About 80% of cancers are related to the environment

Accordingly, cancer arises due to internal disorders including endocrine disorders, inherited gene damage, also known as causes endogenous. In contrast, cancers arise directly from the living environment, including unscientific lifestyle, bad habits such as smoking, drinking alcohol, unreasonable nutrition. In addition, there are a number of factors due to occupational diseases and environmental pollution, collectively known as exogenous causes (from outside the body).

Exogenous causes can be divided into the following 4 main groups:

Cluster of chemical agents: In this group, smoking is responsible for 30% of all cancers in humans, including lung cancer , larynx, esophagus, oral cavity, bladder, pancreas, stomach. In smoke, in addition to nicotine affecting the cardiovascular system, there are more than 40 different chemicals that cause cancer. Among the various poisons, benzopyrene – a substance capable of causing 100% carcinogenicity in experimental studies. Smokers are 10 to 30 times more likely to develop and die from lung and laryngeal cancer than non-smokers. The younger you smoke, the longer you smoke, the higher the number of cigarettes smoked in a day, the higher the risk.

In Vietnam, smoking water pipes and eating betel nut are also factors that cause lung cancer and oral cavity cancer. If a person smokes and drinks alcohol, the risk of cancer is even higher. Existing smokers who quit smoking have a lower risk of developing cancer over time. After 5 years of stopping smoking, the risk of lung cancer is reduced by 50%, after 10 years of stopping smoking, the risk is no longer significant, almost like a non-smoker. People who do not smoke but live or work in an environment with smokers are also at risk of tobacco-related diseases like smokers themselves, especially for women and children.
 

Risk group due to diet and food hygiene and safety pollution: Diet high in animal fat, low in fiber increases the risk of disease colon cancer – colon and breast cancer. In contrast, a diet low in fat, rich in vegetables, fruits and whole grains, may reduce the risk of various types of cancer.

Food preservatives, food coloring agents of chemical origin, metabolic intermediates and generated from moldy, fermented foods is the cause of many types of gastrointestinal cancers such as stomach cancer, liver cancer, colon cancer… It is estimated that this type of cause causes up to 35% of all cancers.

Smoked meat, salted fish, fish sauces and pickles, salted eggplant, especially cucumbers, which are high in nitrate, nitrite and nitrosamine salts are esophageal carcinogens and stomach.

Rice and peanuts are two foods that are easily infected by mold and secrete a toxin called aflatoxin, which causes primary liver cancer.

In our country, herbicides are also a risk factor for breast cancer and some other cancers. Besides, the consequences of Agent Orange during the war have left heavy consequences not only causing diseases of birth defects but also a potential risk factor for many cancers.

Cancers caused by occupation often occur in direct contact organs such as skin, respiratory system and urinary system, for example, bladder cancer photosensitivity in dyers exposed to aniline in dyes, lung cancer in asbestos mining workers, arsenic-exposed work, blood cancer in people exposed to benzene, laryngeal cancer in people exposed to mustard gas…

Group of physical agents: Including ionizing radiations such as those emitted by X-ray projectors and radioactive substances used in medicine and In some scientific disciplines, it is capable of causing gene damage and cell growth when exposed to irradiation. The effects of radiation on cancer depend on the age of exposure: the younger the age, the more dangerous (especially in the fetus), the greater the dose of exposure, the higher the risk of cancer, and the organs of the body. sensitive to radiation such as thyroid, bone marrow. In addition, ultraviolet rays in sunlight are also a cause of skin cancer.

Group of biological agents: Including some viruses, bacteria. There are three typical viruses associated with cancer: Epstein-Barr virus (EBV) associated with nasopharyngeal cancer, lymphoma. Hepatitis B virus is the cause of primary liver cancer, after entering the body, it will cause acute hepatitis, followed by cirrhosis and liver cancer. The discovery that hepatitis B virus is an important cause of liver cancer has opened an effective way to prevent hepatitis B vaccination against liver cancer. The papillomavirus is a sexually transmitted virus, considered the cause of cervical cancer, very common in Vietnamese women, the disease has a high incidence in women who have early sex. , have many births and have many sexual partners.

In addition, Helicobacter Pylory (HP) bacteria are considered to play an important role in causing stomach ulcers – duodenal and gastric cancer. This is also a fairly common cancer in Vietnam./.