Ambient air pollution and hospital admissions

Ambient air pollution and daily hospital admissions in Melbourne 1994-1997

Download:

• EPA publication 789 - Ambient Air Pollution and Daily Hospital Admissions in Melbourne 1994-1997 (Adobe PDF file, 475KB)
• appendices (Adobe PDF file, 1376KB or 1.4MB)

The Air Pollution and Health brochure is also available in paper format from EPA's Information Centre. The brochure is a summary of EPA Publication 789.

Air quality continues to be among the top environmental concerns for Victorians. In particular, the community is concerned about the potential impacts of air pollution on their health and quality of life.

Many overseas studies have shown a link between air pollutants, such as particles (PM₁₀ and PM_2.5), ozone, nitrogen dioxide and carbon monoxide (CO), and increases in premature deaths and hospital admissions for people with existing heart and lung disease. These effects have been shown to occur in sensitive groups within the population including the elderly, people with existing illnesses, asthmatics and children. The findings of these studies have focussed attention on air quality standards and the actions required to improve air quality.

In June 2000, EPA Victoria released the Melbourne Mortality Study, the first of a number of collaborative studies with researchers within Australia, investigating the effects of air pollution on the health of Melburnians. The hospital admissions study is a further report investigating these effects.

The hospital admissions study was done in collaboration with researchers from the University of the Sunshine Coast and University of Queensland. The study investigated the association between air pollution and daily emergency admissions for respiratory and cardiovascular disease and asthma. Admissions to all Melbourne hospitals were included in the analysis for the period July 1994 to December 1997. The pollutants studied were fine particles, ozone, nitrogen dioxide and carbon monoxide. The analysis looked at the impact on people across all age groups, with a particular emphasis on the elderly and children.

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Findings of the study

The results of the study show that, after controlling for the effects of weather, all pollutants studied are associated with increases in hospital admissions for respiratory and cardiovascular disease. The effects associated with carbon monoxide, nitrogen dioxide and particles were difficult to separate from each other. This is not surprising given that the main sources of these pollutants are combustion processes such as those used by motor vehicle engines. The effects of ozone were independent of the other pollutants.

Hospital admissions for children with asthma were affected by air pollution, in particular fine particles and ozone. Admissions for the elderly with existing heart disease were strongly associated with carbon monoxide.

The results of this study are consistent with the findings of overseas studies. However, the associations observed between admissions for asthma in children and particles are generally stronger than those observed overseas. This may be due in part to the fact that Australia has the second highest asthma rates in the world.

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Comparison with the Melbourne mortality study

The Melbourne mortality study found that increases in daily mortality were linked with air pollution levels in Melbourne. With the exception of ozone and nitrogen dioxide, the effects of individual pollutants were difficult to separate.

The effects of particles and carbon monoxide were weak compared with the findings of the hospital admissions. However, given that hospital admissions are a more sensitive health indicator, this finding is not surprising.

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