Understanding Our Smog

"There is a range of compounds that make up airborne pollution and, in Australia, emissions of some of these compounds remain unregulated," says CSIRO's Dr Dennys Angove.

"We will use the smog chamber to investigate a range of synthetic atmospheres comprising naturally occurring hydrocarbons and hydrocarbons from human produced sources

"This will advance our knowledge of the different airborne compounds and how each reacts or changes in the atmosphere. It will also help us understand what happens to the compounds once they have broken down or reacted with the cocktail of chemicals that exist in our air.

"Ultimately, we hope to develop a model that will help regulatory authorities to predict when substances in the air could become harmful to individuals or groups in a specific area. Precautions can then be taken to minimize exposure.

"It will also give atmospheric chemists a greater understanding of how these potentially toxic materials are transported and transformed in the atmosphere.

"The entire area of research into air pollution is now being based around risk assessment. The big question being asked is - how long can you be exposed to something before it harms you?

"The only way to answer this is to know the chemistry of these substances in the atmosphere - a difficult job as they only occur in trace amounts.

"There are other chambers being operated around the world, but the application of new analysis techniques in our chamber will push the science forward significantly."

Dr Angove says, the CSIRO chamber has attracted significant international interest from the United States and Spain where one of Europe's best-known smog chambers is situated.

Last year, at a conference on risk assessment and air pollution in Perth, Australia, it became evident to Dr Angove that there was still considerable conflict among medical experts as to the health impacts of the various components of air pollution.

CSIRO Energy Technology has been studying air pollution for 20 years and has designed and used two smog chambers before the plans for the latest one arose.

"One thing scientists have learnt is that smog is a complex creature that is forcing science to its innovative limits in an effort to understand it," says Dr Angove.

Air pollution occurs in two forms - gases and fine particulates or aerosols. At high enough concentrations, many of the gaseous compounds are recognized as harmful to animals and plants and some, like 1,3-butadiene, are known carcinogens. The aerosols are small enough to enter deep into the lungs and are thought to be one of the factors contributing to lung disease and other human health problems.

The nature of air pollution and the impact it may have depends on a host of factors. These include the pollutant source, reactions in the atmosphere, transport by winds, and removal by clouds, rain, plants and soil.

"Twenty years on we are still trying to understand the complexities of these air toxics. This new chamber will hopefully raise awareness and understanding of just what we are dealing with on a daily basis," says Dr Angove.