The following is a basic over view of the classifications used in determining the different types of carcinogens:

Chemical:
These can be any number of substances, including but not limited to caustic chemicals, asbestos, gases, and the most dangerous yet controllable cause-tobacco smoke.

Your work environment may be to blame; thankfully the government has gotten much stricter about employee exposure to toxins in the last two decades.

Please report any and all infractions you see on the job site, it could save not only your life but the lives of your fellow workers.

STOP SMOKING, this is a completely controllable cancer causing agent. Find the help you need to quit, if not for you-do it for your kids.

Physical:
An example would be radiation, such UV rays from the sun, microwaves, high power lines, and x-ray overexposure.

Using the appropriate sun block will put the odds in your favor. Remember to reapply every two hour. You also should reapply if you get wet from sweat or swimming, even if it state that it is water proof.

While proof is hard to come by, the number of people that live under power lines contract cancer at a disproportionate rate. My Aunt was one of them.

Heredity:
If you have a family history of cancer, especially women, you need to make the necessary lifestyle changes to combat the disease before it rears it ugly head.

Breast cancer is often found in several generations of women, please get your mammograms as often as your doctor requires.

Biological:
These include but are not limited to: infections by virus (Hepatitis B Virus and liver cancer, Human Papilloma Virus (HPV) and cervical cancer) and bacteria (Helicobater pylori and gastric cancer) and parasites (schistosomiasis and bladder cancer) contamination of food by mycotoxins such as aflatoxins (products of Aspergillus fungi) causing liver cancer.

Any one of the four these different carcinogen factors listed above can bring about cancer in many parts of your body. Some of the most common areas are the lung, larynx, esophagus, stomach, bladder, ovaries, testicles, and mouth.

Conclusion:
I fear that the hormones and preservatives that are so prevalent in food today have a huge impact on the carcinogen levels we intake everyday.

While you have probably heard this a million times before, it bears repeating; if you can not pronounce the ingredients in your food, it is probably not good for you.

In my opinion, your best bet is to eat as many organic or at least chemical free foods as you can, start an exercise program immediately, and alleviate any controllable (Smoking, asbestos in your home, etc.) carcinogens in your day to day life.