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Unprecedented health costs of smoke-related PM2.5 from the 2019–20 Australian megafires


In flammable landscapes around the globe, longer fire seasons with larger, more severely burnt areas are causing social and economic impacts that are unsustainable. The Australian 2019–20 fire season is emblematic of this trend, burning over 8 million ha of predominately Eucalyptus forests over a six-month period. We calculated the wildfire-smoke-related health burden and costs in Australia for the most recent 20 fire seasons and found that the 2019–20 season was a major anomaly in the recent record, with smoke-related health costs of AU$1.95 billion. These were driven largely by an estimated 429 smoke-related premature deaths in addition to 3,230 hospital admissions for cardiovascular and respiratory disorders and 1,523 emergency attendances for asthma. The total cost was well above the next highest estimate of AU$566 million in 2002–03 and more than nine times the median annual wildfire associated costs for the previous 19 years of AU$211 million. There are substantial economic costs attributable to wildfire smoke and the potential for dramatic increases in this burden as the frequency and intensity of wildfires increase with a hotter climate.

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Fig. 1: Geographic context of the analysis of health costs associated with smoke from the Australian 2019–20 fires.
Fig. 2: Smoke-related health costs for Australian fire seasons (1 October to 31 March) between 2000 and 2020.
Fig. 3: Annual smoke-related health costs.

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Data availability

The data that support the findings of this study are available on request from the corresponding author on a case-by-case basis. Source data are provided with this paper.

Code availability

The custom code generated during the current study is available from the corresponding author on a case-by-case basis.


  1. Bowman, D. M. et al. Human exposure and sensitivity to globally extreme wildfire events. Nat. Ecol. Evol. 1, 0058 (2017).

    Article  Google Scholar 

  2. Abatzoglou, J. T. & Williams, A. P. Impact of anthropogenic climate change on wildfire across western US forests. Proc. Natl Acad. Sci. USA 113, 11770–11775 (2016).

    Article  CAS  Google Scholar 

  3. National Indicative Aggregated Fire Extent Dataset 2020 (Australian Government Department of Agriculture Water and the Environment, 2020);

  4. Nolan, R. H. et al. Causes and consequences of eastern Australia’s 2019–20 season of mega‐fires. Glob. Change Biol. 26, 1039–1041 (2020).

    Article  Google Scholar 

  5. van Oldenborgh, G. J. et al. Attribution of the Australian bushfire risk to anthropogenic climate change. Nat. Hazard. Earth Syst. Sci. Discuss. (2020).

  6. McWethy, D. B. et al. Rethinking resilience to wildfire. Nat. Sustain. 2, 797–804 (2019).

    Article  Google Scholar 

  7. Bowman, D. M., O’Brien, J. A. & Goldammer, J. G. Pyrogeography and the global quest for sustainable fire management. Annu. Rev. Environ. Resour. 38, 57–80 (2013).

    Article  Google Scholar 

  8. Reid, C. et al. Critical review of health impacts of wildfire smoke exposure. Environ. Health Perspect. 142, 1334–1343 (2016).

    Article  Google Scholar 

  9. Williamson, G. J. et al. A transdisciplinary approach to understanding the health effects of wildfire and prescribed fire smoke regimes. Environ. Res. Lett. 11, 125009 (2016).

    Article  CAS  Google Scholar 

  10. Fann, N. et al. The health impacts and economic value of wildland fire episodes in the US: 2008–2012. Sci. Total Environ. 610, 802–809 (2018).

    Article  CAS  Google Scholar 

  11. Cascio, W. E. Wildland fire smoke and human health. Sci. Total Environ. 624, 586–595 (2018).

    Article  CAS  Google Scholar 

  12. Doubleday, A. et al. Mortality associated with wildfire smoke exposure in Washington state, 2006-2017: a case-crossover study. Environ. Health 19, 4 (2020).

    Article  Google Scholar 

  13. Lipner, E. M. et al. The associations between clinical respiratory outcomes and ambient wildfire smoke exposure among pediatric asthma patients at National Jewish Health, 2012–2015. GeoHealth 3, 146–159 (2019).

    Article  Google Scholar 

  14. Gan, R. W. et al. Comparison of wildfire smoke estimation methods and associations with cardiopulmonary-related hospital admissions. GeoHealth 1, 122–136 (2017).

    Article  Google Scholar 

  15. Lassman, W. et al. Spatial and temporal estimates of population exposure to wildfire smoke during the Washington state 2012 wildfire season using blended model, satellite, and in situ data. GeoHealth 1, 106–121 (2017).

