Saccharin Dropped From Cancer List
(05-15-2000: WASHINGTON (AP) – More than two decades after a study in rats prompted scientists to link saccharin to human cancer, the federal government is dropping the artificial sweetener from its list of cancer-causing chemicals.
Officials at the National Institute of Environmental Health Sciences said Monday that new studies show "no clear association" between saccharin and human cancer.
The announcement came with the release of the 9th National Toxicology Report on Carcinogens, an every-other-year listing of chemicals that the federal agency believes cause, or possibly cause, cancer.
"Two decades ago, when saccharin was shown to produce bladder tumors in rats, it was a prudent, protective step to consider the sweetener to be a likely human carcinogen," said Dr. Kenneth Olden, director of the NIEHS and the National Toxicology Program.
But Olden said an advance in scientific understanding "allows us to make finer distinctions today... In other words, with better science we can now make a better call."
Studies now show that laboratory rat bladder tumors once linked to saccharin are known to be "not relevant to the human situation," Olden said, adding that decades of human saccharin use "adds to our confidence."
The action follows three years of new studies and scientific reviews about the effects of saccharin, the announcement said.
Saccharin previously had received a clean bill of health from such groups as the American Cancer Society, the American Medical Association, the American Dietetic Association and the American Diabetes Association.
The carcinogen report also delisted ethyl acrylate, a chemical used in the manufacture of latex paints and textiles. It had been listed in 1989 as "reasonably anticipated to be a human carcinogen." A review of lab studies showed the chemical caused cancer in rats only when it was fed to the animals in high concentrations. Human exposure in such a way, the report said, "is unlikely."
The report contains a total of 218 cancer-causing substances.
Formal additions to the list of "known human carcinogens" include environmental tobacco smoke; directly inhaled tobacco smoke; smokeless tobacco (such as snuff); alcoholic beverages; sunlamps and sunbeds, and six industrial chemicals and dyes. Many studies already have linked these substances to cancers and the new listing formally recognizes the link.
Also added to the list was tamoxifen. Although it fights breast cancer, the drug also increases the risk of uterine cancer.
Seven chemicals, including diesel exhaust particulates, were added to the list of substances "reasonably anticipated to be human carcinogens. The other additions are industrial chemicals.
Linking saccharin to cancer originated with 1977 laboratory studies in which male rats fed huge doses of the sweetener developed bladder tumors. Some compared the dosage to a human drinking 800 cans of diet soda daily for a lifetime.
The studies led the Food and Drug Administration call for a ban on saccharin, but Congress in 1977 placed a moratorium on the FDA ban. That moratorium was renewed periodically.
Congress did pass legislation requiring all saccharin products to carry a label warning that the sweetener "may be hazardous to your health" because it caused cancer in lab animals.
The 1981 Report on Carcinogens first listed saccharin as an "anticipated human carcinogen."
But human studies soon began to question the dangers of the sweetener and in 1991, the FDA withdrew its proposed ban.
With the delisting from the carcinogen report, saccharin supporters will next ask Congress to remove the warning label, said Keith Keeney of the Calorie Control Council, an association of diet food and beverage manufacturers.
Saccharin is the oldest of the common artificial sweeteners. It was discovered by Johns Hopkins University chemist Constantine Fahlberg in 1879 and was used in diets starting early in the 20th century, particularly during wartime when sugar supplies were short. Use increased in the 1950s when diet foods became more popular.
There are three other artificial sweeteners now in wide commercial use -- aspartame, sucaralose and acesulfame potassium - none of which has been linked to cancer, Keeney said.