Impact of exposure to mine fire emitted PM2.5 on ambulance attendances: A time series analysis from the Hazelwood Health Study

Caroline X Gao; Christina Dimitriadis; Jillian Ikin; Joanna F Dipnall; Rory Wolfe; Malcolm R Sim; Karen Smith; Martin Cope; Michael J Abramson; Yuming Guo

doi:10.1016/j.envres.2020.110402

Impact of exposure to mine fire emitted PM_2.5 on ambulance attendances: A time series analysis from the Hazelwood Health Study

Environ Res. 2021 May:196:110402. doi: 10.1016/j.envres.2020.110402. Epub 2020 Oct 31.

Authors

Affiliations

¹ Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia; Centre for Youth Mental Health (Orygen), University of Melbourne, Australia.
² Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.
³ Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia; School of Medicine, Deakin University, Geelong, Victoria, Australia.
⁴ Ambulance Victoria, Doncaster, Australia.
⁵ CSIRO Oceans and Atmosphere, Aspendale, Victoria, Australia.
⁶ Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia. Electronic address: yuming.guo@monash.edu.

PMID: 33137314
DOI: 10.1016/j.envres.2020.110402

Abstract

Background: For six weeks from February 9, 2014, smoke and ash from a fire in the Morwell open cut brown coal mine adjacent to the Hazelwood power station covered parts of the Latrobe Valley, in south eastern Australia.

Aims: To evaluate the health impact of the mine fire, daily counts of ambulance attendances from July 2010 to March 2015 were analysed.

Methods: Time series models were used to evaluate the relative risk of ambulance attendances during the mine fire, in comparison with the remainder of the analysis period, and to also assess the risk of ambulance attendances associated with lagged effects of exposure to mine fire-related PM_2.5 levels. The models controlled for factors likely to influence ambulance attendances including seasonality, long-term temporal trends, day of the week, daily maximum temperature and public holidays.

Results: A 10 μg/m³ increase in fire-related PM_2.5 was found to be associated with a 42% (95%CI: 14-76%) increase in ambulance attendances for respiratory conditions and a 7% (0-14%) increase in all ambulance attendances over a 20-day lag period. A smaller effect associated with exposure to fire-related PM_2.5 was identified when assuming shorter lag effects. Similar results were identified when assessing whether ambulance attendances increased during the 30-day mine fire period. There was a 15% (8-21%) increased risk of ambulance attendances for all conditions and a 47% (19-81%) increased risk for respiratory conditions during the mine fire period.

Conclusions: Exposure to smoke and ash from a fire in an open cut brown coal mine was associated with increased ambulance attendances, particularly for respiratory conditions. These findings guide the development and implementation of effective and timely strategies and health service planning to respond and mitigate health risks that arise in affected communities during future major air pollution episodes.

Keywords: Ambulance attendances; Coalmine fire; Fire smoke exposure; PM(2.5); Respiratory conditions.

MeSH terms

Air Pollutants* / analysis
Air Pollutants* / toxicity
Air Pollution* / analysis
Air Pollution* / statistics & numerical data
Ambulances / statistics & numerical data
Occupational Exposure / statistics & numerical data
Particulate Matter / analysis
Particulate Matter / toxicity
South Australia

Substances

Air Pollutants
Particulate Matter