Uncertainty in health impact assessments of smoke from a wildfire event

Manuscript abstract: Wildfires cause elevated air pollution that can be
detrimental to human health. However, health impact assessments associated
with emissions from wildfire events are subject to uncertainty arising
from different sources. Here, we quantify and compare major uncertainties
in mortality and morbidity outcomes of exposure to fine particulate matter
(PM2.5) pollution estimated for a series of wildfires in the Southeastern
U.S. We present an approach to compare uncertainty in estimated health
impacts specifically due to two driving factors, wildfire-related smoke
PM2.5 fields and variability in concentration-response parameters from
epidemiologic studies of ambient and smoke PM2.5. This analysis focused on
the 2016 Southeastern United States wildfires suggests that emissions from
these wildfires had public health consequences in North Carolina. Using
multiple methods based on publicly available monitor data and atmospheric
models to represent wildfire-attributable PM2.5, we estimate impacts on
several health outcomes and quantify associated uncertainty. Multiple
concentration-response parameters derived from studies of ambient and
wildfire-specific PM2.5 are used to assess health-related uncertainty.
Results show large variability and uncertainty in wildfire impact
estimates, with comparable uncertainties due to the smoke pollution fields
and health response parameters for some outcomes, but substantially larger
health-related uncertainty for several outcomes. Consideration of these
uncertainties can support efforts to improve estimates of wildfire impacts
and inform fire-related decision-making.