Select Committee on GRAS Substances (SCOGS) Opinion: Carrageenan
The GRAS Substances (SCOGS) Database allows access to opinions and conclusions from 115 SCOGS reports published between 1972-1980 on the safety of over 370 Generally Recognized As Safe (GRAS) food substances. The GRAS ingredient reviews were conducted by the Select Committee in response to a 1969 White House directive by President Richard M. Nixon.
- SCOGS-Report Number: 6*
- Type Of Conclusion: 3
- ID Code: 9000-07-1
- Year: 1973
- 21 CFR Section: 172.620
The available information on the oral administration of undegraded carrageenan at levels greatly exceeding the daily human intake, reveals evidence of possible adverse effects on the gastrointestinal epithelium. Extensive recent investigations of carrageenan and the pathogenesis of gastrointestinal changes indicates the susceptibility of the guinea pig to ulcerative colitis when fed relatively high levels of carrageenan in the diet. The work suggests that the occurrance of ulcers in the large bowl of animals is a species-specific phenomenon where feeding of carrageenan can induce ulceration in the caecum and proximal colon of the guinea pig which to date, does not appear to occur in the rat, mouse, hamster, pig, squirrel monkey, or man.
Recent reports on the oral administration of undegraded sodium and calcium carrageenan of known quality to pregnant animals reveals fetotoxic effects, with or without frank teratogenic effects, in some species at levels that do not greatly exceed the average daily human rate of intake. These effects appear to be dose-dependent.
While carrageenan exhibits no mutagenic effects as measured by the host-mediated and dominant lethal assay procedures, significant abnormalities appear to be induced in the anaphase figures of human embryoic lung cells in tissue culture at dosages that are slightly above average daily human intake.
It is of further concern that parenterally administered carrageenan is reported to inhibit the activity of complement, exert cytotoxic effects on macrophages, suppress delayed hypersensitivity reactions in some tuberculin sensitive animals, activate factors causing procoagulant activity in human blood platelets, increase vascular permeability, and liberate kinin in vitro, all of which point to the possibility of the generation of toxic effects that could cause adverse responses following the oral consumption of carrageenan if, during pregnancy or in the presence of infectious challenge or metabolic disorder, appropriate amounts of carrageenan should be absorbed from the gastrointestinal tract.
The Select committee has been informed that additional animal feeding and teratologic studies are soon to be initiated on commercial carrageenan and on several of the separated polysaccharide components of carrageenan. The Committee's opinion should be reviewed once the results of these studies become available.
The Select Committee has weighed the foregoing and concludes that:
While no evidence in the available information on undegraded carrageenan demonstrates a hazard to the public when it is used at levels that are now current and in the manner now practiced, uncertainties exist requiring that additional studies should be conducted.
*Complete reports containing details of the safety studies that formed the basis of the opinions and conclusions and are available from the National Technical Information Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161 (703) 605-6000.