Many firefighters will by now be exhausted, having been on the front line of Australia’s bushfire crisis for weeks or months.
This bushfire season has been unrelenting, and the hottest months of summer may still lie ahead.
In part, the toll is physical. The flames are high, they are intense, and they move fast. It’s hard to breathe because the air is so hot.
At the same time, first responders have witnessed widespread devastation. To land and livelihoods, to people and animals. Meanwhile, grief for the death of fellow firefighters feels raw, and the risk to their own lives very real.
We’re right to be concerned about firefighters’ mental health.
Emergency responders already have poorer mental health
Every 4.3 weeks, a firefighter, paramedic or police officer dies by suicide – and that’s when it’s “business as usual”.
Research shows our first responders are more likely to be diagnosed with a mental health condition than the overall Australian population. They are more than twice as likely to think about suicide, and three times as likely to have a suicide plan.
This paints a grim picture of the well-being of a population who dedicate their professional lives to helping others.
It’s likely responding to a disaster on the scale of the current bushfires could increase the risk of mental illness for some.
If firefighters are not coping, they may develop psychological disorders including post-traumatic stress disorder (PTSD), anxiety, depression, and substance abuse.
PTSD develops when a person isn’t able to recover after experiencing a traumatic event.
Some firefighters may develop symptoms while they’re still fighting the fires. They may feel on edge, but push down their fears to get on with the job. However, it’s more likely symptoms will only appear weeks, months, even years down the track.
PTSD is associated with significant impairment in day-to-day functioning socially and at work. For firefighters and others with PTSD, typical symptoms or behaviours will include:
reliving the traumatic event. People with PTSD describe vivid images and terrifying nightmares of their experience
avoiding reminders of what happened. They may become emotionally numb and isolate themselves to avoid any triggers
being constantly tense and jumpy, always looking out for signs of danger.
Volunteers in regional communities are particularly susceptible to trauma. They have often joined fire brigades to help protect their own communities, and then face trying to save their own homes or those of neighbours and friends.
We also need to be mindful of retired firefighters for whom these current bushfires will have triggered painful and disturbing memories. They may not currently be on the front lines, but they only need to turn on the television, open the newspaper, or look at social media to be taken straight back to Black Saturday or whatever particular event is distressing for them.
The problem with reaching out
The increased prevalence of mental health issues among emergency responders suggests many existing emergency service well-being programs are failing those who need them the most.
In Australia, these programs are largely based on a what’s called a “resilience model” that focuses on people “reaching out” and seeking help when they need it.
First responders may be unlikely to take this initiative in the middle of a mental health crisis, when it’s often a struggle even to pick up the phone to a loved one, friend or colleague.
Instead, we need an approach to well-being that removes the onus on the individual. We need to shift our thinking from a model that requires the individual to “reach out”, to a model that also values others “reaching in” to identify those who may be struggling.
Ambulance Victoria’s Peer Support Dog Program, which allows staff to bring in accredited dogs to create social interactions and conversations, is a good example of how “reaching in” helps with first responder well-being. This kind of approach empowers people through social connections and the appreciation they are also supporting others.
While employers need to do more in to facilitate “reach in” programs, anyone can create informal support networks. Whether friendship groups, community groups, sporting groups, or something else, the underlying thread should be a committment to each other’s well-being.
As we continue to contend with this crisis, ensuring firefighters feel supported can make a difference to their well-being. If you see a responder in the street, say thank you. If you see one in a cafe, shout them a cuppa. If you have kids, get them to write a letter or draw a picture and drop it off to the local emergency services station.
We can’t eliminate the risk firefighters will suffer with mental health problems after what they’ve been through, but these little acts of kindness can make a difference.
If this article has raised issues for you, or if you’re concerned about someone you know, call Lifeline on 13 11 14.
