What is known to cause cancer in humans….CONTINUE READING
The International Agency for Research on Cancer (IARC)
was created on 20 May 1965, by a resolution of the World Health Assembly, as the specialized cancer agency of the World Health Organization.
According to IARC, one in five people worldwide develop cancer during their lifetime. Today, there are more than 200 types of cancer and they are classified according to where they start in the body, such as breast cancer or lung cancer.
A carcinogen refers to chemicals, combinations of chemicals, or instances of exposure that can cause you to have cancer. The IARC has a system of classification divided into four groups based on the level of evidence indicating their potential to cause cancer,
Below is an infographic that shows the categories used by theIARC Monographs on the Identification of Carcinogenic Hazards to Humansto classify a substance according to the level of certainty that the substance can cause cancer. However, this classification does not indicate the level of risk associated with exposure, also known as carcinogenicity.
According to The International Agency for Research on Cancer:
Group 1 refers to agents that are carcinogenic to humans
This category is used when there is convincing evidence that the agent causes cancer in humans. The evaluation is usually based on the results of epidemiological studies showing the development of cancer in exposed humans. Agents are also classified on the basis of sufficient evidence of carcinogenicity in experimental animals supported by strong evidence in exposed humans that the agent exhibits one or more of the recognized
key characteristics of human carcinogens.
Popular carcinogens that fall under this category include; alcohol, exposure to solar radiation, smoking, and processed meats like salami, hot dogs, and sausages.
NB: Carcinogens which are classified in the same group indicate that substances have a comparable level of evidence for causing cancer. However, the relative risks associated with each substance differ.
Based on findings by Cancer Research UK, annually 34,000 cancer deaths worldwide are caused by diets high in processed meat, while 1 million deaths per year are due to smoking, and 600,000 are due to alcohol consumption.
Group 2A refers to agents which are probably carcinogenic to humans
This category is used when there is positive but not conclusive evidence in humans but either sufficient
evidence of carcinogenicity in experimental animals or strong mechanistic evidence, showing that the
agent exhibits key characteristics of human carcinogens.
Popular carcinogens that fall under this category include; high-temperature frying emission, red meat, DT insecticides, and night shifts.
Group 2B refers to agents that are possibly carcinogenic to humans
This category is generally used when only one of the following evaluations has been made by the Working
Group:
• limited evidence of causing cancer in humans
• sufficient evidence of causing cancer in experimental animals
• strong mechanistic evidence, showing that the agent exhibits key characteristics of human
carcinogens.
Popular carcinogens that fall under this category include; aspartame, engine exhaust fumes, lead, and working as a hairdresser or barber.
Group 3 refers to agents that are not classifiable as to their carcinogenicity to humans
This category is used when both the evidence of carcinogenicity in humans, and experimental animals is limited (or inadequate), and the mechanistic evidence is limited (or inadequate). Limited evidence of carcinogenicity means that the available information suggests a carcinogenic effect but is not conclusive.
Substances that fall under the category include coffee, paracetamol, crude oil, and mercury.
Note that the risk of developing cancer is not solely determined by being exposed to a carcinogen. Several factors like the extent of your exposure to the carcinogen and your genetic makeup also play a significant role in determining the likelihood of having cancer….CONTINUE READING