    Article  Google Scholar 

  16. Thomas, D. et al. The Costs and Losses of Wildfires: A Literature Review (US Department of Commerce, National Institute of Standards and Technology, 2017).

  17. Ashe, B., McAneney, K. J. & Pitman, A. J. Total cost of fire in Australia. J. Risk Res. 12, 121–136 (2009).

    Article  Google Scholar 

  18. Stephenson, C. A Literature Review on the Economic, Social and Environmental Impacts of Severe Bushfires in South-eastern Australia (Victorian Government Department of Sustainability and Environment, 2010).

  19. Ladds, M. et al. How much do disasters cost? A comparison of disaster cost estimates in Australia. Int. J. Disaster Risk Reduct. 21, 419–429 (2017).

    Article  Google Scholar 

  20. Borchers Arriagada, N. et al. Exceedances of national air quality standards for particulate matter in Western Australia: sources and health-related impacts. Med. J. Aust. (2020).

  21. Borchers Arriagada, N. et al. Unprecedented smoke-related health burden associated with the 2019–20 bushfires in eastern Australia. Med. J. Aust. (2020).

  22. Bowman, D. et al. Human-environmental drivers and impacts of the globally extreme 2017 Chilean fires. AMBIO 48, 350–362 (2019).

    Article  Google Scholar 

  23. Broome, R. A. et al. A rapid assessment of the impact of hazard reduction burning around Sydney, May 2016. Med. J. Aust. 205, 407–408 (2016).

    Article  Google Scholar 

  24. Horsley, J. A. et al. Health burden associated with fire smoke in Sydney, 2001–2013. Med. J. Aust. 208, 309–310 (2018).

    Article  Google Scholar 

  25. Kochi, I. et al. Valuing mortality impacts of smoke exposure from major Southern California wildfires. J. For. Econ. 18, 61–75 (2012).

    Google Scholar 

  26. Héroux, M.-E. et al. Quantifying the health impacts of ambient air pollutants: recommendations of a WHO/Europe project. Int. J. Public Health 60, 619–627 (2015).

    Article  Google Scholar 

  27. Matz, C. J. et al. Health impact analysis of PM2.5 from wildfire smoke in Canada (2013–2015, 2017–2018). Sci. Total Environ. 725, 138506 (2020).

    Article  CAS  Google Scholar 

  28. Borchers-Arriagada, N. et al. Association between fire smoke fine particulate matter and asthma-related outcomes: systematic review and meta-analysis. Environ. Res. 179, 108777 (2019).

    Article  CAS  Google Scholar 

  29. Thomas, D. Why do estimates of the acute and chronic effects of air pollution on mortality differ? J. Toxicol. Environ. Health A 68, 1167–1174 (2005).

    Article  CAS  Google Scholar 

  30. Limaye, V. S. et al. Estimating the health‐related costs of 10 climate‐sensitive US events during 2012. GeoHealth 3, 245–265 (2019).

    Article  Google Scholar 

  31. Kochi, I. et al. Valuing morbidity effects of wildfire smoke exposure from the 2007 Southern California wildfires. J. For. Econ. 25, 29–54 (2016).

    Google Scholar 

  32. Black, C. et al. Wildfire smoke exposure and human health: significant gaps in research for a growing public health issue. Environ. Toxicol. Pharmacol. 55, 186–195 (2017).

    Article  CAS  Google Scholar 

  33. Obradovich, N. et al. Empirical evidence of mental health risks posed by climate change. Proc. Natl Acad. Sci. USA 115, 10953–10958 (2018).

    Article  CAS  Google Scholar 

  34. Marlier, M. E. et al. Fire emissions and regional air quality impacts from fires in oil palm, timber, and logging concessions in Indonesia. Environ. Res. Lett. 10, 085005 (2015).

    Article  CAS  Google Scholar 

  35. From Smoke Going Round the World to Aerosol Levels, NASA Observes Australia’s Bushfires 2020 (NASA, 2020);

  36. Bowman, D. M. et al. Can air quality management drive sustainable fuels management at the temperate wildland–urban interface? Fire 1, 27 (2018).

    Article  Google Scholar 

  37. Search For and Download Air Quality Data 2020 (NSW Department of Planning Industry & Environment, 2020);

  38. Download Air Data 2020 (Queensland Government, 2020);

  39. Air Quality Monitoring Data 2020 (ACT Government, 2020);

  40. EPA AirWatch 2020 (EPA Victoria, 2020);

  41. Access Historical BLANkET Data 2020 (EPA Tasmania, 2020);

  42. Air Quality Data 2020 (Government of Western Australia, Department of Water and Environmental Regulations, 2020);

  43. Air Quality Monitoring Results (EPA South Australia, 2020);

  44. Xie, X. et al. A review of urban air pollution monitoring and exposure assessment methods. ISPRS Int. J. Geoinf. 6, 389 (2017).

