A carcinogen is a something that is known to cause cancer in humans or animals. Carcinogens can be any kind of substance and even if the said substance can promote or worsen cancer without having to actually cause the disease, it is still called carcinogen.
A carcinogen affects a body in the most fundamental level. It can act on the deoxyribonucleic acid – the DNA itself, which causes aberrations or mutations that can lead to the abnormal increase in the growth of cells. The effect on cell division will likely increase the chances of mutations in the DNA. Some carcinogens can also have a bad effect on the body without having to attack or change the DNA.
Carcinogens do not necessarily lead to the development of cancer from every exposure. There are some carcinogens that will only have a detrimental effect if the body is exposed to high levels and for a prolonged period of time. Others, on the other hand, will cause bad effects even with a short period of exposure and at lower levels. The body’s own genetic makeup also plays a factor on how the body will react to a carcinogen.
There are many substances that are already identified as carcinogenic. Among the more common carcinogens are asbestos, some pesticides, arsenic, radon, and tobacco smoke. Actually, even smokeless tobacco is a known carcinogen. The sun itself, which we consider as an essential part of life on earth, can be considered carcinogenic. The ultra violet rays the sun produces is known to cause many types of cancer on the skin.