World Asthma Day: Asthma and environmental triggers

Asthma, a chronic respiratory condition characterised by airway inflammation and hyperresponsiveness, affects a significant portion of the Australian population. It is a leading cause of emergency department presentations and hospital admissions among children and a major contributor to respiratory-related hospitalisations in adults. Environmental factors driven by climate change play a crucial role in exacerbating asthma symptoms and triggering potentially life-threatening attacks.

The global reliance on coal, oil, and gas continues to drive greenhouse gas emissions, pushing planetary temperatures to unprecedented levels. Rising temperatures fuel more extreme weather events, including heatwaves, bushfires, and severe thunderstorms, all of which contribute to worsening air quality. These climatic shifts have direct and indirect consequences for respiratory health, particularly for people with asthma. Elevated temperatures and changing weather patterns alter pollen seasons, increase the prevalence of airborne allergens, and intensify air pollution through higher levels of ozone and fine particulate matter (PM₂.₅). Additionally, more frequent and intense bushfires and dust storms release harmful pollutants into the atmosphere, further aggravating respiratory conditions.

The World Health Organization (WHO) reports that 99% of the global population breathes air that exceeds WHO guideline limits, containing high levels of pollutants from industrial processes, transport emissions, and agricultural activities. This exposure is particularly concerning in Australia, where bushfire smoke, vehicle emissions, and seasonal pollen surges intersect to create hazardous conditions for people living with asthma.

Without urgent and sustained reductions in fossil fuel consumption, climate change will continue to escalate, exacerbating the frequency of asthma-related health crises. Nurses and healthcare professionals play a crucial role in advocating for climate action, supporting asthma management strategies, and ensuring communities are informed about environmental risks. This article examines three major climate-driven asthma triggers—air pollution, bushfire smoke, and thunderstorm asthma—highlighting the urgent need for climate adaptation and mitigation within healthcare and public policy.

Air pollution and asthma

Air pollution comprises a mixture of solid particles and gases in the air, including particulate matter (PM), nitrogen dioxide (NO₂), sulphur dioxide (SO₂), ozone (O₃), and carbon monoxide (CO). These pollutants can irritate the airways, leading to increased asthma symptoms and attacks.

In Australia, urban areas often experience elevated levels of air pollution due to vehicle emissions, industrial activities, and other sources. Research indicates that exposure to fine particulate matter (PM₂.₅) is associated with increased hospital admissions for asthma, particularly among children and the elderly. Nurses play a critical role in educating patients about the importance of monitoring air quality forecasts and minimising exposure during high pollution periods.

Long-term exposure to air pollution does more than just trigger asthma symptoms—it has lasting consequences on lung development, immune function, and overall respiratory health. Children exposed to high levels of air pollution from an early age are more likely to develop asthma and suffer from reduced lung function as they grow. Additionally, evidence suggests that prolonged exposure to fine particulate matter (PM₂.₅) and nitrogen dioxide (NO₂) increases the likelihood of developing severe, treatment-resistant asthma, making disease management more complex and costly. For older adults and individuals with existing respiratory conditions, continuous exposure to polluted air is associated with a higher risk of hospitalisation, reduced lung capacity, and increased mortality due to respiratory complications. The cumulative impact of air pollution on lung health underscores the urgent need for proactive interventions, including stricter emissions regulations, improved urban planning to reduce vehicle pollution, and enhanced public health strategies to mitigate exposure.

Bushfire smoke and asthma

Bushfires are a recurrent natural phenomenon in Australia and globally, particularly during hot, dry months. However, climate change is making bushfire seasons longer, more intense, and less predictable. The catastrophic 2025 wildfires in Los Angeles serve as a stark reminder that bushfires are no longer confined to traditional fire seasons—they can now ignite and spread at any time of the year, fuelled by rising temperatures, prolonged droughts, and extreme weather patterns.
The smoke produced by bushfires contains a dangerous cocktail of fine particulate matter (PM₂.₅), carbon monoxide, volatile organic compounds, and toxic chemicals. These pollutants can penetrate deep into the lungs, triggering inflammation, exacerbating pre-existing respiratory conditions, and increasing the risk of cardiovascular disease. Even short-term exposure to bushfire smoke has been linked to heightened asthma symptoms, increased reliance on medication, and a surge in emergency department visits.

