The invisible killer lurking in the skies of our cities

Annual exposure to high levels of air pollution kills more than a million people every year. And while Asia and Africa are particularly at risk, Australia is not immune to this danger.

With smog and forest fires becoming more common due to climate change, more people are likely to die from air pollution in the coming years, especially in densely populated cities.

These are some of the key findings from our recent research, published in Lancet Planetary Health last month.

Bushfires and emissions are putting the health of Australians at risk

Australia generally has excellent air quality, being one of only seven countries that meet the clean air standards set by the World Health Organization (WHO).

But there’s a catch. Sometimes air pollution in Australia rises significantly – and breathing that polluted air can make us sick.

Wildfires, especially in summer, are a major reason for these pollution spikes. These fires emit smoke and small harmful particles into the air, deteriorating air quality.

For example, researchers found that during the 2019-2020 ‘Black Summer’ bushfires, air pollution was fifteen times worse than levels considered safe by the WHO. This bad air was linked to 429 people dying earlier than they otherwise would have – and more than 3,000 people ending up in hospital due to respiratory or heart problems caused by smoke.

Dust storms and emissions from industries and vehicles also contribute to these pollution spikes. When there is a lot of activity in factories or more cars and trucks on the roads, the amount of pollution released into the air can quickly increase.

Air pollution doesn’t just make it difficult to breathe. It can also damage other parts of the body, including the heart, blood vessels and brain.

One of the smallest troublemakers in the air are small particles known as ‘particulate matter’ (PM_2.5). These particles – which are smaller than a red blood cell – can travel deep into your lungs and even into the blood, affecting our health. WHO says PM_2.5 is one of the most harmful particles to health, affecting more people than any other pollutant.

If you are exposed to a lot of this pollution for a short period of time, problems such as asthma can worsen and you may experience coughing, wheezing or shortness of breath.

Being around too much air pollution for even a short time – just a few hours or days – can accelerate health problems with your lungs and heart, increasing the likelihood that you’ll need to go to the hospital or even risk death gets bigger.

Short-term exposure can be serious

Air pollution can affect anyone, but is especially risky for children, pregnant women and the elderly. This is especially true when cities are hit by short, intense bursts of dirty air. (Both long-term and short-term exposure are harmful to human health. Long-term exposure is generally thought to contribute to a greater mortality burden than short-term exposure due to its cumulative effect on health.)

Cities are often warmer than rural areas due to a condition called the “urban heat island effect.” It can make the air still and not move much anymore. In urban areas with large populations, especially those who may already be sick or vulnerable, more people may die from short spikes in air pollution.

Asia and Africa are responsible for almost 80% of all deaths from air pollution. Furthermore, according to a recent global study, more than a fifth (22.74%) of these deaths occur in cities.

Before this Monash University study, scientists had mainly looked at how breathing polluted air over long periods of time affects people’s health. They hadn’t paid much attention to the sudden increase in pollution that can occur due to things like forest fires, dust storms or other unusual events, especially in smaller towns and cities.

The study was the first time we really examined how these short spikes in air pollution can be deadly around the world.

It monitored the air in more than 13,000 cities and towns around the world, from the past two decades through 2019. It sheds light on how dangerous this temporary increase in pollution can be.

Asia is suffering the worst

Asia faces the heaviest toll in terms of deaths from particulate matter air pollution in the short term, accounting for approximately 65.2% of these deaths (“global mortality”).

Africa and Europe follow, with 17% and 12.1% of global deaths. America had a relatively lower impact, accounting for 5.6% of these deaths.

China, and especially its cities, has had the highest death toll in the past two decades due to short-term spikes in air pollution. Countries in South Asia such as Bangladesh, India and Pakistan have seen a rapid increase in these deaths, propelling them up the global rankings.

Now the good news for Australians: according to the research, Australia and New Zealand had some of the lowest rates of deaths (0.1%) from acute particulate matter air pollution, with an average of 614 people dying from such pollution between 2000. -2019.

But there’s a catch for Australia. Deaths from this short-lived air pollution increased by 40% in these years, from 0.54% in 2000 to 0.76% in 2019. This increase is likely due to more frequent and intense extreme air pollution events, such as forest fires and dust storms .

Related articles: Air pollution is the biggest environmental killer, claiming 7 million lives | How polluted is the air in Europe? | Smoke from forest fires suffocates indigenous communities | How air pollution can affect antibiotic resistance | Air pollution ‘significantly associated’ with breast cancer incidence | How useful is the air quality index? | Why the European Parliament’s vote on cleaner air rules is not enough

What can we do about air pollution?

The solutions to air pollution don’t simply involve cleaning up the air; they are also about protecting ourselves from the damage pollution can cause.

First, we need to reduce air pollution. This means things like switching to cleaner energy (think wind or solar energy); making things work more efficiently so they don’t waste as much energy and reducing the smoke and fumes from cars and factories.

But sometimes pollution levels can suddenly increase. When this happens, we must stay safe. In some places, there are contingency plans in place if the air gets really dirty, such as limiting car traffic, pausing factory work or even temporarily closing schools.

Staying informed is essential. We need warning systems that tell us when the air is deteriorating and what we can do about it. Learning about air pollution also helps so we know how to protect ourselves. This could lead to guidelines on what to do if air quality drops.

What can you do to protect yourself and your family? If the air outside is bad, try to stay indoors and keep the windows closed to keep the bad air out. If you have to go outside, consider wearing a mask. Use air purifiers to clean the air in your home. And finally, cut back on outdoor activities until the air improves.

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This article was originally published Through 360info™.

Editor’s Note: The opinions expressed here by the authors are their own, not those of Impakter.com — Cover photo credit: Leo.