Independent Research: The Impact of Wildfires on Public Health

Abstract

Wildfires across the United States and other countries are responsible for extensive damage to property, infrastructure, and biomass. However, in recent decades, the frequency, intensity, and devastation caused by wildfires have increased to alarming levels – one study found that from 1984 to 2011, the rate of large fires across all ecoregions in the U.S. increased by about seven large fires per year (Dennison et al., 2014). Wildfires are no longer just local disasters; they have become global crises with severe consequences for public health and environmental stability.

Wildfire smoke (WFS) contributes significantly to the deterioration of air quality, particularly in wildland-urban areas. It contains toxic gasses and particulate matter (PM) in a variety of sizes and chemical compositions (Rizzo et al., 2024). These features of WFS have severe impacts on individuals’ health, including inflammation, DNA damage, and stress disorders. Specific modifications, such as DNA damage and epigenetic modifications, if occurring in the germline, may be propagated to future generations. It is crucial to examine the effects of wildfires on public health to identify areas where mitigation efforts can improve both wildfire management and public health outcomes.

This article will explore how wildfires cause damage and relate to public health issues while also suggesting ways to improve the situation of those affected and at risk of suffering from wildfires.

Wildfires, Pollution, and Impacts on Public Health

Often, wildfires have extensive detrimental effects on the health of those exposed, with direct impacts such as burns, injuries related to evacuation protocols, and fatalities. However, the broader health consequences stem from the pollution generated by wildfires, which introduce toxic chemicals and fine particulate matter into the air. A particularly concerning form of pollution from wildfires is fine particulate matter, known as PM2.5, which can linger in the atmosphere long after a fire has been extinguished. PM2.5 has been linked to chronic diseases, reduced life expectancy, and, in severe cases, premature death. According to Liu et al. (2016), PM2.5 concentrations are particularly high in the Western U.S. following wildfires, worsening respiratory ailments, cardiovascular issues, and other acute conditions. These risks are only further amplified during smoke waves – periods of prolonged and intense wildfire smoke exposure – which contribute to widespread air pollution and heightened health hazards. Additionally, certain populations face disproportionate exposure, with research indicating that “[the] elderly, children, people living in poverty, and non-white individuals will be exposed to smoke waves” (Liu et al., 2016), increasing their susceptibility to long-term health complications.

The presence of fine particulate matter in wildfire smoke further magnifies existing health disparities, as it disproportionately affects vulnerable populations and worsens pre-existing conditions. Studies have demonstrated that exposure to wildfire-related air pollution is strongly correlated with increased emergency room visits, hospital admissions, and elevated mortality rates (Heft-Neal et al., 2023). Moreover, prolonged exposure to wildfire smoke is also associated with heightened risks of developing respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD), as well as adverse neurological and cardiovascular effects. Beyond physical health concerns, the psychological toll of wildfires – driven by displacement, uncertainty, and prolonged exposure to hazardous air conditions – can exacerbate mental health struggles, leading to increased rates of anxiety, depression, and post-traumatic stress disorder (PTSD). Given the severe and far-reaching consequences of wildfire pollution, public health initiatives must prioritize reducing exposure through improved air quality monitoring, emergency response planning, and protective measures such as filtration systems and early warning systems. By addressing these issues proactively, society can help mitigate the health disparities exacerbated by wildfire-related air pollution, thereby reducing both the immediate and long-term toll of these environmental disasters.

Climate Change

Climate change is deeply connected to wildfires, as rising global temperatures create drier, more fire-prone landscapes. The carbon emissions from wildfires further accelerate global warming, essentially fueling a damaging cycle. Additionally, climate change contributes to the drying of organic matter in forests. Organic matter is flammable and therefore helps spread wildfires, thus having doubled the frequency of major wildfires between 1984 and 2015 in the western U.S. (Dennison et al., 2014). Higher temperatures dry out vegetation, extend fire seasons, and worsen drought conditions, which have left forests and grasslands in an increasingly flammable state, with regions like California, Australia, and the Amazon experiencing substantial, unprecedented fires. Shifting precipitation patterns further intensify the problem, as periods of significant rainfall enhance vegetation growth that later dries out, serving as fuel for future fires (Dennison et al., 2014). Another result of climate change is the increased occurrence of dry lightning strikes, which are responsible for a third of the forest fires every summer. These strikes have been estimated to increase by about 12% for each degree increase in temperature (Romps et al., 2014).

