BACKGROUND: Few population-based epidemiological studies of adults have examined the relationship between air pollution and
leukaemias.
METHODS: Using Danish National Cancer Registry data and Danish DEHM-UBM-AirGIS system-modelled air pollution exposures, we
examined whether particulate matter (PM2.5), black carbon (BC), nitrogen dioxide (NO2) and ozone (O3) averaged over 1, 5 or 10
years were associated with adult leukaemia in general or by subtype. In all, 14,986 adult cases diagnosed 1989–2014 and 51,624
age, sex and time-matched controls were included. Separate conditional logistic regression models, adjusted for sociodemographic
factors, assessed exposure to each pollutant with leukaemias.
RESULTS: Fully adjusted models showed a higher risk of leukaemia with higher 1-, 5- and 10-year-average exposures to PM2.5 prior
to diagnosis (e.g. OR per 10 μg/m3 for 10-year average: 1.17, 95% CI: 1.03, 1.32), and a positive relationship with 1-year average BC.
Results were driven by participants 70 years and older (OR per 10 μg/m3 for 10-year average: 1.35, 95% CI: 1.15–1.58). Null findings
for younger participants. Higher 1-year average PM2.5 exposures were associated with higher risks for acute myeloid and chronic
lymphoblastic leukaemia.
CONCLUSION: Among older adults, higher risk for leukaemia was associated with higher residential PM2.5 concentrations averaged
over 1, 5 and 10 years prior to diagnosis.
