Estimated Impacts of Prescribed Fires on Air Quality and Premature Deaths in Georgia and Surrounding Areas in the US, 2015–2020

Abstract

High Resolution Image Download MS PowerPoint Slide Smoke from wildfires poses a substantial threat to health in communities near and far. To mitigate the extent and potential damage of wildfires, prescribed burning techniques are commonly employed as land management tools; however, they introduce their own smoke-related risks. This study investigates the impact of prescribed fires on daily average PM 2.5 and maximum daily 8-h averaged O 3 (MDA8-O 3 ) concentrations and estimates premature deaths associated with short-term exposure to prescribed fire PM 2.5 and MDA8-O 3 in Georgia and surrounding areas of the Southeastern US from 2015 to 2020. Our findings indicate that over the study domain, prescribed fire contributes to average daily PM 2.5 by 0.94 ± 1.45 μg/m 3 (mean ± standard deviation), accounting for 14.0% of year-round ambient PM 2.5 . Higher average daily contributions were predicted during the extensive burning season (January–April): 1.43 ± 1.97 μg/m 3 (20.0% of ambient PM 2.5 ). Additionally, prescribed burning is also responsible for an annual average increase of 0.36 ± 0.61 ppb in MDA8-O 3 (approximately 0.8% of ambient MDA8-O 3 ) and 1.3% (0.62 ± 0.88 ppb) during the extensive burning season. We estimate that short-term exposure to prescribed fire PM 2.5 and MDA8-O 3 could have caused 2665 (95% confidence interval (CI): 2249–3080) and 233 (95% CI: 148–317) excess deaths, respectively. These results suggest that smoke from prescribed burns increases the mortality. However, refraining from such burns may escalate the risk of wildfires; therefore, the trade-offs between the health impacts of wildfires and prescribed fires, including morbidity, need to be taken into consideration in future studies.