Charles Darwin University

CDU eSpace
Institutional Repository

 
CDU Staff and Student only
 

Health effects of bushfire smoke in the Australian monsoon tropics

Johnston, Fay H. (2008). Health effects of bushfire smoke in the Australian monsoon tropics. PhD Thesis, Charles Darwin University.

Document type: Thesis
Citation counts: Google Scholar Search Google Scholar
Attached Files (Some files may be inaccessible until you login with your CDU eSpace credentials)
Name Description MIMEType Size Downloads
Download this reading Thesis_CDU_8316_Johnston_F.pdf PDF version generated by Student application/pdf 3.89MB 13
Reading the attached file works best in Firefox, Chrome and IE 9 or later.

Author Johnston, Fay H.
Title Health effects of bushfire smoke in the Australian monsoon tropics
Institution Charles Darwin University
Publication Date 2008-07-10
Thesis Type PhD
Supervisor Bailie, Ross S.
Pilotto, Louis
Subjects 1199 - Other Medical and Health Sciences
0599 - Other Environmental Sciences
Abstract Introduction
There is increasing scientific consensus about the adverse health effects of outdoor particulate air pollution. Most evidence has come from studies set in large urban centres where airborne particulate matter is primarily derived from fossil fuel combustion by industrial plants and motor vehicles. The impact of ambient pollution originating from biomass combustion, particularly vegetation or forest fires, is less certain. Despite this uncertainty, land managers in Australia and overseas are increasingly required to meet strict air quality targets in their planned fuel reduction burns and address criticism from communities affected by fire disasters about the adequacy of these preventive operations. This thesis contributes to the evidence-base about the health effects of biomass smoke, particularly at the lower levels that occur in Darwin, northern Australia where approximately 95% of outdoor particulate matter comes from low-intensity seasonal vegetation fires.

Methods
I conducted a prospective panel study of the relationship between daily fluctuations in atmospheric particulate matter and daily symptoms, medication use and heath care attendances in a cohort of people with asthma. I also conducted case-crossover and timeseries studies of daily levels of particulate matter and hospital admissions for respiratory and cardiovascular conditions, and a case-crossover study of emergency department attendances.

Results
Particulate loadings generally remained low with a mean of PM10 of 18 μg/m3 over the dry seasons of 2000, 2004 and 2005 and a mean PM2.5 of 10 μg/m3 over the dry seasons of 2004 and 2005. In the panel study, both PM10 and PM2.5 were positively associated with the proportion of people with asthma experiencing symptoms and commencing steroid tablets. In the time-series and case-crossover studies, PM10 showed borderline positive associations with respiratory conditions in non-Indigenous people and significant positive associations in iv Indigenous people. There were mostly inverse or absent associations for cardiovascular admissions. While no associations were found between either PM10 or PM2.5 and emergency department attendances, the available data for this outcome were limited and the study lacked adequate statistical power.

Conclusions
Adverse health respiratory outcomes were measurable at particulate pollution levels well below Australia’s current air quality standards. Managers of deliberate burns, the primary intervention for preventing severe wildfires, therefore need to manage the health risks associated with smoke from these fires. While these risks might be justifiable when compared with the many harms associated with uncontrolled fires and extreme pollution episodes, it is important that the amount of smoke affecting urban areas is minimised, the impact on air quality in urban areas is evaluated and that advance public advisories are provided to allow people at higher risk from exposure to smoke to take appropriate action.


© copyright

Every reasonable effort has been made to ensure that permission has been obtained for items included in CDU eSpace. If you believe that your rights have been infringed by this repository, please contact digitisation@cdu.edu.au.

 
Versions
Version Filter Type
Access Statistics: 30 Abstract Views, 13 File Downloads  -  Detailed Statistics
Created: Fri, 12 Feb 2010, 21:04:36 CST by Iwona Rohoza