Cancer Causing Agents - Carcinogens
The US federal government released the 11th edition of the Report on Carcinogens (December, 2004). This Report, published every two years by the National Institute of Environmental Health Sciences, identifies substances and circumstances that are "known" or are "reasonably anticipated" to cause cancer . Seventeen substances have been added to the growing list of cancer-causing agents, bringing the total to 246. For the first time ever, viruses are listed in the report: hepatitis B virus, hepatitis C virus, and some human papillomaviruses that cause common sexually transmitted diseases. Other new listings include lead and lead compounds, X-rays, compounds found in grilled meats, and a host of substances used in textile dyes, paints and inks.
"Among U.S. residents, 1 in 2 men and 1 in 3 women will develop cancer at some point in their lifetimes. Research shows that environmental factors trigger diseases like cancer, especially when someone has a family history," said Kenneth Olden, Ph.D., director of the National Institute of Environmental Health Sciences and the National Toxicology Program, which prepared the report for HHS.
The Report on Carcinogens, Eleventh Edition, referred to as the "RoC," lists cancer-causing agents in two categories -- "known to be human carcinogens" and "reasonably anticipated to be human carcinogens." The report now contains 58 "known" and 188 "reasonably anticipated" listings. Federal law requires the Secretary of the Department of Health and Human Services to publish the report every two years.
Because of the importance of cancer and agents which may cause it, we here provide some of the highlights of this Report.
Listing in the Report
A listing in the Report does not by itself establish that a substance presents a cancer risk to an individual in daily life.
The Report also does not try to balance the potential benefits of exposures to certain carcinogenic substances in special situations. For example, a number of drugs used to treat cancer have been shown to increase the occurrence of secondary cancers. In these instances, the benefits of exposure to the drugs for treatment or prevention of a specific disease have been determined by the Food & Drug Administration (FDA) to outweigh the additional cancer risks associated with their use. People should not make decisions concerning the use of a given drug, or any other listed agent, based solely on the information contained in the Report. Decisions of this type should be made only after consulting with a physician or other appropriate specialist about both risks and benefits.
"Known" versus "Reasonably Anticipated" To Be a Carcinogen
An agent or exposure can be listed in the Report as "known to be a human carcinogen" or as "reasonably anticipated to be a human carcinogen."
The "known" category is reserved for those substances for which there is sufficient evidence of carcinogenicity from studies in humans that indicates a cause and effect relationship between the exposure and human cancer.
The "reasonably anticipated" category includes those substances for which there is limited evidence of carcinogenicity in humans and/or sufficient evidence of carcinogenicity in experimental animals.
Six substances have been added to the "known" category: