What are the health impacts of Sydney's bushfire smoke and do face masks help?

The lingering bushfire smoke hanging over Sydney has prompted some to wear face masks outside.

A woman seen wearing a dust mask as smoke haze from bushfires in New South Wales blankets the CBD in Sydney, Tuesday, December 3, 2019. (AAP Image/Joel Carrett) NO ARCHIVING

Some Sydney-siders are wearing face masks to help cope with the smoke. Source: AAP

As dozens of bushfires continue to burn across NSW, smoke haze is expected to be a regular sight this summer.

The smoke has already lingered over Sydney for a record-long period and the Bureau of Meteorology isn’t predicting a return to clear skies for a few days yet.

Apart from obscuring the view, the smoke contains harmful PM2.5 particulants that are tiny enough to be breathed into your lungs and absorbed into the bloodstream.

Commuter ferries sail past the Sydney Harbour Bridge as smoke haze from bushfires in New South Wales blankets the CBD.
Source: AAP

Breathing in Sydney’s air right now has been compared to smoking the equivalent of 30 cigarettes a day, but health experts say it’s not that simple.

“It’s, as they say, a cause for concern, not alarm,” respiratory physician Professor Guy Marks from the Woolcock Institute of Medical Research, told SBS News.

“The fact is that smoke from tobacco contains certain toxins that have particular health effects that’s not in the smoke from burning biomass or wood, so I’m a little cautious about that equivalence.”

But prolonged exposure can cause respiratory issues and eye irritation, particularly for people with asthma and lung disease.

So what can you do to protect yourself?  

Staying inside with the windows and doors shut is the best way to limit the amount of smoke you’re breathing in. Using an air purifier in a well-sealed house would help filter out any stray particulants.

Short of becoming a hermit and staying inside all of summer, health experts advise taking a common-sense approach when venturing outside.

“This would not be the time to run a marathon, or a half marathon, or intense outdoor exercise,” Professor Marks said.

  Some Sydney-siders have taken to wearing face masks to help cope with the smoke, but the benefits are questionable.

Sydney-siders are concerned about the impact of exposure to bushfire smoke.
Source: AAP

Professor Marks said it depends on which ones you use, declaring surgical masks “completely useless”.

“The sort of simple surgical masks that you often see people wearing that are not very tight fitting that are mainly designed to prevent people from infecting other people, they’re no use and In fact, they may worsen the situation.”

But a P2 mask, also known as a N95 mask, can reduce exposure significantly, filtering out about 95 per cent of the harmful stuff.

For most people though, Associate Professor Lou Irving, a respiratory physician at the Royal Melbourne Hospital and Peter MacCallum Cancer Centre, said it's not necessary.

"For most people, if they don't have chronic lung disease, the wood fire smoke that's lingering over Sydney will be of no harm," he said.

"But there will be days when there is very heavy pollution due to wood fire smoke and more susceptible people such as asthmatics and those with COPD (chronic obstructive pulmonary disease) will be at risk and taking precautions such as wearing a good mask (could help), but a better precaution would be to actually stay indoors." 

Traffic pollution more of a concern

While the bushfire smoke haze may be more noticeable and unpleasant, health experts say we should be more worried about the unseen traffic fumes city residents and workers breath in every day.

"In our society, the more likely cause of chronic exposure to PM2.5 is traffic pollution is diesel pollution," Associate Professor Irving said. 

"Some of the stuff in diesel pollution is much more harmful than what's in bushfire smoke."

Traffic pollution is likely doing more damage to your lungs than bushfire smoke.
Source: AAP

"Although Australia has got, in general, good quality air, we've actually got a very poor approach to diesel pollution compared to Europe and compared to America." 

Diesel contains carcinogens known to cause lung cancer and Australia's fuel standards are not as strict as those in Australia and Europe.  

In 2015, the Australian Institute of Health and Welfare found air pollution caused 3,000 premature deaths in Australia each year. 

Professor Marks agreed Australia should continue to try to reduce air pollution. 

"Any increase is harmful, any decrease is beneficial," he said.

Published 5 December 2019 at 1:20pm, updated 8 December 2019 at 3:30pm
By Rosemary Bolger