1879 — Johns Hopkins University chemists Ira Remsen and Constantin Fahlberg publish their first paper describing benzoic sulfimide, which became known as saccharin.
1901 — Monsanto is founded to produce saccharin in the U.S.
1907 — An official of the U.S. Department of Agriculture investigates whether using saccharin in place of sugar violates the 1906 Pure Food and Drug Act. President Theodore Roosevelt, a saccharin consumer, opposes the investigation.
1909 — A panel from the USDA's Office of Consulting Scientific Experts reports that saccharin is safe in small doses (less than 1/2 gram per day) and is probably safe in large doses (up to 4 pounds per day). Remsen is the panel's chairman.
1911 — The same panel rules that foods containing saccharin are considered "adulterated," thus banning their production. A subsequent ruling makes an exception for patients who must avoid sugar.
World War I — Sugar shortages prompted the government to suspend restrictions on the use of saccharin in processed foods.
1950s — Dieters embrace saccharin as the artificial sweetener makes its way into a variety of low-calorie foods.
1969 — Scientists at the U.S. Food and Drug Administration discover animal studies from the 1940s that show diets containing up to 5% saccharin are safe.
1972 — The FDA removes saccharin from the list of substances "generally recognized as safe" after it was found to increase the risk of bladder cancer in rats.
1977 — Studies by Canadian researchers prompt the FDA and the National Academy of Sciences to propose a ban on saccharin. The studies show that high amounts of saccharin cause cancer in rats.
1977 — A federal law requires all saccharin-containing products to include a warning label stating that the sweetener causes cancer in animals.
1981 — Based on animal studies, the National Toxicology Program declares that saccharin is "reasonably anticipated to be a human carcinogen."
2000 — Further data from human studies prompted the NTP to remove saccharin from its list of carcinogens. President Clinton signs a new federal law that does away with warning labels for food and drinks.
2001 — The FDA declares saccharin is safe for human consumption.
2010 — The U.S. Environmental Protection Agency removes saccharin from its list of hazardous substances.