The health impact of bushfires and preparing for future crises

27 March 2020

Published by https://www.policyforum.net

AUSTRALIA – In the aftermath of Australia’s catastrophic Black Summer bushfires, it is important to assess the multiple impacts of the fires on the Australian society, health, and economy in the short, medium, and long-term.

However, it is even more important to identify gaps and shortfalls in the response to the bushfire crisis, and prepare for an unfolding climate emergency which is likely to increase the risk of extreme fire weather in the future.

The extreme bushfires the nation has experienced in recent months have devastated communities, and caused substantial loss of human and animal life, livelihoods, property, and infrastructure.

One of the major impacts of the fires was on air quality, with Sydney, Canberra, and Melbourne choked with bushfire smoke over prolonged periods. Millions of people were exposed to extremely high levels of particulate air pollution over weeks and months. The smoke travelled long distances, affected large parts of eastern Australia, and even reached New Zealand and Latin America.

Bushfire smoke contains high concentrations of fine particles that penetrate deeply into the lungs, can cross into the blood stream, and cause adverse health effects. They can exacerbate respiratory conditions such as asthma, emphysema, and chronic obstructive pulmonary disease, and cardiovascular conditions such as irregular heart rate, chest pain, myocardial infarction, and cardiac arrest.

Air pollution has also been associated with increased paediatric respiratory visits, slightly reduced newborn birthweight, and increased gestational diabetes risk in pregnant women. Although most of the evidence comes from other sources of air pollution, it is likely that smoke from bushfires will have similar effects on health.

In addition to physical health effects, bushfires and smoke have caused distress and anxiety to those directly at risk of fires, as well as to those exposed to extremely high levels of smoke pollution further afield.

Extreme smoke haze events must be a wake-up call for health authorities and the public. It became clear that the related public health advice – such as ‘stay indoors’ and ‘avoid physical exercise outdoors’ – for dealing with air pollution episodes was not sufficiently nuanced for different population groups, such as young children, pregnant women, people with lung or heart disease, or outdoor workers.

It also became clear that the advice available was tailored for short-term air pollution events, and became impractical as the smoke lingered over large population centres for several days and eventually weeks.

There were also inconsistencies in the way air pollution data were presented and the health advice communicated to the public in different states and territories affected by the smoke.

During the crisis, The Australian National University produced a set of factsheets which provide more nuanced and practical advice on how Australians could protect themselves from the smoke and take care of their mental health after the bushfires.

However, more work is urgently needed in this area to develop an evidence base on the effectiveness of different health protection measures, such as facemasks, air purifiers, and other advice, and their pros and cons. Experts must be able to provide more specific and accurate advice.

Australian cities enjoy relatively good air quality outside the bushfire season. However, it is important to remember that air pollution exposure in all seasons causes premature mortality. Around 2800 deaths, or two per cent of all deaths, are attributable to air pollution in Australia every year.

This pollution comes from all sectors, including road traffic, industry, power generation, and domestic sources. Bushfire smoke only exacerbates this serious public health problem, with the smoke from the recent fires responsible for over 400 excess deaths.

Overall, there is an urgent need for a balanced approach to bushfire risk reduction, which may involve early detection systems and more resources, such as firefighters and equipment, on the ground.

It may also require prescribed hazard reduction burns and other methods to reduce flammable fuel load in forests.

However, policymakers should bear in mind that prescribed burning also produces smoke, and can only be safely conducted in certain vegetation types under specific weather conditions. Furthermore, the safe time window for burns is potentially narrowing due to climate change.

Building long-term resilience to prolonged bushfires requires a better understanding of the causes and effects of air pollution, and of the factors determining personal exposure. Further, consistency of health advice across jurisdictions is essential.

There is an urgent need for an independent national expert committee on air pollution and health protection to be established. It should be tasked with reviewing the scientific evidence and providing authoritative advice on the health effects of air pollution, and, while supporting environmental policy, recommending interventions to protect the public.

This new expert committee should have a clear mandate, and the resources, to develop accurate, practical, and consistent advice on bushfire smoke and air pollution more broadly.

It is likely that climate change will increase the risk of extreme fire events in the future. In addition to drastically reducing carbon emissions to mitigate climate change, Australia must take action to be better prepared to protect the public from bushfires and smoke. The next bushfire season is not as far away as it may seem.