Black summer bushfires of 2019-20 led to huge health burden in NSW, study finds

Monash University

On 14 January 2020, the level of potentially deadly particulate matter in the NSW bushfires was recorded at 14 times higher than the previous record. Today data is published from the first comprehensive study of the health effects following the catastrophic New South Wales (NSW) bushfires of 2019-20 has found a significant increase in emergency department visits for respiratory and cardiovascular problems, with the authors warning that climate change necessitates increased strategies preventing bushfires because of short and long term health implications.

The study, led by Professor Yuming Guo, from the Monash University School of Public Health and Preventive Medicine and published in the journal, Science of the Total Environment, look at all emergency department (ED) visits across all the NSW in the bushfire seasons (December to February) from 2017 to 2020.

The number of presentations to EDs in fire and non-fire affected regions, as determined by fire density data from NASA satellites, was compared across the three fire seasons of the study. In total, the researchers looked at more than 416,000 ED attendances over the study period.

The researchers found that the 2019-20 fire season had six per cent more weekly ED presentations for respiratory disease and 10 per cent increased cardiovascular presentations compared to the previous two fire seasons, mainly and not unexpectedly in high fire regions, but also impacting lower socio-economic areas the most, according to Professor Guo. “The 2019-20 bushfires in Australia were more intense and started much earlier than in previous years, driven largely by severe drought and an increase in extremely hot temperatures,” he said. These Black Summer fires, as they were known, extended along the Eastern coast burning 19.4 million hectares of land and killing 34 people.

The study conducted by the Monash researchers is the first to look at the health impacts of a severe fire season, though this group and others have looked at the health impacts of wildfire smoke globally, in particular the harmful effects of fine and coarse particulate matter in wildfire or bushfire smoke.

In Australia, during the 2019-20 season, the density of particulate matter in the air peaked on 14 January at fourteen times more than the historically highest level previously recorded. According to Professor Guo, it is known that PM1.0, PM 2.5 – the two most common particle-sized matter in smoke – can cause respiratory disease, chronic obstructive disease, pulmonary disease and asthma, “however this is the first study to look at the impact of bushfires on actual ED attendance numbers.”

“The results indicate that the unprecedented bushfires led to a huge health burden, showing a higher risk in regions with lower socio-economic areas and more bushfires. This study could help to develop more targeted policies and strategies to prevent adverse effects and recover from the disaster, especially in the context of climate change and the COVID-19 pandemic,” Professor Guo said.

/Public Release.