Exposure Mapping Using Air Quality Modelling

This study explores the development of new techniques able to be applied to a rapidly growing environmental applications area – assessment of exposures and public health effects of ambient air pollution. The technique has been applied as a test case in Auckland, with the implication that it could be further adapted to apply to other cities, both in New Zealand and overseas. The research involved translation of the results of urban airshed modelling into GIS based exposure maps at a census area unit (CAU) scale over the Auckland region. This data was used to identify and compare air pollution spatial patterns for nitrogen dioxide (NO2) and carbon monoxide (CO) for two different exposure periods during 1999 – summer (March) and winter (July). Census data was used at a CAU scale to assess population exposure to air pollution. Population density and degree of socio-economic deprivation were mapped and the existence of spatial relationships or patterns between these various environmental factors was explored. Exposure assessment helped provide probabilistic estimates of the population affected (such as < 5 yr olds and elderly) and the number in the population exposed. The maps generated show relationships between population indicators and air quality indicators, obtained from urban airshed models. Developing these tools and techniques can help provide future health risk estimates