From Our 2011 Archives
8 'New' Cancer Causes
U.S. Adds 8 Chemicals -- Some Common -- to Carcinogen List
By Daniel J. DeNoon
Reviewed by Laura J. Martin, MD
June 10, 2011 -- There are now eight new substances on the official U.S. list of toxins known to cause or suspected of causing cancer.
There are now 240 agents on the list, maintained by the National Toxicology Program (NTP). The NTP lists agents in two categories: those known to cause cancer, and those expected to be added to the "known carcinogen" list once there's more scientific evidence.
It's not possible to totally avoid exposure to carcinogens, says John Bucher, PhD, associate director of the NTP, a part of the National Institutes of Health.
"We are exposed to small levels of carcinogens every day: in drugs, in chemicals, in sunlight, in tanning beds, in tobacco smoke, over and over every day," Bucher said at a news teleconference. "This report is just to allow people to have the information they need to make choices every day. Simply avoid using products containing these substances if you are uncomfortable with the risk."
Most of the known risk comes from industrial exposures to workers at manufacturing plants. It's not clear how much risk, if any, comes from the many consumer products that emit small amounts of these carcinogens.
Bucher says he's not worried about his own daily exposures. "I probably won't be making many changes," he said.
The two new known carcinogens are aristolochic acids and formaldehyde.
Aristolochic acids are the active ingredient in a number of unsafe herbal remedies. The FDA has been warning Americans about these herbs since 2000. All herbal remedies suspected of containing aristolochic acid are banned in the U.S. and in Europe.
Formaldehyde is used to manufacture a wide range of products. The most common source of formaldehyde exposure is cigarette smoke. Cars and wood stoves give off formaldehyde, but most exposure comes from indoor air. New home finishing products and consumer goods such as some hair-smoothing/straightening products, cleaning agents, and glues may contain formaldehyde.
The six agents now "reasonably anticipated to be carcinogens" are:
Listing of a substance as a carcinogen by the NTP does not limit its use. However, NTP determinations are used by agencies such as the FDA and OSHA as the basis for regulations.
SOURCES: News conference, National Toxicology Program, June 10, 2011.John Bucher, PhD, associate director, National Toxicology Program.News release, National Toxicology Program.National Toxicology Program web site.National Toxicology Program, 12th Report on Carcinogens, June 2011. ©2011 WebMD, LLC. All Rights Reserved.