You’re scrolling through your phone and transfixed by yet more images of streets reduced to burnt debris, injured wildlife, and maps showing the scale of the fires continuing to burn. On the television in the background, a woman who has lost her home breaks down, while news of another life lost flashes across the screen.
You can’t bear to watch anymore, but at the same time, you can’t tear yourself away. Sound familiar?
We’ve now been confronted with these tragic images and stories for months. Even if you haven’t been directly affected by the bushfires, it’s completely normal to feel sad, helpless, and even anxious.
Beyond despairing about the devastation so many Australians are facing, some of these emotions are likely to be symptoms of “eco-anxiety”.
If you’re feeling down, you’re not alone
Research on previous bushfire disasters shows people directly affected are more likely to suffer mental health consequences than those who have not been directly affected.
After Black Saturday, about one in five people living in highly affected communities experienced persistent post-traumatic stress disorder (PTSD), depression or psychological distress.
Recognising this as a critical issue, the Australian government has announced funding to deliver mental health support to affected people and communities.
But living in an unaffected area doesn’t mean you’re immune. In addition to contending with rolling images and stories of devastation, we’ve seen flow-on effects of the bushfires reach far beyond affected areas.
For example, schools and workplaces have been closed, people have been forced to cancel their summer holidays, and sports matches and community events have been called off. This disruption to normal activities can result in uncertainty and distress, particularly for children and young people.
What is eco-anxiety?
Distress around the current fires may be compounded by – and intertwined with – a pervasive sense of fear and anxiety in relation to climate change-related events.
The American Psychological Association defines eco-anxiety as “a chronic fear of environmental doom”.
While concern and anxiety around climate change are normal, eco-anxiety describes a state of being overwhelmed by the sheer scale, complexity and seriousness of the problems we’re facing. It can be accompanied by guilt for personal contributions to the problem.
The Australian bushfires may have signalled a “tipping point” for many people who held a passive attitude towards climate change, and even many who have held a more active view of climate denialism. In the face of current circumstances, the crisis of climate change now becomes almost impossible to ignore.
While eco-anxiety is not a diagnosable mental disorder, it can have significant impacts on a person’s well-being.
Whether you think you’re suffering from eco-anxiety or more general stress and depression about the bushfires, here are some things you can do.
We’re pretty resilient, but support helps
We’re now living with the environmental consequences of a changing climate, and this requires people to adapt. Fortunately, most of us are innately resilient and are able to overcome stress and losses and to live with uncertainty.
We can enhance this resilience by connecting with friends and family and positively engaging in our communities. Making healthy choices around things like diet, exercise and sleep can also help.
Further, supporting those who are vulnerable has benefits for both the person giving and receiving assistance. For example, parents have a critical role in listening to their children’s concerns and providing appropriate guidance.
Become part of the solution
Seeking to reduce your own carbon footprint can help alleviate feelings of guilt and helplessness – in addition to the positive difference these small actions make to the environment.
This might include walking, cycling and taking public transport to get around, and making sustainability a factor in day-to-day decisions like what you buy and what you eat.
Joining one of the many groups advocating for the environment also provides a voice for people concerned about the changing climate.
Finally, there are many ways you can provide assistance to bushfire relief efforts. The generosity shown by Australians and others internationally has provided a sense of hope at a time when many are facing enormous hardship.
Seeking professional help
Some people, particularly those living with unrelated psychological distress, will find it harder to adapt to increased stress. Where their emotional resources are already depleted, it becomes more difficult to accommodate change.
Although we don’t yet have research on this, it’s likely people with pre-existing mental health problems will be more vulnerable to eco-anxiety.
If this is you, it’s worthwhile seeking professional help if you feel your mental health is deteriorating at this time.
Whether or not you have a pre-existing mental health disorder, if you’re feeling depressed or anxious to a degree it’s affecting your work, education or social functioning, you should seek advice from a health professional.
Evidence-based psychological interventions like cognitive behavioural therapy reduce symptoms of anxiety and depression, improving mental health and well-being.