A study examining the health impacts of the devastating 2019–2020 Australian bushfires found that asthma-related hospital admissions rose sharply during major smoke events. Alarmingly, despite the well-documented dangers, only 20.4% of people with asthma reported wearing masks to protect themselves from bushfire smoke. This highlights a critical gap in public health messaging and protective behaviours, underscoring the urgent need for better education, access to protective equipment, and stronger air quality policies to safeguard respiratory health in an era of escalating climate-driven disasters.

Protective measures

To mitigate the health impacts of bushfire smoke, individuals with asthma should:

• Stay indoors with windows and doors closed during heavy smoke conditions.
• Use air purifiers with HEPA filters to reduce indoor pollution levels.
• Follow asthma action plans and have medications readily available.
• Consider temporary relocation to areas with better air quality if feasible.

Thunderstorm asthma

Thunderstorm asthma is a phenomenon where specific weather conditions trigger a sudden increase in asthma cases. It occurs when thunderstorms cause pollen grains to burst into smaller particles, which can be inhaled deeply into the lungs.

In November 2016, Melbourne experienced a severe thunderstorm asthma event that resulted in ten fatalities and thousands of emergency department presentations. This event highlighted the need for heightened awareness and preparedness among healthcare providers and the public.

Risk factors and prevention

Individuals with a history of hay fever or pollen allergies are at increased risk during thunderstorm asthma events. Preventative strategies include:

• Regular use of preventer inhalers as prescribed.
• Staying indoors before and during thunderstorms, especially during high pollen seasons.
• Monitoring pollen forecasts and thunderstorm warnings.
• Developing and adhering to an asthma action plan.

The role of nurses in addressing climate-driven asthma

Asthma is a growing public health challenge, and climate change is significantly amplifying its prevalence and severity. Rising temperatures, increasing air pollution, prolonged pollen seasons, and escalating bushfires are all contributing to worsening respiratory health outcomes. Thunderstorm asthma, bushfire smoke exposure, and chronic air pollution are no longer isolated environmental concerns; they are direct consequences of a warming planet and our continued reliance on fossil fuels. If left unchecked, climate change will continue to drive more frequent and severe respiratory crises, placing immense pressure on healthcare systems and disproportionately impacting vulnerable populations.

Nurses, as the largest and most trusted healthcare workforce, are at the frontline of this crisis. They play a crucial role in education, prevention, emergency response, and policy advocacy to protect individuals and communities from climate-driven respiratory threats. Nurses are often the first point of care for patients experiencing acute asthma attacks, and their ability to rapidly assess, treat, and educate patients can make a life-saving difference. However, their role extends far beyond clinical care. By actively engaging in health promotion and education, nurses can ensure that patients understand how to mitigate their risk—whether by monitoring air quality, adhering to asthma management plans, or recognising early warning signs of worsening respiratory symptoms.

Beyond individual patient care, nurses must also champion systemic change. This includes advocating for stronger air quality regulations, equitable access to asthma medications, and increased funding for climate-health research and early warning systems. Importantly, nurses have a powerful voice in policy discussions, and they must continue to push for urgent climate action to reduce fossil fuel emissions—the root cause of these worsening environmental health threats. Climate change is not a distant or abstract issue; it is a present and growing threat to public health, and nurses have an ethical obligation to advocate for sustainable solutions that protect both their patients and the planet.

Past climate-driven disasters that have exacerbated asthma globally, along with the ongoing public health burden of air pollution, serve as stark warnings. Without immediate and sustained action, these events will become more frequent, more severe, and more deadly. As healthcare leaders, nurses must be at the forefront of this fight—not just responding to climate-driven health emergencies but working proactively to prevent them. The health of our communities depends on it.