It is a fact that cigarette smoking is the number one factor which can be a causes of lung cancer, research shows way back 1950’s wherein this relationship has been established. A smoke of cigarette contains 4000 harmful chemicals recognized to be causes of lung cancer, one of which is tobacco also contributed in cause of lung cancer, effects of smoking on the person’s body go by far than that of lung cancer. Health effects of smoking in the body effects every organ ranging from life threatening diseases such as cancer, heart related diseases, wrinkles, and also blindness. 
These substances or chemicals are also coined as carcinogens, (cancer-causing agents) and it is said that these carcinogens are the one that causes damage to the cells that are present in the lungs. A cell that has been damaged can mutate and have an abnormal cell production that may proliferate in a long period of time, which then forms tumors that can be at the end, considered cancerous.
One pack of cigarettes per day has 20-25 times the higher risk the smoker on acquiring lung cancer than those who barely smoke or passive smokers, the greater the person smoke the increase in the probability for that person on obtaining lung cancer. In actuality, no one can really tell for sure whether which smoker can have the greater risk of acquiring cancer, but Pipe smoking and Cigar also puts the persons at risk but not more than that of cigarette smokers, because they are more in contact with harmful chemicals in cigarette rather than of that in pipes and cigars, but both puts the person at risk in having lung cancer. The smoker’s chances of obtaining cancer will depend on the following factors such as;
- Person’s age when they began smoking
- The duration of time that the person had smoked
- The number of cigarettes the person take per day
Aside from being an active smoker, there is a term such as passive smokers – these are the people who accidentally or purposely breathe in or inhale someone else’s smoke, this also puts the person at risk of acquiring health hazards such as lung cancer.
Other causes of Lung cancer other than smoking are people who are exposed to chemical and respiratory irritants that can trigger the production of abnormal cells that can be in the long run, turn to be cancerous. The person’s job can be a causes of lung cancer, these includes the overexposure to asbestos, asbestos particles when exposed can stay in the lung tissues damaging the lung cells. It is also due to the exposure of several Industrial chemicals such as coal, nickel chromate, arsenic, vinyl chloride, aromatic hydrocarbons, ethers and organic chemicals such as chloromethyl ethers. Overexposures to radiation can also cause lung cancer due to profession and medical purposes, though this is quite uncommon, it is still considered as a causes of lung cancer. Gas which occurs in natural rocks and soil can release random gas may cause lung cancer. A person with the history of lung cancer is more likely to develop a second lung cancer than that of the person developing the first lung cancer.