address: hongsun@jscdc.cn.
⁸ Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China. Electronic address: liuyuewei@mail.sysu.edu.cn.

PMID: 36736553
DOI: 10.1016/j.envres.2023.115405

Abstract

Background: Accumulating studies have reported that chronic exposure to ambient fine particulate matter (PM_2.5) can lead to adverse effects on lung cancer mortality; however, such chronic effects are less clear for mortality from other site-specific cancers.

Objective: To explore the causal effect of long-term PM_2.5 exposure on mortality from all-site and a variety of site-specific cancers in Jiangsu province, China during 2015-2020 using a difference-in-differences analysis.

Methods: For each of 53 county-based spatial units in Jiangsu province, we calculated annual death counts for all-site cancer and 23 site-specific cancers. Using a validated high-resolution PM_2.5 grid dataset, long-term PM_2.5 exposure of a spatial unit within a given year was evaluated as the average of population-weighted annual concentrations during recent 10 years. Conditional Poisson regression models were employed to evaluate exposure-response associations adjusting for spatial and temporal variables, seasonal temperatures, relative humidity, and gross domestic product (GDP).

Results: During the study period, we identified 947,337 adult cancer deaths in Jiangsu province. Each 1 μg/m³ increment in PM_2.5 exposure was significantly associated with a 2.7% increase in the risk of all-site cancer mortality. PM_2.5-mortality associations were also observed in cancer of lip, oral cavity and pharynx, stomach, colorectum, pancreas, lung, bone and joints, ovary, prostate, and lymphoma (all adjusted P < 0.05), with the relative risks ranging from 1.028 (95% confidence interval [CI]: 1.011, 1.046) for stomach cancer to 1.201 (95% CI: 1.120, 1.308) for bone and joints cancers. Exposure-response curves showed that these associations were close to linearity, though most of them had increasing slopes at high exposure levels. Overall, women and subjects in low GDP regions were more vulnerable to PM_2.5 exposures.

Conclusions: Long-term exposure to ambient PM_2.5 contributes to a higher risk of mortality from multiple site-specific cancers.

Keywords: Cancer; Difference-in-differences; Fine particulate matter; Long-term exposure; Mortality.

MeSH terms

Adult
Air Pollutants* / toxicity
Air Pollution* / analysis
China
Environmental Exposure / analysis
Female
Humans
Lung Neoplasms* / chemically induced
Male
Particulate Matter / analysis
Risk

Substances

Particulate Matter
Air Pollutants