    Article  Google Scholar 

  45. Wong, D. W., Yuan, L. & Perlin, S. A. Comparison of spatial interpolation methods for the estimation of air quality data. J. Expo. Anal. Environ. Epidemiol. 14, 404–415 (2004).

    Article  CAS  Google Scholar 

  46. Johnston, F. H. et al. Creating an integrated historical record of extreme bushfire smoke events in Australian cities from 1994 to 2007. J. Air Waste Manage. Assoc. 61, 390–398 (2011).

    Article  CAS  Google Scholar 

  47. Martin, K. L. et al. Air pollution from bushfires and their association with hospital admissions in Sydney, Newcastle and Wollongong, Australia 1994–2007. Aust. N. Z. J. Public Health 37, 238–243 (2013).

    Article  Google Scholar 

  48. Johnston, F. H. et al. Extreme air pollution events from bushfires and dust storms and their association with mortality in Sydney, Australia 1994–2007. Environ. Res. 111, 811–816 (2011).

    Article  CAS  Google Scholar 

  49. Morgan, G. et al. The effects of bushfire smoke on daily mortality and hospital admissions in Sydney, Australia, 1994 to 2002. Epidemiology 21, 47–55 (2010).

    Article  Google Scholar 

  50. National Environment Protection (Ambient Air Quality) Measure Annual Reporting 2019 (National Environment Protection Council, 2020);

  51. Deaths, Year of Occurrence, Age at Death, Age-Specific Death Rates, Sex, States, Territories and Australia (Australian Bureau of Statistics, 2018).

  52. ERP by SA2 (ASGS 2016), Age and Sex, 2001 Onwards (Australian Bureau of Statistics, 2018).

  53. Emergency Department Care 2014–15: Australian Hospital Statistics Health Services Series No. 65, Cat. No. HSE 168 (Australian Institute of Health and Welfare, 2015).

  54. Emergency Department Care 2015–16: Australian Hospital Statistics Health Services Series No. 72, Cat. No. HSE 182 (Australian Institute of Health and Welfare, 2016).

  55. Aboriginal and Torres Strait Islander Health Performance Framework (Australian Institute of Health and Welfare, 2017).

  56. Emergency Department Care 2016–17: Australian Hospital Statistics Health Services Series No. 80, Cat. No. HSE 194 (Australian Institute of Health and Welfare, 2017).

  57. Centre for Epidemiology and Evidence Health Statistics New South Wales (NSW Ministry of Health, accessed 15 December 2019);

  58. Izquierdo, R. et al. Health impact assessment by the implementation of Madrid City air-quality plan in 2020. Environ. Res. 183, 109021 (2020).

    Article  CAS  Google Scholar 

  59. Lehtomaki, H. et al. Health impacts of ambient air pollution in Finland. Int. J. Environ. Res. Public Health 15, 736 (2018).

    Article  CAS  Google Scholar 

  60. Burnett, R. T. et al. An integrated risk function for estimating the global burden of disease attributable to ambient fine particulate matter exposure. Environ. Health Perspect. 122, 397–403 (2014).

    Article  Google Scholar 

  61. Chen, C. et al. Short-term exposures to PM2.5 and cause-specific mortality of cardiovascular health in China. Environ. Res. 161, 188–194 (2018).

    Article  CAS  Google Scholar 

  62. Bell, M. L. & Davis, D. L. Reassessment of the lethal London fog of 1952: novel indicators of acute and chronic consequences of acute exposure to air pollution. Environ. Health Perspect. 109, 389–394 (2001).

    CAS  Google Scholar 

  63. Sastry, N. Forest fires, air pollution, and mortality in southeast Asia. Demography 39, 1–23 (2002).

    Article  Google Scholar 

  64. National Hospital Cost Data Collection, Public Hospitals Cost Report, Round 20 (Financial Year 2015–16) (Independent Hospital Pricing Authority, 2018);

  65. Average Weekly Earnings, Australia, May 2018 (Australian Bureau of Statistics, 2018);

  66. Labour Force, Australia, October 2018 (Australian Bureau of Statistics, 2018).

  67. Emergency Care Costing and Classification Project: Cost Report (Health Policy Analysis, Independent Hospital Pricing Authority, 2017).

