Quantitative trends in airborne loads of Celtis sinensis pollen and associationswith meteorological variables in a subtropical Australian environment.

Department of Medicine, Woolcock Allergen Unit, Room 461, Blackburn BuildingD06, The University of Sydney, NSW, Australia 2006. brettg@mail.med.usyd.edu.au
Ann Agric Environ Med 2004;11(2):297–302
Celtis sinensis is an introduced plant species to the southeastern regionof Queensland that has had a destructive affect on indigenous plant communities and its pollen has beenidentified as an allergen source. Pollen belonging to C. sinensis was sampled during a 5-year (June 1994-May1999) atmospheric pollen-monitoring programme in Brisbane, Australia, using a Burkard 7-day spore trap.The seasonal incidence of airborne C. sinensis pollen (CsP) in Brisbane occurred over a brief periodeach year during spring (August-September), while peak concentrations were restricted to the beginningof September. Individual CsP seasons were heterogeneous with daily counts within the range 1-10 grainsm(-3) on no more than 60 sampling days; however, smaller airborne concentrations of CsP were recordedout of each season. Correlation co-efficients were significant each year for temperature (p < 0.05),but were less consistent for precipitation (p > 0.05) and relative humidity (p > 0.05). A significantrelationship (r2 =0.81, p=0.036) was established between the total CsP count and pre-seasonal averagemaximum temperature; however, periods of precipitation (> 2 mm) were demonstrated to significantly lowerthe daily concentrations of CsP from the atmosphere. Given the environmental and clinical significanceof CsP and its prevalence in the atmosphere of Brisbane, a clinical population-based study is requiredto further understand the pollen's importance as a seasonal sensitizing source in this region.