If this article has raised issues for you, or if you’re concerned about someone you know, call Lifeline on 13 11 14.
As we continue to contend with smoke haze in various parts of the country, many Australians may find themselves with watery, burning, irritated or red eyes.
Data from countries with consistently poor air quality suggest there could also be a risk of longer term effects to our eyes, particularly with prolonged exposure to bushfire smoke.
Although P2/N95 masks can protect us from inhaling harmful particles, unfortunately they can’t protect our eyes.
But there are certain things you can do to minimise irritation and the risk of any longer term effects.
Irritation in the short term
The eye’s surface is continuously exposed to the environment, except when our eyes are shut when we sleep.
Bushfire smoke contains dust, fumes (such as carbon monoxide and nitrogen oxides), and tiny particles called PM10 and PM2.5.
When the smoke comes into contact with our eyes, the fumes and small particles dissolve into our tears and coat the eye’s surface. In some people, this can trigger inflammation, and therefore irritation.
The presence of a marker called matrix metalloproteinase-9, or MMP-9, indicates the eye is inflamed.
During periods of poor air quality from bushfires in the United States, MMP-9 was present in the eyes of more people than it ordinarily would be.
Longer term risks
We know very little about how pollution from bushfire smoke might affect our eyes over the longer term, or what damage repeated or chronic exposure might do.
But we do know people who live in areas with high levels of air pollution, such as China, are three to four times more likely to develop dry eye.
Dry eye is a condition where a person doesn’t have enough tears or they are of such poor quality they don’t lubricate and nourish the eye. We need high quality tears to maintain the health of the front surface of the eye and provide clear vision.
For people who already have dry eyes – often older people – poor air quality may increase the damage. The smoke and pollution may cause intense stinging and a feeling of grittiness to the point they can barely open their eyes.
While dry eye is a result of damage to the surface of the eyes, it’s also possible pollutants entering the blood stream after we breathe them in could affect the blood supply to the eye. This in turn could damage the fine vessels within the eye itself.
Research has suggested high levels of air pollution in Taiwan may increase the risk of age-related macular degeneration, which could be an example of this.
We need more research into the long-term effects on our eyes of prolonged poor air quality, particularly from bushfire smoke. But what we do know suggests it’s possible bushfire smoke could be causing subtle damage to the eyes, even in people without any symptoms.
What can you do to protect your eyes from the smoke?
- the best option is to avoid going outside when air quality is at is worst, where possible
- wearing sunglasses or glasses when outside if you need them might stop some of the dust carried in the wind from contacting the eye’s surface (but it won’t stop the tiny particles getting in)
- avoid wearing contact lenses if possible.
Some tips if your eyes are irritated
- flush your eyes as often as you can, with over-the-counter lubricant eye drops if you have some on hand. If not, use sterile saline solution or clean bottled water
- if your eyes are itchy, flush them and then place a cool face washer over your closed lids
- don’t rub your eyes, as this could make the irritation worse.
If your eyes are red and sore and these steps don’t help, it’s best to see an eye care professional.
As bushfire smoke blankets large parts of Australia, it’s time to examine what this complex chemical mixture is made of, to better understand what it’s doing to both our bodies and the planet.
I research the chemical processes that create pollutants in flames, and what happens when they are released into the air we breathe.
Bushfires are not the only source of smoke we are exposed to in our everyday lives. We breathe smoke from cigarettes, wood-fired heaters, coal-fired power stations and vehicles.
But smoke stemming from the bushfires is accumulating over cities in concentrations rarely seen before in Australia, badly affecting cities including Sydney, Melbourne and Canberra. This poses risks to public health and the environment. Read on to find out exactly what you’re breathing in.
It’s largely water
First, there is a lot of water in bushfire smoke. When fire rips through a forest it burns off the water held in the trees, sending rolling clouds of steam up into the atmosphere.