  68. Best Practice Regulation Note—Value of Statistical Life (Australian Government Office of Best Practice Regulation, 2014);

  69. The Economic Consequences of Outdoor Air Pollution (OECD Publishing, 2016);

  70. Robinson, L. A., Hammitt, J. K. & O’Keeffe, L. Valuing mortality risk reductions in global benefit–cost analysis. J. Benefit Cost Anal. 10, 15–50 (2019).

    Article  Google Scholar 

  71. Kelly, F. J. & Fussell, J. C. Air pollution and public health: emerging hazards and improved understanding of risk. Environ. Geochem. Health 37, 631–649 (2015).

    Article  CAS  Google Scholar 

  72. Laden, F. et al. Reduction in fine particulate air pollution and mortality: extended follow-up of the Harvard Six Cities study. Am. J. Respir. Crit. Care Med. 173, 667–672 (2006).

    Article  CAS  Google Scholar 

  73. Inflation Calculator 2020 (Reserve Bank of Australia, 2020);

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We thank the Environment Protection Authority of Victoria, Tasmania and South Australia; the Department of Environment in Queensland; the Department of Infrastructure Planning and Environment of New South Wales; and the Department of Water and Environmental Regulation of Western Australia for providing the available hourly and daily air quality data since 2000. We thank the New South Wales government’s Department of Planning, Industry & Environment for providing funds to support this research via the Bushfire Risk Management Research Hub. N.B.-A. is supported by a Tasmania Graduate Research Scholarship, by Asthma Australia through a Top-up Scholarship and by the New South Wales Bushfire Risk Management Research Hub through a Top-up Scholarship.

Author information

Authors and Affiliations



F.H.J. and D.M.J.S.B. conceived the paper. F.H.J. drafted the manuscript. N.B.-A. conducted the analyses and contributed to the design, methods and paper. G.G.M., B.J. and A.J.P. contributed to the methodological approach and the paper. G.J.W. and D.M.J.S.B. contributed to the methods, the fire data and writing the paper.

Corresponding author

Correspondence to Fay H. Johnston.

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Extended data

Extended Data Fig. 1 Population-weighted daily PM2.5 statistic (μg/m3) by State for the 2019/2020 fire season and the median of the previous 19 fire seasons.

Vertical lines mark the 25th, 50th, 75th and 95th centiles. The interquartile range is shaded. Exposure data available from: 2012 for ACT, 2010 for TAS, 2001 for SA, 2000 for all other states.

Source data

Extended Data Fig. 2 Median population-weighted PM2.5 (μg/m3) by State and fire season.

Exposure data available from: 2012 for ACT, 2010 for TAS, 2001 for SA, 2000 for all other states.

Source data

Extended Data Fig. 3 Magnitude and costs of premature mortality estimated using risk coefficients for short term exposure, long term exposure, and by calculating the years of life lost.

Exposure data and associated costs available from: 2012 for ACT, 2010 for TAS, 2001 for SA, 2000 for all other states.

Extended Data Fig. 4 Sensitivity analysis showing the influence of constraining the maximum daily PM2.5 concentrations on the estimated health burden.

Results shown for the 2019–20 fire season and the median of the previous 19 fire seasons.

Extended Data Fig. 5 Total costs ($AUD million) across different fire identification criteria.

Sensitivity analysis showing the influence of selecting different cut-points for identifying a wildfire smoke affected day on the total estimated health related costs by fire season. (Costs in AUD Mil).

Extended Data Fig. 6 Estimated health costs ($AUD million) for each fire season by State and Territory of Australia.

Results for main analysis. Exposure data and associated costs available from: 2012 for ACT, 2010 for TAS, 2001 for SA, 2000 for all other states.

Supplementary information

Supplementary Information

Supplementary Tables 1–13 and Methods.

Source data

Source Data Fig. 2

Cumulative health costs (main analysis) for each fire season and day of fire season (1 October is Day 1).

Source Data Fig. 3

Estimated health costs ($AUD million) by state and fire season.

Source Data Extended Data Fig. 1

Daily population-weighted PM2.5 by state, date and fire season.

Source Data Extended Data Fig. 2

Population-weighted PM2.5 average by fire season for each state and all states included in study.

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Johnston, F.H., Borchers-Arriagada, N., Morgan, G.G. et al. Unprecedented health costs of smoke-related PM2.5 from the 2019–20 Australian megafires. Nat Sustain 4, 42–47 (2021).

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