Bushfire smoke and the relationship between human and landscape health

Researchers: Dr DM Bowman, Dr OF Price, Dr JL Gras, Dr M Foley, Dr FH Johnston, A/Prof RS Bailie, A/Prof DL Parry, Prof L Pilotto, Dr SG Haberle, Dr J Stevenson.

Linkage Partners: Northern Territory University, NT Department of Business, Industry and Resource Development, Department of Infrastructure Planning and Environment, Department of Health and Community Services, and Bureau of Meteorology.

Summary: A team of landscape ecologists, palynologists, environmental chemists and public health specialists will determine the ecological causes and adverse health effects of different levels of bushfire smoke in Darwin. Darwin is an ideal setting for this research because the only source of air pollution is the high incidence of controlled and uncontrolled bushfires during the dry season causing variable air quality: a preliminary study found a link between smoke pollution levels and asthma. The findings of the proposed research will contribute to improved fire management practices to reduce injurious smoke pollution events and contribute to setting appropriate national air quality standards

Results

• Two stations (suburbs of Casuarina and Palmerston) show broadly similar seasonal trends in daily pollen concentrations => regional signal
  
  
• Peak in herbaceous pollen taxa (grasses and sedges) and wattles occurs at the onset of the dry season
  
  
• The peak in woody pollen taxa (Callitris and Eucalyptus) occurs at the onset of the wet season

This study has produced the first continuously measured pollen data for Darwin and tropical Australia. It has demonstrated that 70% of the yearly pollen load occurs during the dry season, with the peak loads of common allergy causing pollen occurring in the first two months of the dry season. The study has also demonstrated that these taxa, such as the grasses, have predictable seasonal occurrences, a finding that is important for respiratory health management in the area. Most of the native tree taxa appear to have predictable peak pollen periods, however the actual loads can very considerably from one year to the other. The Myrtaceae family proved to be the least predictable, but this large umbrella category has captured an array of habitat types that respond in different ways to changing meteorological conditions. Continued monitoring will provide a more substantial dataset suitable for statistical analyses focused untangling the processes behind seasonal variation in Darwin’s pollen signature. This future work will ultimately lead to a predictive model of pollen loads for the Darwin region, an important tool for managing respiratory health.

Publications from projects so far:

Stevenson, J., Haberle, S.G., Johnston, F.H., and Bowman, D.M.J.S. (2007) Seasonal distribution of pollen in the atmosphere of Darwin, tropical Australia: Preliminary results. Grana 46, 34-42. [0.5Mb]

Hanigan, I.C., Johnston, F. H. (2007) Respiratory hospital admissions were associated with ambient airborne pollen in Darwin, Australia, 2004–2005. Clinical & Experimental Allergy 37, 1556–1565.