Water might seem harmless, but it actually enables bushfires to form their own weather. Water vapour condenses on smoke particles and forms huge pyrocumulonimbus clouds. We saw these storms in the current fire crisis. They can complicate firefighting efforts by producing wind and lightning strikes but unfortunately rarely bring rain.
These clouds also inject smoke high into the atmosphere from where it can circle the globe. We recently saw this when smoke from bushfires in Australia’s south-east drifted to New Zealand and then on to South America. Smoke lofted into the stratosphere influences the climate by blocking the movement of light and heat, and can even interfere with chemistry in the ozone layer.
The climate effect
Smoke also contains gases, most notably carbon monoxide (CO) and carbon dioxide (CO₂). Carbon dioxide is the end-product of combustion and is the most significant contributor to man-made global warming.
Forests sequester massive amounts of carbon as wood and other organic matter and much of this is released back into the atmosphere as carbon dioxide when burned.
Within about a year, these molecules could be anywhere in Earth’s atmosphere. CO₂ is so long-lived that many of these same molecules will remain circling the globe for hundreds of years.
This bushfire season, more than 10 million hectares of land has already burned. Estimates based on satellite data put the subsequent CO₂ release at 400 million tonnes. This is close to Australia’s total annual greenhouse gas emissions of around 500 million tonnes of CO₂ equivalent.
Our planet’s climate emergency is already making Australia hotter and drier, with more frequent extreme weather events. The ensuing fires are in turn releasing carbon back into the atmosphere, forming a dangerous positive feedback loop.
The poisonous sibling
Whereas CO₂ presents a long-term threat to us all, its poisonous sibling carbon monoxide (CO) is a more immediate concern to those directly exposed to smoke. Carbon monoxide forms when combustion is interrupted on its way to make carbon dioxide.
At the high concentrations found in smoke, carbon monoxide can be deadly. It binds strongly to our haemoglobin – the molecule in red blood cells that carries oxygen around the body. At around 100 parts per million in air it can starve the human body of oxygen, asphyxiating its victims.
Carbon monoxide poisoning through smoke inhalation is a direct concern to firefighters and those sheltering from flames. Those fighting bushfires often work long shifts, sometimes over several weeks, with face masks that offer limited protection.
But that’s not all
In addition to these two gases, smoke contains trace levels of many other pollutants such as sulfur dioxide (SO₂) and nitrogen dioxide (NO₂). In a bushfire, these are produced through the burning of sulfur and nitrogen in plants.
(These gases are also produced through burning fossil fuels. Over eons, ancient trees fossilise into oil and coal but retain some sulfur and nitrogen).
Both SO₂ and NO₂ irritate our respiratory system. Atmospheric SO₂ is also problematic because over time it gets converted in air into sulfuric acid, forming acid rain. NO₂, on the other hand, breaks down in sunlight causing harmful ground-level ozone to form.
We are still learning about other dangerous trace gases in smoke. For instance, in the last decade we have come to realise that highly toxic isocyanic acid from smoke can be present in urban air at concentrations approaching those which are known to impact our health. Unfortunately, little research is available for Australian conditions.
Don’t forget the tiny particles
The final component of smoke we need to consider are the solid particles, or particulate matter (PM). This is both soot that builds up during combustion, and ash that breaks down from the remnants of burnt fuel.
What we see following a bushfire are mostly the larger particles, which reduce visibility and settle on cars and buildings. But the most dangerous component to our health are microscopic particles around one millionth of a metre in size.
These particles can penetrate deep into our lungs and make their way into our bloodstream, potentially impacting almost every bodily system.
Moreover, because of their size they are more likely to stay aloft in air and be transported away from their source.
Particles smaller than 2.5 micrometres, known as PM2.5, settled on Canberra in recent weeks – a problem so severe on some days the city could lay claim to having the most polluted air in the world.
Bushfire smoke is a complex chemical mixture that can affect humans in many ways. As fires become increasingly common across our continent, we must become more familiar with what we are breathing in.
