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.
OXYSTEARIN
Explanation
This substance has been evaluated for acceptable daily intake by
the Joint FAO/WHO Expert Committee on Food Additives (see Annex 1,
Ref. No. 20) in 1969.
Since the previous evaluation, additional data have become
available and are summarized and discussed in the following monograph.
The previously published monograph has been revised and is reproduced
in its entirety below.
BIOLOGICAL DATA
BIOCHEMICAL ASPECTS
Analyses of diets and faeces of rats maintained for one month in
diets containing 5 to 15% oxystearin, showed that 70% of the ingested
oxystearin was absorbed. Liver lipids remained normal, but carcass
lipids showed decreasing iodine values, with increasing dietary
oxystearin (Mattson, 1951). In another experiment, utilization of the
ether soluble material at three and 15 months in rats maintained on a
15% oxystearin diet was 61 to 83% (Hodge, 1954).
TOXICOLOGICAL STUDIES
Acute toxicity
Rat
Per os, intraperitoneally, LD50 have not been established.
Female rats were able to tolerate doses as high as 15 g/kg without any
marked ill-effects (Hodge, 1952).
Short-term studies
Rat
Groups each of 20 rats (10 of each sex) were maintained for 30
days on diets containing 0, 0.5, 2.0 and 20% oxystearin. No deaths
occurred. Retarded growth rates were reported at the 20% level. Organ
weights were normal (Hodge, 1952).
In another study, groups of 20 rats (10 of each sex) were
maintained on diets containing 0, 0.15, 5, 10 and 15% oxystearin for
one month. There was no effect on weight gain or haematological
indices of blood. The weights of all organs were normal (Hodge, 1952).
Dog
A single female dog tolerated a diet containing 25% oxystearin
for one month. Haematologic indices of blood were normal as were
urine, sugar and protein. At autopsy, organ weights were within normal
limits and there were no compound related histological changes (Hodge,
1952).
Groups each of four dogs (two of each sex) were fed diets
containing 0, 0.25 and 2.5% oxystearin for one year. Observations
included general condition, growth rate, food intake, urine analyses,
haematologic indices of blood, organ weight and histopathology. All
findings were negative (Hodge, 1954).
Long-term studies
Mouse
300 mg per week of oxystearin was administered to the skin of 38
mice in three doses for 75 weeks. The tumour index (% - weeks) was
negative for a cotton-seed oil control, a 40% solution of oxystearin
in cotton-seed oil, and a 40% unsaponifiable fraction of oxystearin in
cotton-seed oil. The positive control methylcholanthrene had a tumour
index of 89% (Horton, 1956).
Rat
Groups each of 100 rats (50 of each sex) were fed a diet
containing 0, 0.5, 5.0 and 15.0% oxystearin for two years. There was
no indication that oxystearin shortened the life span. Growth rate and
food consumption was normal, with the exception of the 15% group,
where there was a slight retardation in growth during the first 90
days, but this difference had disappeared by the end of the first
year. Urine analyses gave normal values for sugar and protein.
Haematological indices of blood were normal, with the exception of
females at the 15% level, where there was a slight depression in
haemoglobin and red blood cell counts. At autopsy, organ weights were
normal with the exception of liver weight, at the 5 and 15% level. No
histological changes occurred in the liver or other organs and tissues
examined that could be related to the test substances. A study of
femur length and radiographs of these bones showed no effect on bone
structure (Hodge, 1954).
A three generation reproduction study in rats selected from the
0, 0.5 and 5% groups (16 females and eight males), showed that there
were no effects on reproductive performance as measured by number of
pregnancies, rats born, pups per litter, mortality 0-5 days, 6-12
days; and average weight at end of 21 days. Organ weights of the F3b
generation were within normal range; although organ/body weight ratios
of test groups were greater than control, because of slightly lower
body weight of these groups (Hodge, 1954).
Comments:
Metabolic studies indicate that the fatty acids are absorbed and
utilized and there are adequate short-term and long-term studies
available for assessment. There is no evidence of accumulation of the
saturated fatty acids in the liver cells, although compositional
changes in body fat are reported. Provision is made in the
specification for limitation of epoxide content.
EVALUATION
Level causing no significant toxicological effect
Rat: 50 000 ppm (5%) in the diet equivalent to 2500 mg/kg bw.
Estimate of acceptable daily intake for man
0-25 mg/kg bw.
REFERENCES
Hodge, H. (1952) Unpublished report, Procter & Gamble Co.
Hodge, H. (1954) Unpublished report, Procter & Gamble Co.
Horton, A. W. (1956) Unpublished report, Procter & Gamble Co.
Mattson, F. H. (1951) cited in Hodge, H. (1952) Unpublished report
submitted by Procter & Gamble Co.
See Also:
Toxicological Abbreviations
Oxystearin (FAO Nutrition Meetings Report Series 46a)
OXYSTEARIN (JECFA Evaluation)