This purpose of this project is to assess the comparative risk associated with exposure to traffic pollution when travelling via different transport modes in New Zealand cities. Concentrations of the key traffic-related pollutants (particulate matter: (PM): PM10, PM2.5, PM1; ultrafine particles (UFPs) and carbon monoxide (CO)) were simultaneously monitored on pre-defined routes in Auckland and Christchurch during the morning and evening commute on people travelling by car, bus, on-road bike, train (Auckland only) and off-road bike (Christchurch only) from February to May 2009.
The key results of this research are:
• Car drivers are consistently exposed to the highest average levels of CO.
• On-road cyclists are exposed to higher levels of CO, PM1 and UFPs than off-road cyclists.
• Car drivers and bus passengers are exposed to higher average levels of UFP than cyclists.
• At some parts of their journeys, travellers are exposed to very high levels of pollution, often for short periods of time.
• Locating cycle paths just a short distance from roads can reduce pollution exposure significantly.
• One hour of commuting could contribute up to 20% of total daily CO and UFP.
• PM10 and PM2.5 are inappropriate indicators of exposure to vehicle emissions.