Australia’s unique vulnerability to climate change, as has been evident this bushfire season, means we should also lead the world in reducing greenhouse gas emissions.
At the same time, Australians need to adapt. This means equipping our buildings with sensors and purifiers to respond to air pollution and educating the public on how to stay safe during an air quality emergency. It’s clear we must prepare for many smoke-filled summers to come.
As bushfire smoke continues to pollute the air of large parts of Australia’s eastern states, some people have experienced throat irritation, coughing and breathing difficulties.
Health authorities have also warned more severe symptoms such as chest tightness and wheezing may emerge in people who have underlying asthma and in people who haven’t yet been diagnosed.
Wheezing is a high-pitched whistling sound when you breathe, caused by muscle spasm or inflammation in narrowed airways.
Normal response to bushfire smoke
Respiratory symptoms can occur in otherwise healthy people in response to bushfire air pollution. This is due to large and small particulates in fire smoke irritating the the thin lining of the respiratory tract, called the mucous membrane.
These particles tend to cause increased secretions, inflammation and irritation of the eyes nose and throat, even in people who have no history of lung disease.
Why it’s important to know your asthma profile
Asthma is an inflammatory disease which causes narrowing of the airways. Symptoms and flare-ups or attacks can occur after exposure to a wide range of triggers.
If the airway inflammation isn’t treated, it can progress to more significant and permanent airway narrowing that results in persistent breathlessness and loss of lung function.
If you have asthma, it’s most important to know the severity, how to control it, and how to identify and promptly treat an attack.
What might signal undiagnosed asthma?
People with asthma can experience severe attacks or flare-ups when exposed to bushfire smoke, or persistent respiratory symptoms that don’t settle promptly after their smoke exposure ends.
Symptoms that suggest the possibility of asthma include chest tightness and wheezing in response to exposure to irritants such as smoke, dusts, aerosol sprays and fumes, or in response to allergic triggers such as pollens, cat and dog fur, house dust, and mouldy atmospheres.
Asthma can also manifest as a cough.
Many people with asthma have a history of hayfever, often provoked by pollens, house dust, cat and dog fur, and moulds.
People with a family history of asthma are at greater risk of developing the disease, as are those with a history of wheezing illness in childhood caused by viral respiratory infections. In fact, viruses that cause the common cold are frequent triggers of asthma attacks.
Some people with asthma may experience symptoms predominantly when they exercise. In such cases, chest tightness and wheezing typically occurs while exercising but often intensifies over a few minutes after stopping.
What to do if you’re unsure
If you experience symptoms of asthma from the bushfire smoke, see your GP.
To assess whether you have asthma, your doctor will undertake a breathing assessment called called a spirometry test. This requires you to blow into a mouthpiece to assess how much air you can blow out and how quickly you can expel the air.
The doctor will also determine whether there is airway narrowing which improves after taking a bronchodilator – a reliever medication such as Ventolin.
It’s not OK to just take asthma medicines, gain some benefit and conclude you have the condition. Many respiratory symptoms can easily be mistaken for asthma, particularly when they occur in association with viral respiratory infection.
How is asthma treated?
Many people believe their asthma is being treated if they use their blue reliever inhaler as needed.
But relievers don’t address the underlying airway inflammation, even though they relieve the symptoms. They should never be used as a daily medication for asthma.
Asthma treatment requires an anti-inflammatory medication, usually an inhaled corticosteroid taken regularly. These medications control the underlying inflammatory process and prevent symptoms and attacks.
Anti-inflammatory treatments are effective in maintaining asthma control day by day so that even with smoke and air pollution exposure, symptoms and attacks are less likely to occur.
People with asthma should have a written action plan which identifies symptoms that typically occur during asthma flare-ups and enables patients to increase their medications appropriately.
