INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
WORLD HEALTH ORGANIZATION
TOXICOLOGICAL EVALUATION OF SOME
FOOD COLOURS, EMULSIFIERS, STABILIZERS,
ANTI-CAKING AGENTS AND CERTAIN
FAO Nutrition Meetings Report Series
No. 46A WHO/FOOD ADD/70.36
The content of this document is the result of the deliberations of the
Joint FAO/WHO Expert Committee on Food Additives which met in Rome,
27 May - 4 June 19691
Food and Agriculture Organization of the United Nations
World Health Organization
1 Thirteenth report of the Joint FAO/WHO Expert Committee on Food
Additives, FAO Nutrition Meetings Report Series, in press;
Wld Hlth Org. techn. Rep. Ser., in press.
Treatment with epichlorhydrin under alkaline conditions up to 0.3 per
cent. tends to produce cross-linking at a rate of one glycerol diether
linkage per 220 - anhydroglucose units.
Much evidence in the literature points to etherified starches being
somewhat resistant to enzymic degradation. Probably small fragments
containing the ether linkage will remain and will not be absorbed
readily. Any material absorbed is likely to be excreted by the kidney.
No direct experimental evidence exists for this particular hypothesis.
(French, 1960), The metabolic fate of methylglucose is cited as
collateral evidence. Although methylglucose is absorbed by rats (Sols,
1956) no demethylation is believed to occur (Czáky & Wilson, 1956) and
excretion is essentially quantitative (Csáky & Glean, 1957). The
caloric value of two starches treated at levels of 0.07 per cent. and
0.50 per cent. epichlorhydrin were estimated by comparing the weight
gain obtained after feeding a basal diet supplemented with 3 g of each
starch against a dose-response curve obtained by feeding daily sucrose
supplements of O, 1.5 g, 3 g, 4.5 g and 6 g equivalent to
approximately 0, 6, 12, 18 and 24 calories. Distarch glycerols were
only slightly lower in caloric value than unmodified starch, the
differences not being significant. No details were available on the
number of rats used or the length of feeding of a given
supplementation (Oser, 1960).
Rat. Groups of 10 male and 10 female rats were fed for 90 days
unmodified starch or starch treated with 0.07 per cent.and 0.50 per
cent. epichlorhydrin at 71 per cent. of their diet. The efficiency of
food utilization was similar as between all groups. Haematological
investigations showed no abnormalities related to the feeding of
modified starches. Non-protein nitrogen and sugar levels in the blood
remained normal in all groups. The weights of kidney, liver and
adrenals were normal and no histopathological changes were seen in the
liver or kidney. Only a summary report was available (Oser, 1960).
Although only minor structural modifications are stated to be present
in this material the biological information provided lacks full
particulars and was not adequate for evaluation. No experimental
evidence was provided on the metabolic fate of this compound. Adequate
metabolic studies preferably in man as well as 90-day studies in two
species (one a non-rodent mammal) are required.
Not possible on the data available.
Csáky, T. Z. & Wilson, J. E. (1956a) Biochem. Biophys. Acta., 22,
Csáky, T. Z, & Glenn, J. E. (1956b) Amer. J. Physiol., 188, 159
French, D. (1960) Communication to T. A. White, 20th January 1960
Oser, B. L. (1960) Unpublished report by Food and Drug Research
Laboratories Inc., 4th January 1960, submitted by National Starch
Sols, A. (1956) Rev. esp. Fisiol., 12, 17