The International Agency for Research on Cancer (IARC) released a report in which it classifies a common artificial sweetener—aspartame—as a Group 2B carcinogen. The Food and Drug Administration first approved aspartame for use in 1974.
For several decades, IARC has been classifying various chemicals and compounds into four categories:
- Group 1: Carcinogenic to humans
- Group 2A: Probably carcinogenic to humans
- Group 2B: Possibly carcinogenic to humans
- Group 3: Not classifiable as to its carcinogenicity as to humans
In defining aspartame as a Group 2B carcinogen, IARC is saying that based on its review of human epidemiology, animal studies and mechanistic data, it believes aspartame is possibly carcinogenic due to an association with hepatocellular carcinoma. According to IARC, “a classification of Group 2B means that there is convincing evidence that the agent causes cancer in experimental animals but little or no information about whether it causes cancer in humans. This category can also be used when there is some evidence that the agent could cause cancer in humans and in experimental animals but neither the evidence in humans nor the evidence in experimental animals is convincing enough to permit a definite conclusion to be drawn. There may also be consistent mechanistic evidence, showing that the agent exhibits one or more of the recognized key characteristics of human carcinogens.” By its own definition, a Group 2B classification also means that IARC could not rule out chance, bias or confounding in its review of human epidemiology.
IARC has classified multiple everyday compounds as Group 2B carcinogens—including aloe vera, pickled vegetables, carrageenan, melamine, titanium dioxide and nickel—as well as common activities such as using cell phones and occupational exposures to dry cleaning, textile manufacturing, printing, carpentry and road paving.
Some of IARC’s classifications have resulted in mass tort litigation, such as litigation targeting glyphosate-based herbicides, talc, gasoline and diesel fuel. IARC’s classification of aspartame may trigger similar lawsuits alleging injury as a result of its consumption via food and beverage products. Experienced counsel can provide guidance on assessing exposure and preparing for any anticipated litigation.