Many believed that the emission in Sydney's M5 East tunnel have caused cancer among the residence of Turrella. However, it was found later that smoking habit is the main culprit behind causing cancer especially lung cancer.

The Sydney's M5 East tunnel was opened in 2001. Since then, a large number of cancer cases have been reported. People believed that the emission of the tunnel might have caused cancer to them. But, they failed to understand the risk imposed by the cigarette smoke.

Previous studies have strongly linked cigarette smoke to lung cancer. While commenting upon the increased cancer cases in the region Professor Bruce Armstrong from the Expert Panel on Air Pollution noted that increased instances of smoking have led to increased cases of cancer.

Before the opening of the tunnel, the residents of Turrella had had significant cases of lung cancer. There is least probability of emission of having triggered the number of cancer cases in the region, believe pollution experts. Efforts are required to put towards limiting the smoking habits of the people. It has further come to light that the cases of leukemia have also increased significantly in the past few years.