Fires started by people account for a majority of premature deaths related to inhalation of tiny smoke particles in the United States, a new study reveals.
These blazes, which are increasing, led to 20,000 premature deaths in 2018. That was 270% more than in 2003, according to researchers at Massachusetts Institute of Technology, in Cambridge.
More than 80% of the premature deaths related to smoke particles stem from human-ignited fires, including agricultural burns and wildfires, according to the report published online Jan. 16 in the journal Environmental Research Letters.
“Fires not only threaten human lives, infrastructure and ecosystems, but they are also a major cause for concern in terms of air quality. High levels of smoke exposure can negatively impact human health, resulting in conditions such as respiratory infections, lung cancer, heart disease and even premature births," Dr. Therese Carter, lead study author, said in a journal news release.
"Our results show that a large and significant portion of harmful smoke particles result directly from human-lit fires,” she added.
Looking at the relationships between smoke particles and air quality, the study authors concluded that more than 67% of small particles called PM2.5 in U.S. air come from human-ignited fires.
For the study, the investigators used the Global Fire Emissions Database to quantify agricultural fire emissions, then classify these fires into two categories: human versus natural ignition.
The researchers simulated the concentration of smoke particles across the United States. Then they determined if these fires are human-ignited, they have the potential to be managed.
For example, state agencies can restrict the ignition of agricultural fires to periods when weather conditions would minimize health impacts, the study authors said.
Human-ignited wildfires are much harder to manage due to their sporadic and unplanned nature, according to the team.
“Now that we know that humans can play a pivotal role in reducing PM2.5 concentrations, we should be putting policies, regulations and management plans in place to reduce human-ignited fires. Efforts to minimize human-ignited fires should be focused on certain regions and ignition types in order to be more successful,” Carter said. “Identifying and acknowledging the sources of these particles is the first step in a cleaner, healthier future.”
The U.S. Environmental Protection Agency has more on PM2.5.
SOURCE: Environmental Research Letters, news release, Jan. 16, 2023