Citation

Ma Y, Zang E, Liu Y, Wei J, Lu Y, Krumholz HM, Bell ML, Chen K. medRxiv 2024; ePub(ePub): ePub.

Copyright

(Copyright © 2024, The Author(s), Publisher Cold Spring Harbor Laboratory, BMJ Publishing Group, Yale University)

DOI

10.1101/2023.01.31.23285059

PMID

36778437

PMCID

PMC9915814

Abstract

Despite the growing evidence on the health effects of short-term exposure to wildfire smoke fine particles (PM(2.5)), the impacts of long-term wildfire smoke PM(2.5) exposure remain unclear. We investigated the association between long-term exposure to wildfire smoke PM(2.5) and all-cause mortality and mortality from a wide range of specific causes in all 3,108 counties in the contiguous U.S., 2007-2020. Monthly county-level mortality data were collected from the National Center for Health Statistics. Wildfire smoke PM(2.5) concentration was derived from a 10×10 km(2) resolution spatiotemporal model. Controlling for non-smoke PM(2.5), air temperature, and unmeasured spatial and temporal confounders, we found a non-linear association between 12-month moving average concentration of smoke PM(2.5) and monthly all-cause mortality rate. Relative to a month with the long-term smoke PM(2.5) exposure below 0.1 μg/m(3), all-cause mortality increased by 0.40-1.54 and 3.65 deaths per 100,000 people per month when the 12-month moving average of PM(2.5) concentration was of 0.1-5 and 5+ μg/m(3), respectively. Cardiovascular, ischemic heart disease, digestive, endocrine, diabetes, mental, suicide, and chronic kidney disease mortality were all found to be associated with long-term wildfire smoke PM(2.5) exposure. Smoke PM(2.5) contributed to approximately 30,180 all-cause deaths/year (95% CI: 21,449, 38,910) in the contiguous U.S. Higher smoke PM(2.5)-related increases in mortality rates were found for people aged 65 above and racial minority populations. Positive interaction effects with extreme heat were also observed. Our study identified the detrimental effects of long-term exposure to wildfire smoke PM(2.5) on a wide range of mortality outcomes, underscoring the need for public health actions and communication to prepare communities and individuals to mitigate smoke exposure.

Language: en

Keywords

Biological Sciences; Environmental Sciences; fine particulate matter; mortality; United States; wildfire