23 July 2012

A report released today by NSW Health has found that there was no increase in leukaemia or other cancers combined in residents living around the M5 East Tunnel stack.

The report found that it is also unlikely that relatively higher lung cancer rates among these residents were due to emissions from the M5 East Tunnel stack.

The report, A review of cancer registry data in response to concerns about a possible excess of cancer associated with the emissions from the M5 East Tunnel was prepared by the Public Health Units of Sydney and South Eastern Sydney Local Health Districts.

The report was undertaken after concerns were raised by the local community group, Residents Against Polluting Stacks (RAPS).

NSW Health’s independent Air Pollution Expert Advisory Committee, which includes cancer and public health epidemiologist Professor Bruce Armstrong, reviewed early drafts of the report. The Committee required more detailed analysis during the development of the report to ensure all possible scientific explanations were fully explored. Once further analysis was conducted the Committee endorsed the findings.

The final report analysed cancer rates among residents living in an area surrounding the M5 East stack, centred on Turrella, from 6-years before the tunnel opened in December 2001 to 6 years after.  The main health concerns initially expressed by RAPS included leukaemia rates.

Leukaemia rates were not high in this area compared to other areas in NSW and did not increase after the opening of the M5 Tunnel, nor was there any evidence of changes in rates for all cancers combined.

The report found an increase in lung cancer in this area. However, lung cancer generally takes years to develop, and the increase in rates in Turrella was already evident the year after the opening of the tunnel.

In addition, an analysis of longer term trends suggested that the increase may have begun in the mid-1990s.

Monitoring of pollution from the tunnel ventilation stacks suggests that they have contributed very little to the overall levels of air pollution in the area, which are similar to background levels in other parts of Sydney.

Professor Bruce Armstrong, from the Expert Panel on Air Pollution said some forms of air pollution do cause lung cancer.

“This study thoroughly examines whether a local increase in lung cancer could be related to pollution emissions from the M5 East Tunnel,” Professor Armstrong said.

“Most lung cancer is caused by smoking. The most likely explanations for the change in lung cancer rates in the area are changes in rates of smoking in the resident population. Chance may also be a factor, as the cancer rates for a relatively small area will vary quite a lot over time simply by chance.”

Professor Wayne Smith, Director of Environmental Health said the concerns of RAPS and the local community had been taken seriously and its issues investigated thoroughly.

“The Public Health Units of both Sydney Local Health District and South Eastern Sydney Local Health Districts will continue to monitor lung cancer incidence in the Turrella and surrounding areas.”

The report is available at http://www.health.nsw.gov.au/environment/Publications/m5-east-tunnel.pdf [PDF].

For a range of health information, go online to https://www.health.nsw.gov.au.