As some of you may have read in the previous issue of Vetaffairs, I have recently been appointed to the new role of Deputy Chief Health Officer, assisting DVA’s Chief Health Officer, Dr Jenny Firman. Dr Firman and I will be taking turns in writing this column. I am currently acting Chief Health Officer.
While the fires brought terrible suffering, it was inspiring to see how communities pulled together and supported each other through such challenging times.
Many areas not immediately impacted by fires experienced unusually long periods of poor air quality — something we are not used to in Australia. As a result, many people have raised concerns about the possible impacts of this on their health. While the bushfire season is over, sadly the issue of bushfire smoke is likely to be a recurring one. Please note that the following comments do not apply to those involved in firefighting or directly at the fire front.
Bushfire smoke is a form of air pollution, the health effects of which have been extensively studied over the past few decades. The challenge with studies on air pollution is that they provide evidence on health effects for whole populations from which it is impossible to extrapolate to the level of individual risk.
Most of the world’s air pollution is produced by human activity, mainly through the combustion of fossil fuels for the generation of energy. However, natural occurrences such as bushfires and volcanic explosions can produce sudden and extremely high levels of air pollution.
Most people who are exposed to bushfire smoke will notice symptoms caused by the larger particles that affect our upper airways and eyes — symptoms like itchy eyes, a runny nose and sore throat. Though irritating, these symptoms are not harmful and will disappear when exposure stops.
While the vast majority will suffer no serious problems, some people are potentially more susceptible to serious health effects from bushfire smoke, in particular effects caused by the smaller particles known as PM 2.5. These tiny particles, too small for us to notice, have a diameter of less than 2.5 microns, which is about 1/30th the width of a human hair. These tiny particles can travel far into our respiratory systems and even into our blood stream. Studies have shown that some people, including those with pre-existing heart and/or lung disease, may be more sensitive to the negative effects of these particles. For people with underlying heart disease, exposure to smoke may increase the risk of chest pain, heart attacks or palpitations. Those with chronic airways disease or asthma may experience a flare-up. Taking your prescribed cardiac or respiratory medication as directed is particularly important when the air quality is poor, as is having an asthma or chronic airways disease action plan in place. Other groups considered to be potentially more sensitive to the effects of smoke include young children, pregnant women and the elderly. It is recommended that they minimise exposure to smoke.
It is impossible to predict if you personally will be affected, so anyone who may be sensitive is advised to minimise their exposure as far as is practical. From a comfort perspective, most people will feel the need to minimise their exposure when air quality is particularly bad.
Minimising exposure is the best way to protect yourself from any potential ill effects of bushfire smoke. Practical measures include staying inside (this may mean at home or in alternative well-sealed and air conditioned locations), avoiding outdoor exercise when air quality is poor, using an air purifier, and following air quality information and behavioural advice. Australia’s Chief Health Officer has stated that masks are not recommended for general community use, and should be limited to those with significant health issues, outdoor workers or people returning to their properties in burned areas.
There are several free apps that provide real time air quality readings and advice, such as Air Visual or Air Rater. Your state or territory health department website is also a good source of information, as is the federal Department of Health website, for instance the ‘Chief Medical Officer’s and State and Territory Chief Health Officers’ guidance on health effects of exposure to bushfire smoke’ page.
There is currently no evidence about the possible long-term effects of short exposures to high levels of pollution. A recent study of travellers spending a few weeks in highly polluted cities in Asia found that though many experienced respiratory symptoms and a small decrease in lung function while overseas, their symptoms resolved and lung function returned to normal on return to their home country — a very reassuring result.
Until next time, stay well.