What causes lung cancer

The causes of lung cancer are as follows:
• Smoking causes 90% of lung cancer deaths. The chemicals damages the cilia - which are the little hairs in the nostrils and trachea – and stops the trappings of fluids and foreign particles like mucus and dust out of the airway, making them enter the body; breaks down the alveolar walls; and the healthy cells of the lungs are destroyed and replaced by cancer cells. Cigarette or tobacco smoking has 25 times more chance of having lung cancer than non-smokers while pipe or cigar smoking has 5 times more chance of having it than non-smokers.
• Passive smoking which is when non-smokers breathe in the polluted air around smokers.
• Asbestos fibres which used to be found widely in workplaces to make thermal and acoustic insulation.
• Radon gas from the natural chemical that arises from the decay product of Uranium. It travels up through the soil and may enter homes through gaps in the foundation as well as pipes and drains, etc. It is invisible and odourless.
• Lung diseases. When there is a presence of certain diseases in the lung.
• Prior history of lung cancer-survivors of lung cancer can get it a second time.
• Air pollution from vehicles, industry and power plants. This causes 1% of lung cancer deaths.