Long-term exposure to low-level air pollution and greenness and mortality in Northern Europe. The Life-GAP project

Shanshan Xu; Alessandro Marcon; Randi Jacobsen Bertelsen; Bryndis Benediktsdottir; Jørgen Brandt; Kristine Engemann; Lise Marie Frohn; Camilla Geels; Thorarinn Gislason; Joachim Heinrich; Mathias Holm; Christer Janson; Iana Markevych; Lars Modig; Hans Orru; Vivi Schlünssen; Torben Sigsgaard; Ane Johannessen

doi:10.1016/j.envint.2023.108257

Long-term exposure to low-level air pollution and greenness and mortality in Northern Europe. The Life-GAP project

Environ Int. 2023 Nov:181:108257. doi: 10.1016/j.envint.2023.108257. Epub 2023 Oct 11.

Authors

Shanshan Xu¹, Alessandro Marcon², Randi Jacobsen Bertelsen³, Bryndis Benediktsdottir⁴, Jørgen Brandt⁵, Kristine Engemann⁶, Lise Marie Frohn⁵, Camilla Geels⁵, Thorarinn Gislason⁴, Joachim Heinrich⁷, Mathias Holm⁸, Christer Janson⁹, Iana Markevych¹⁰, Lars Modig¹¹, Hans Orru¹², Vivi Schlünssen¹³, Torben Sigsgaard¹³, Ane Johannessen¹⁴

Affiliations

¹ Centre for International Health, Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway. Electronic address: shanshan.xu@uib.no.
² Unit of Epidemiology and Medical Statistics, Department of Diagnostics and Public Health, University of Verona, Verona, Italy.
³ Department of Clinical Science, University of Bergen, Bergen, Norway.
⁴ Department of Respiratory Medicine and Sleep, Landspitali - the National University Hospital of Iceland, Reykjavik, Iceland.
⁵ Department of Environmental Science, Aarhus University, Roskilde, Denmark.
⁶ Section for Ecoinformatics & Biodiversity, Department of Bioscience, Aarhus University, Aarhus C, Denmark.
⁷ Institute and Clinic for Occupational, Social and Environmental Medicine, University Hospital, Ludwig Maximilian University of Munich, Munich, Germany; Allergy and Lung Health Unit, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia.
⁸ Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
⁹ Department of Medical Sciences: Respiratory, Allergy and Sleep Research, Uppsala University, Uppsala, Sweden.
¹⁰ Institute of Psychology, Jagiellonian University, Krakow, Poland.
¹¹ Department of Public Health and Clinical Medicine, Section of Sustainable Health, Umeå University, Sweden.
¹² Department of Public Health, Institute of Family Medicine and Public Health, Faculty of Medicine, University of Tartu, Tartu, Estonia.
¹³ Department of Public Health, Research Unit for Environment Occupation and Health, Danish Ramazzini Center, Aarhus University, Aarhus, Denmark.
¹⁴ Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway.

PMID: 37857189
DOI: 10.1016/j.envint.2023.108257

Abstract

Background: Air pollution has been linked to mortality, but there are few studies examining the association with different exposure time windows spanning across several decades. The evidence for the effects of green space and mortality is contradictory.

Objective: We investigated all-cause mortality in relation to exposure to particulate matter (PM_2.5 and PM₁₀), black carbon (BC), nitrogen dioxide (NO₂), ozone (O₃) and greenness (normalized difference vegetation index - NDVI) across different exposure time windows.

Methods: The exposure assessment was based on a combination of the Danish Eulerian Hemispheric Model and the Urban Background Model for the years 1990, 2000 and 2010. The analysis included a complete case dataset with 9,135 participants from the third Respiratory Health in Northern Europe study (RHINE III), aged 40-65 years in 2010, with mortality follow-up to 2021. We performed Cox proportional hazard models, adjusting for potential confounders.

Results: Altogether, 327 (3.6 %) persons died in the period 2010-2021. Increased exposures in 1990 of PM_2.5, PM₁₀, BC and NO₂ were associated with increased all-cause mortality hazard ratios of 1.40 (95 % CI1.04-1.87 per 5 μg/m³), 1.33 (95 % CI: 1.02-1.74 per 10 μg/m³), 1.16 (95 % CI: 0.98-1.38 per 0.4 μg/m³) and 1.17 (95 % CI: 0.92-1.50 per 10 μg/m³), respectively. No statistically significant associations were observed between air pollution and mortality in other time windows. O₃ showed an inverse association with mortality, while no association was observed between greenness and mortality. Adjusting for NDVI increased the hazard ratios for PM_2.5, PM₁₀, BC and NO₂ exposures in 1990. We did not find significant interactions between greenness and air pollution metrics.

Conclusion: Long term exposure to even low levels of air pollution is associated with mortality. Opening up for a long latency period, our findings indicate that air pollution exposures over time may be even more harmful than anticipated.

Keywords: Green space; Long-term effect; Nitrogen dioxide; Ozone; Particulate matter; Premature mortality.

MeSH terms

Air Pollutants* / adverse effects
Air Pollution*
Environmental Exposure / adverse effects
Europe
Humans
Nitrogen Dioxide
Ozone*
Particulate Matter / adverse effects
Soot

Substances

Nitrogen Dioxide
Ozone
Particulate Matter
Soot
Air Pollutants