Select Committee on GRAS Substances (SCOGS) Opinion: Distarch Phosphate
- SCOGS-Report Number: 115*
- Type Of Conclusion: 2
- ID Code: 55963-33-2
- Year: 1979
- 21 CFR Section: 172.892
Because of their close structural relationship, monostarch phosphate, distarch phosphate and phosphated distarch phosphate are considered as a group. Digestibilities of these modified starches were similar to those of the corresponding unmodified starches as measured by caloric values and growth rates determined in rat feeding experiments. No differences were noted between distarch phosphates cross-linked by treatment with trimetaphosphate or phosphorus oxychloride. No significant gross or histological changes or dose-related responses in clinical chemical indices were observed in gO-day rat feeding studies with distarch phosphate or phosphated distarch phosphate. Neither were adverse effects observed in a 3-generation reproduction and lactation study with phosphated distarch phosphate. A possible exception in the 2 -year rat feeding study was a kidney abnormality which consisted mainly of focal hyperplasia of the renal papillary and pel vic epithelium accompanied by calcified patches in the underlying tissues. Incidence of the lesion was not distinctly dose related and, as discussed earlier, is considered to be of doubtful toxicological significance.
Other than the occurrence of the renal changes which are of doubtful biological significance, no adverse effects were found in the long-term feeding experiments with phosphated distarch phosphate. Because of the relationship in structure, the results for this starch derivative would appear also to apply to distarch phosphate. Studies with monostarch phosphate have shown that the phosphorus in the 32 P-labeled starch derivative administered orally to rats is metabolized in a manner similar to the phosphorus in radiolabeled disodium phosphate, a substance evaluated in another report of the Select Committee. Thus, the monophosphate ester group would be expected to be removed in the digestion of phosphated distarch phosphate, presenting fragments of starch chains cross-linked by phosphate linkages such as would be present in distarch phosphate.
In view of the foregoing evidence, the Select Committee concludes that:
There is no evidence in the available information on monostarch phosphate, distarch phosphate, and phosphated distarch phosphate that demonstrates or suggests reasonable grounds to suspect a hazard to the public when they are used at levels that are now current and in the manner now practiced. However, it is not possible to determine, without additional data, whether a significant increase in consumption would constitute a dietary hazard.