Finally, because asthma is a chronic inflammatory condition it requires monitoring and regular review. In these reviews, your doctor will check your lung function and ensure you’re taking the right medication and that your action plan is up to date.
Thousands of families with babies and toddlers have been affected by Australia’s bushfire disaster. This includes children whose homes have been under direct threat or impacted by severe smoke pollution, or where their parents volunteer or work as fire fighters.
Babies and toddlers may not be aware of the danger the fires pose to them or their families. But they find changes in their environment distressing and may notice the stress of their caregivers.
Routine and predictability makes young children feel safe. Evacuating, travelling long distances, noisy evacuation centres and staying in crowded or temporary accommodation disrupts this predictability.
Kids communicate with behaviour, not just words
Babies and toddlers can’t easily communicate they’re unsettled with words so they show it in their behaviour. This might include:
babies feeding more frequently and being unsettled during feeds
toddlers wanting to eat more or not wanting to eat at all
wanting to be held more and and showing increased clinginess
difficulty in going to sleep and waking more frequently during day and night sleeps
regressions in learnt behaviours such as sitting, crawling and walking
being whingey and wanting more attention, or being easily distressed or withdrawn.
When parents are stressed, they find it more difficult to notice their baby’s or toddler’s behavioural communications.
In the acute phase of an emergency, it may not be possible to respond to a baby or toddler. Very young children can find this extremely stressful.
How to help your child cope
If your baby or toddler is showing signs of distress, provide them with responsive care. This involves watching and noticing their behavioural cues, including body movements and sounds, and responding to this communication in a nurturing way.
The behavioural changes you see in your child provide you with information about what they need.
A baby or toddler who doesn’t want to go to anyone but their mother is communicating that, right now, mum represents safety and only mum will do.
A child who is waking at night is saying, “I’m scared. I need you near to reassure me when I wake.”
A child who is demanding or withdrawn is indicating they need more attention, not less.
Try not to worry too much about feeding issues. Allow babies and toddlers to eat when they indicate hunger. Offer food frequently but don’t try force your toddler to eat.
Keeping your baby or toddler physically close will help you to notice their cues and provide responsive care. Baby slings can help parents do this while they get on with other things.
Consider delaying any changes that you were considering before the fires, such as starting solid foods, introducing a bottle, giving up the dummy, starting childcare or moving the child out of your bedroom. When things have settled down again, your baby or toddler should once again be able to manage these changes.
If you feel you’re struggling to provide responsive care to your baby or toddler, ask your family or friends for extra help or contact your child health nurse or doctor.
Breastfeeding mothers – stress won’t reduce your supply
Changes in babies’ feeding and sleeping behaviour during emergencies can be particularly concerning to breastfeeding mothers who worry the stress will affect their milk supply.
Research tells us stress has no impact on milk production. But it can slow the release of milk, making babies fussy at the breast.
If this happens, keep offering breastfeeds. While feeding, focus on your baby and think about how much you love them. This will release hormones that make the milk flow and help you and your baby to feel more relaxed.
We all need to support parents through this disaster
Helping babies and toddlers to recover from an emergency shouldn’t just be left to parents. Those around families with babies and toddlers can help by cleaning or cooking, allowing parents to prioritise caring for their children and other pressing tasks.
The impact of an emergency can persist for some time. If you feel you’re still affected by the disaster, your baby or toddler might feel that too. Give them and yourself time. Babies and toddlers usually recover well after emergencies. Your love and responsive care is the key.
Karleen Gribble, Adjunct Associate Professor, School of Nursing and Midwifery, Western Sydney University and Nina J Berry, Post-doctoral Research Associate, Sydney School of Public Health, University of Sydney
Amid thick bushfire smoke in cities including Canberra and Melbourne, employers need to consider their legal obligations.
Some have directed their workers not to turn up in order to avoid to occupational health and safety risks. Among them is the Commonwealth department of home affairs which last week asked most of its staff to stay away from its Canberra headquarters for 48 hours.
