Carcinogens are indeed environmental factors that can cause cancer. They are substances or agents that can alter the genetic material in our cells, leading to the development of cancer. Exposure to carcinogens can occur through various means such as inhaling, ingesting, or coming into contact with these substances. Carcinogens can be found in various forms such as chemicals, pollutants, radiation, and certain infectious agents. Therefore, it is correct to say that carcinogens are environmental factors that can contribute to the development of cancer.