Background: An association between long-term exposure to fine particulate matter (PM2.5) and lung cancer has been established in previous studies. PM2.5 is a complex mixture of chemical components from various sources and little is known about whether certain components contribute specifically to the associated lung cancer risk. The present study builds on recent findings from the “Effects of Low-level Air Pollution: A Study in Europe” (ELAPSE) collaboration and addresses the potential association between specific elemental components of PM2.5 and lung cancer incidence.
Methods: We pooled seven cohorts from across Europe and assigned exposure estimates for eight components of PM2.5 representing non-tail pipe emissions (copper (Cu), iron (Fe), and zinc (Zn)), long-range transport (sulfur (S)), oil burning/industry emissions (nickel (Ni), vanadium (V)), crustal material (silicon (Si)), and biomass burning (potassium (K)) to cohort participants’ baseline residential address based on 100 m by 100 m grids from newly developed hybrid models combining air pollution monitoring, land use data, satellite observations, and dispersion model estimates. We applied stratified Cox proportional hazards models, adjusting for potential confounders (age, sex, calendar year, marital status, smoking, body mass index, employment status, and neighborhood-level socio-economic status). Results: The pooled study population comprised 306,550 individuals with 3,916 incident lung cancer events during 5,541,672 person-years of follow-up. We observed a positive association between exposure to all eight components and lung cancer incidence, with adjusted HRs of 1.10 (95% CI 1.05, 1.16) per 50 ng/m3 PM2.5 K, 1.09 (95% CI 1.02, 1.15) per 1 ng/m3 PM2.5 Ni, 1.22 (95% CI 1.11, 1.35) per 200 ng/m3 PM2.5 S, and 1.07 (95% CI 1.02, 1.12) per 200 ng/m3 PM2.5 V. Effect estimates were largely unaffected by adjustment for nitrogen dioxide (NO2). After adjustment for PM2.5 mass, effect estimates of K, Ni, S, and V were slightly attenuated, whereas effect estimates of Cu, Si, Fe, and Zn became null or negative.
Conclusions: Our results point towards an increased risk of lung cancer in connection with sources of combustion particles from oil and biomass burning and secondary inorganic aerosols rather than non-exhaust traffic emissions. Specific limit values or guidelines targeting these specific PM2.5 components may prove helpful in future lung cancer prevention strategies.
Authors: Ulla Arthur Hvidtfeldt, Jie Chen, Zorana Jovanovic Andersen, Richard Atkinson, Mariska Bauwelinck, Tom Bellander, Jørgen Brandt, Bert Brunekreef, Giulia Cesaroni, Hans Concin, Daniela Fecht, Francesco Forastiere, Carla H van Gils, John Gulliver, Ole Hertel, Gerard Hoek, Barbara Hoffmann, Kees de Hoogh, Nicole Janssen, Jeanette Therming Jørgensen, Klea Katsouyanni, Karl-Heinz Jöckel, Matthias Ketzel, Jochem O Klompmaker, Alois Lang, Karin Leander, Shuo Liu, Petter L S Ljungman, Patrik K E Magnusson, Amar Jayant Mehta, Gabriele Nagel, Bente Oftedal, Göran Pershagen, Raphael Simon Peter, Annette Peters, Matteo Renzi, Debora Rizzuto, Sophia Rodopoulou, Evangelia Samoli, Per Everhard Schwarze, Gianluca Severi, Torben Sigsgaard, Massimo Stafoggia, Maciej Strak, Danielle Vienneau, Gudrun Weinmayr, Kathrin Wolf, Ole Raaschou-Nielsen
; Full Source: Environmental research 2020 Dec 2;110568. doi: 10.1016/j.envres.2020.110568.