Other employers want to know where they stand.
Each state and territory has its own occupational health and safety laws.
However most line up with the so-called Model Act, a federal act of parliament intended to harmonise state laws.
Under section 17 it imposes on employers a duty to, so far as is reasonably practicable, ensure health and safety by eliminating or minimising risks.
This employer’s duty applies not only to its employees, but also to other types of workers including independent contractors.
Meaning of ‘reasonably practical”
Under the section 18 of the Model Act, “reasonably practicable” means
that which is, or was at a particular time, reasonably able to be done in relation to ensuring health and safety, taking into account and weighing up all relevant matters
By themselves, these words aren’t much of a guide, so the Act includes examples of “relevant matters”, among them:
the likelihood of a hazard or risk occurring
the degree of harm that might result
what the employer knows or ought reasonably know about the hazard or risk, and ways of eliminating or minimising hazard or risk
the availability and suitability of ways to eliminate or reduce hazard or risk
the cost associated with available ways of eliminating or minimising the risk, including whether the cost is grossly disproportionate to the risk
Meaning of ‘likelihood’
Employers should make themselves aware of the risk of an air quality hazard.
This can be achieved by checking the most up to date air quality index in the location on an environment protection authority website:
Workers who work outdoors are more likely to be subject to harmful effects of bushfire smoke than indoor workers.
They are more likely to experience irritation to their airways, nose and eyes.
They might also experience low visibility which might make their work more dangerous.
The machines they operate could also be impacted by the smoke and dust in a way which would make operating them more dangerous.
Special measures should be taken to protect workers who work outdoors, such as providing them with face masks or rescheduling their work.
Meaning of ‘degree of harm’
It is certainly arguable the likelihood of harm for indoor workers is much lower, especially if the air quality in their workplace is the same or even better than the air quality in their homes.
Employers should have up-to-date information about the health of their workers, especially those workers who have pre-existing conditions that might predispose them to harm from smoke.
Among these would be workers who have asthma or other respiratory disorders.
Special steps should be taken to protect them, taking into account their pre-existing conditions.
Meaning of ‘reasonably ought to know’
Employers should be checking up-to-date information on an environment protection authority website and on the website of Safe Work Australia which is the Commonwealth regulator for occupational health and safety laws.
It’s very likely law enforcers will presume the information on these websites constitute information the employer ought to have known in determining the appropriate action to take.
For example, it would be difficult for an employer to argue they didn’t know P2 rated face masks should be provided to workers when the Safe Work Australia website specifically mentions them as an appropriate way of eliminating or reducing air quality hazards.
Meaning of ‘availability of ways to reduce risk’
Safe Work Australia directs employers to have in place measures to manage the risks to health and safety of working outdoors when air quality is reduced, including:
working indoors (where possible)
rescheduling outdoor work until conditions improve
ensuring buildings and equipment are functioning correctly and have not been affected by dust or debris
cleaning dust and debris off outdoor surfaces
providing personal protective equipment such as eye protection and correctly fitted P2-rated face masks.
Meaning of ‘cost of minimising hazard’
The cost of elimination or minimising hazard will be higher for some measures than others.
For example, it might cost more to direct workers to stay home than to provide face masks.
These costs need to be weighed up against the likelihood and degree of potential harm.
If the likelihood and degree of harm is high, it’s unlikely law enforcers will be particularly sympathetic to arguments about cost.
In previous years, Australians might have been exposed to bushfire smoke for a few days, or even a week. But this bushfire season is extreme in every respect. Smoke haze has now regularly featured in Australian weather reports for several weeks, stretching across months in some areas.
What we considered to be short-term exposure we must now call medium-term exposure.
Given this is a new phenomenon, we don’t know for sure what prolonged exposure to bushfire smoke could mean for future health. But here’s what air pollution and health data can tell us about the sorts of harms we might be looking at.