Beyond immediate destruction, wildfires contribute significantly to climate change by releasing massive amounts of carbon dioxide, methane, and other greenhouse gases into the atmosphere. The consequences of these fires extend globally, with smoke traveling thousands of miles and degrading air quality in distant regions. The 2023 Canadian wildfires, for example, created hazardous air conditions across the eastern United States, exposing millions to PM2.5 and increasing the risk of respiratory and cardiovascular diseases. These wildfires spewed air pollution that reached as far as China and Europe, displacing thousands of people from their homes. The amount of tree cover lost in these fires also produced roughly 3 billion tons of carbon dioxide, which is nearly four times the carbon emissions of the global aviation sector in 2022 (MacCarthy et al., 2024). Such events further highlight the necessity of measuring the worldwide effects of wildfires on ecosystems and greenhouse gas emissions, especially concerning the feedback loops linked to wildfires and climate change.

Public Policy

In response to the extensive and severe effects of wildfires, public policy must prioritize proactive prevention, land management, and community resilience. U.S. agencies like the Forest Service spend billions on suppression, yet underfunded prevention measures have allowed dangerous fuel buildup. For example, efforts to strengthen building codes and land-use regulations are crucial but remain inconsistent, and older homes lack fire-resistant upgrades (Sommer, 2020). Incentive-based policies, such as tax breaks for fire-resistant modifications, could improve preparedness, while expanded air quality monitoring and early warning systems are also essential, especially in vulnerable communities where wildfire smoke exacerbates respiratory and cardiovascular health issues (Lei et al., 2024). Policies should also equip emergency shelters and public buildings with clean air filtration to protect at-risk populations.

Wildfires cause not only physical destruction but also significant mental health impacts, which are often overlooked by policymakers. Research conducted by Charlson et al. (2021) in North America highlighted stress, fear, and long-term emotional distress from displacement and uncertainty. In Canada’s Northwest Territories, the 2014 wildfire season caused lasting mental health effects due to prolonged evacuations and economic disruptions. A study on Arizona’s Wallow Fire found that financial losses and solastalgia – distress from environmental change – led to heightened psychological distress, while strong family support reduced negative effects (Charlson et al., 2021). Despite frequent wildfires, countries like Australia lack research on wildfire-related mental health, exposing a policy gap. Addressing these challenges requires integrating mental health care into disaster response, strengthening community support systems, and improving long-term resilience strategies. Without comprehensive public policies that address both environmental and human impacts, wildfires will continue to devastate ecosystems and communities.

Synopsis and Future Directions

Wildfires have a direct impact on the health of individuals living in at-risk areas. These impacts particularly affect vulnerable populations, including the elderly and children. Pollution is a clear marker of adverse health effects faced by those enduring these natural disasters. Public health initiatives, such as mass communication efforts — including campaigns, public service announcements (PSAs), and social media awareness/outreach — could be used to ensure that people take proper precautions in reducing their exposure to pollutants produced by wildfires, such as PM2.5. Furthermore, funding efforts that provide proper equipment for managing wildfires, addressing pollution, and improving public health will likely reduce the amount of pollution experienced by communities in affected areas.  

Additionally, funding from governments and organizations for wildfire prevention, mitigation, emergency response, and recovery would likely enhance efforts to address both direct impacts, such as physical burns, and indirect effects, such as preserving agricultural land. As climate change progresses, it is crucial to recognize that the incidence of wildfires may correspondingly increase as well (Jones et al., 2020). Thus, funding efforts aimed at mitigating climate change are essential in safeguarding public health against the detrimental effects of wildfires.

Conclusion

Ultimately, wildfires pose a significant and escalating threat to public health, environmental stability, and global climate systems. Beyond their direct destructive capacity, wildfire smoke releases toxic pollutants that can contribute to severe respiratory, cardiovascular, and neurological issues, disproportionately affecting vulnerable populations. The psychological toll is also profound, as displacement, economic loss, and prolonged exposure to hazardous air conditions increase rates of anxiety, depression, and post-traumatic stress disorder (Charlson et al. 2021). Climate change has intensified the frequency and severity of wildfires, creating a destructive cycle that accelerates global warming and makes fire seasons longer and more dangerous.

Addressing this crisis requires comprehensive public health strategies, stronger land management policies, and increased funding for wildfire prevention and mitigation efforts. Achieving these goals will require, above all else, exceptional teamwork and collaboration among all societal members – from government leaders to individual citizens — working together to address these overarching issues. Expanding research into the long-term health effects of wildfire smoke, including its genetic and epigenetic consequences, is essential to fully understanding its impact. Future policies must integrate climate change mitigation, improved emergency preparedness, and mental health support to bolster community resilience. Investing in air quality monitoring, early warning systems, and protective infrastructure will be critical in reducing the devastating toll of wildfires on both human health and the environment. Without decisive action, the increasing intensity of wildfires will continue to threaten lives, destroy communities, and disrupt ecosystems on a global scale.

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