Exposure assessment of traffic-related pm10 pollution in outdoor play areas of early childhood centres
This thesis seeks to assess the exposure of children in outdoor play areas of early childhood centres in Auckland City to traffic-related PM10 pollution. An estimated 400 premature deaths occur each year in New Zealand due to motor vehicle emissions. In addition to premature deaths, acute and chronic health effects including asthma, chronic obstructive pulmonary disease (COPD), heart disease and bronchitis, as well as increased hospitalisations and restricted activity days (sick days) are also associated with vehicle emissions. Epidemiological studies have shown that respiratory diseases such as asthma can be exacerbated by increases in the concentration of particulates of less than 10 microns in diameter (PM10) from motor vehicle emissions. Significant positive associations have been found between proximity to heavily travelled roads and increased childhood respiratory disease symptoms including hospitalisations for childhood asthma. In spite of this evidence, many early childhood centres in Auckland are located adjacent to busy roads. Children at these early childhood centres spend much of their time playing in the outdoor areas of these centres with the potential for particulates from motor vehicle emissions to exacerbate symptoms in those children already suffering from respiratory disease and asthma. Very little research has been carried out either in New Zealand or internationally on the air quality of outdoor play areas of early childhood centres in relation to motor vehicle emissions and childhood respiratory disease and asthma. The extent of monitoring is also limited and the amount of exposure data available in New Zealand relatively sparse, particularly in comparison with Europe. Levels of traffic-related PM10 in the outdoor play areas of early childhood centres were measured in centres located adjacent to busy roads and in centres away from a quiet road or adjacent to a very quiet road for comparison. Two of five early childhood centres located alongside busy roads had PM10 levels that exceeded the World Health Organization (WHO) guideline value. While PM10 levels monitored at the other three centres located alongside busy roads did not exceed the WHO guideline value, results were often only marginally within this guideline value. In contrast, PM10 levels monitored at two centres located away from a quiet road and one centre located adjacent to a very quiet road were well within the WHO guideline value. This pilot study provides preliminary evidence that children attending early childhood centres located alongside busy roads have greater exposure to traffic-related PM10 pollution than those attending early childhood centres located away from a quiet road or adjacent to a very quiet road. If the link between PM10 exposure and health effects is causal, as suggested by epidemiological studies, then children attending early childhood centres proximal to busy roads are at a greater risk of respiratory illness than children attending early childhood centres adjacent to quiet roads. Further work is required to confirm the findings in this small sample of air quality around early childhood centres in a larger sample, and possibly to undertake an epidemiological study to confirm the link to health effects. Drawing on the precautionary principle, prudent territorial local authorities should be encouraged to introduce regulations ensuring that any new early childhood centres are located at a specified distance from major roads, and that information for parents, ongoing PM10 monitoring and processes for issuing PM10 advisories when limits are exceeded are available in existing early childhood centres that are adjacent to busy roads.