We know poor air quality is having immediate effects, from irritated eyes and throats, to more serious incidents requiring hospital admission – particularly for people with existing respiratory and heart conditions.
After the smoke haze hit Melbourne on Monday, Ambulance Victoria recorded a 51% increase in calls for breathing difficulties.
This aligns with Australian and international research on the acute effects of exposure to bushfire smoke.
But the long-term effects aren’t so clear.
Long-term effects: what we know
When considering the long-term health consequences of air pollution, we draw on data from heavily polluted regions, typically in Africa, or Asia, where people are exposed to high levels of airborne pollution for years.
It’s no surprise long-term exposure to air pollution negatively affects health over their lifetime. It’s associated with an increased risk of several cancers, and chronic health conditions like respiratory and heart disease.
The World Health Organisation estimates ambient air pollution contributes to 4.2 million premature deaths globally per year.
A recent study in China reported long-term exposure to a high concentration of ultrafine particles called PM2.5 (which we find in bushfire smoke) is linked to an increased risk of stroke.
We also know the dose of exposure is important. So the worse the pollution, the greater the the health effects.
It’s likely some of these long-term effects will occur in Australia if prolonged bushfires become an annual event.
Observational studies, like the Chinese one mentioned above, demonstrate the long-term health effects of long-term exposure to air pollution. But we don’t really have any studies like this following populations which have experienced short- or medium-term exposure.
These studies follow the models for days (short-term) or weeks (medium-term). They show exposure to any type of airborne pollution – from traffic, bushfires, wood or coal smoke – is detrimental for health.
What about bushfire smoke?
We don’t have a lot of experimental data on the effects of bushfire smoke specifically, apart from a few studies on cells in the lab.
In my lab we’ve found the short-term in-vitro effects of bushfire smoke are comparable to the smoke from cigarettes. This does not however mean the long-term heath effects would be the same.
If we think about what’s burning during a bushfire – grass, leaves, twigs, bushes and trees – it’s also reasonable to draw on experimental data from wood smoke.
In one small study, ten volunteers were exposed to wood smoke for four 15 minute periods over two hours. Afterwards, participants experienced increased neutrophils, a type of aggressive white blood cell, in both their lungs and circulation. The concentration of particulate matter in the wood smoke was lower than the levels we’ve seen in Sydney.
These short term studies show bushfire smoke is toxic, and it’s this toxicity which is likely to cause long-term effects.
One review found lifelong exposure to wood smoke, for example from indoor heaters, is associated with a 20% increased risk of developing lung cancer. Though it’s important to remember this is long-term exposure; the risks associated with medium-term exposure are not yet known.
How can we apply these findings?
Taking data from one type of airborne pollution and applying it to different pollutants – for example comparing the smoke from only one type of wood to bushfire pollution – is complex. The chemical make up is likely to differ between pollutants, so we need to be cautious extrapolating results.
We also need to be wary about how we translate results from cell and animal studies to humans. Different people are likely to respond to bushfire smoke differently. Our genetic make up is important here.
And with variable factors like at what age the exposure starts, how long it lasts, and other factors we’re exposed to during our lives (which don’t exist in a petri dish), it’s difficult to ascertain how many people will be at risk, and who in particular.
Looking past the haze
The human body actually has a remarkable capacity to cope with air pollution. It appears our genes help protect us from some of the toxic effects of smoke inhalation.
But this doesn’t mean we’re immune to the effect of bushfire smoke; just that we can tolerate a certain amount.
So would a once in a lifetime medium-term exposure have a chronic effect? At the moment there’s no way of answering this.
How rising temperatures affect our health
But if, as many people fear, this medium term exposure becomes a regular event, it could cross into the long-term exposure we see in some countries, where people are exposed to poor air quality for most of the year. In this scenario, there’s clear evidence we’ll be at higher risk of disease and premature death.
For now, we desperately need studies to help us understand the effects of medium-term exposure to bushfire smoke.