Toxicological evaluation of some food
additives including anticaking agents,
antimicrobials, antioxidants, emulsifiers
and thickening agents
WHO FOOD ADDITIVES SERIES NO. 5
The evaluations contained in this publication
were prepared by the Joint FAO/WHO Expert
Committee on Food Additives which met in Geneva,
25 June - 4 July 19731
World Health Organization
Geneva
1974
1 Seventeenth Report of the Joint FAO/WHO Expert Committee on
Food Additives, Wld Hlth Org. techn. Rep. Ser., 1974, No. 539;
FAO Nutrition Meetings Report Series, 1974, No. 53.
ASCORBYL PALMITATE AND STEARATE
Explanation
Ascorbyl palmitate was evaluated for acceptable daily intake by
the Joint FAO/WHO Expert Committee on Food Additives (see Annex 1,
Ref. No. 6) in 1961 and ascorbyl stearate in 1969 (see Annex 1, Ref.
No. 20).
The previously published monographs are reproduced in their
entirety below.
BIOLOGICAL DATA
BIOCHEMICAL ASPECTS
No information available.
TOXICOLOGICAL STUDIES
Special studies
No information available.
Acute toxicity
Animal Route LD50 References
(kg bw)
Mouse oral 25 g Tokita
(undated)
Short-term studies
Rat
Groups of 10 young rats were fed diets containing L-ascorbyl
stearate in concentrations providing 100, 200, 500, 1000 and
3000 mg/kg bw for six months. No adverse effects were noted (Tokita).
Groups of 10 rats each were fed for nine months on normal diets
and diets containing 2% and 5% of ascorbyl palmitate. At the 5% level
the growth rate was significantly retarded, and two of the 10 rats had
numerous bladder stones and hyperplasia of the bladder epithelium.
Another rat in this group showed an inflammatory condition in the
kidney. There was a slight retardation of growth in the rats on the
diet containing 2% of ascorbyl palmitate, but there were no
significant differences between these rats and the controls in respect
of mortality and histopathology (Fitzhugh & Nelson, 1946).
Long-term studies
Rat
Heat-treated lard containing 1% or 5% of L-ascorbyl palmitate
(0.05% or 0.25% of the total diet) was fed for two years to groups of
10 rats each. No adverse effects were observed in any of the
experimental animals as determined by growth rate, mortality and
pathological examination (Fitzhugh & Nelson, 1946).
No direct evidence is available on the long-term effects of
L-ascorbyl stearate. However, L-ascorbyl palmitate was fed to rats for
two years (Fitzhugh & Nelson, 1946), no adverse effects being noted at
the 0.5% or 0.25% levels as determined by growth rate, mortality and
pathological examination. Food grade palmitic acid of that time period
normally contained significant amounts of stearic acid as evidenced by
a statement from a major United States producer of fatty acids. It is
a reasonable inference that the L-ascorbyl palmitate used in the
feeding study probably contained L-ascorbyl stearate.
Comments:
Since the material tested contained 5 to 20% stearate and 80 to
95% palmitate, the study of commercial ascorbyl palmitate can be used
for evaluation. The adverse effect in rodents of bladder stone
formation are not considered significant for man.
EVALUATION
Level causing no toxicological effect
2500 ppm (0.25%) in the diet equivalent to 125 mg/kg bw
Estimate of acceptable daily intake for man
0-1.25* mg/kg bw
REFERENCES
Fitzhugh, O. G. & Nelson, A. A. (1946) Proc. Soc. exp. Biol., 61, 195
Tokita (undated) Unpublished report from Toho University, submitted
1968
* As ascorbyl stearate or ascorbyl palmitate, or the sum of both.