Smoke from last summer’s torturous bushfire season likely caused 445 deaths across Australia, says an air pollution expert who today fronted the royal commission into the disaster.

ABC reports Associate Professor Fay Johnston, along with fellow researchers at the Menzies Institute for Medical Research at the University of Tasmania, estimate nearly 80% of all Australians were impacted by the ‘Black Summer’ bushfire smoke.

The thick haze, which dominated Sydney for weeks and reduced visibility in Melbourne, is thought to have caused 3,340 people to seek medical treatment for heart and lung issues.

It’s likely 1,700 people flocked to hospital seeking treatment for asthma-related ailments, the royal commission heard.

On February 4 this year, Prime Minister Scott Morrison said 33 people had died as a direct result of the fires.

Associate Professor Johnson’s statements came on the second day of royal commission hearings, which will investigate Australia’s government response to the fires and “arrangements for improving resilience and adapting to changing climatic conditions.”

That last point is something researchers are very worried about.

As reported by The Daily Telegraph, CSIRO atmospheric scientist Doctor Helen Cleugh told the royal commission it’s very likely that manmade greenhouse gas emissions will skew the climate and worsen future bushfire seasons.

“These dangerous weather conditions for bushfires are likely to occur, at least in part, due to increasing greenhouse gas emissions,” she said.

The royal commission is expected to deliver its final report by August 31.

Image: Dean Lewins / AAP Image