Carcinogenität

Carcinogenicity refers to the ability of a substance or agent to cause cancer. Cancer is a disease characterized by uncontrolled cell growth and the potential to invade or spread to other parts of the body. Carcinogens can be physical agents, chemical substances, or biological agents.

Physical carcinogens include ionizing radiation, such as X-rays and gamma rays, and ultraviolet (UV) radiation from sunlight. These agents can damage DNA, leading to mutations that can initiate cancer development. Chemical carcinogens are a diverse group of compounds. Examples include certain components of tobacco smoke, asbestos fibers, and some industrial chemicals. These substances can directly interact with DNA, modify it, or interfere with cellular processes that repair DNA damage. Biological carcinogens include certain viruses, such as the human papillomavirus (HPV) which is linked to cervical cancer, and hepatitis B and C viruses, associated with liver cancer. Bacteria, like Helicobacter pylori, can also contribute to cancer development, particularly stomach cancer.

The process by which a carcinogen causes cancer is complex and often involves multiple steps. It typically begins with damage to the genetic material of a cell, leading to mutations. If these mutations affect genes that control cell growth and division, the cell may begin to divide uncontrollably. Over time, further genetic alterations can accumulate, leading to the formation of a tumor and potentially metastasis. The classification of carcinogens is an ongoing process by organizations like the International Agency for Research on Cancer (IARC), which categorizes agents based on the strength of scientific evidence for their carcinogenicity in humans and animals.