Association of residential exposure to hazardous air pollutants with risk of non-Hodgkin lymphoma and multiple myeloma.

BACKGROUND: Certain hazardous air pollutants (HAPs) are known or suspected to pose immunological or cancer risk to humans, but evidence is limited from the general population.

METHODS: We assessed associations between residential exposure to HAPs at the Census tract level and incident non-Hodgkin lymphoma (NHL) and multiple myeloma (MM) in the Nurses' Health Study (NHS, 1986-2012) and NHSII (1989-2019). We used covariate-adjusted proportional hazards models to estimate hazard ratios (HRs) of NHL, major NHL subtypes, and MM per interquartile range increase in exposure to a given HAP and pooled the cohort-specific estimates using fixed-effects meta-analyses.

RESULTS: There were 810 NHL and 158 MM cases in NHS (1,700,707 person-years), and 379 NHL and 59 MM cases in NHSII (2,820,772 person-years). Most HRs approximated unity. Meta-analyses did not show consistent evidence of associations between any HAP exposure and risk of NHL or MM.

CONCLUSIONS: Exposure to HAPs was not consistently associated with risks of NHL or MM in these nationwide prospective cohorts of women.

IMPACT: This is the first nationwide study assessing associations between residential HAP exposures and risk of lymphoid malignances in prospective cohorts and focuses on women, who have frequently been underrepresented in (primarily occupational) studies of exposure to HAPs.