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• Carcinogen

In 90% of cases, gene mutation is not inherited but due to exposure to one or more carcinogens in the environment during our lifetime. The damage done to the cells is permanent. Over time, as cells suffer greater exposure to carcinogens, the damage adds up, causing a greater chance for cancer to develop.

Carcinogens are cancer-causing agents that have the ability to cause DNA inside a cell to undergo mutation. The damage done to the cells is permanent and adds up over time as cells suffer greater exposure to carcinogens. This results in a greater chance of developing cancer.

Carcinogens can be physical, chemical or biological factors. The diagram below shows some of the common carcinogens.

Ultraviolet Radiation
Excessive exposure to the sun's ultraviolet rays is the main cause of skin cancer. Skin cancer occurs most often in those who are fair-skinned, have light-colored hair and blue or green eyes.

Ionising Radiation
Ionising radiation is a potent carcinogen associated in particular with leukaemia (cancer of the blood) and skin cancer. The degree of seriousness of its effects depends on the type of radiation, ranging from the dangerous nuclear radiation to relatively harmless, such as low-level emissions from certain fertilizers and building materials, and X-rays.