INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
WORLD HEALTH ORGANIZATION
TOXICOLOGICAL EVALUATION OF SOME
FOOD COLOURS, EMULSIFIERS, STABILIZERS,
ANTI-CAKING AGENTS AND CERTAIN
OTHER SUBSTANCES
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.
POLYGLYCEROL ESTERS OF INTERESTERIFIED RICINOLEIC ACID
Biological Data
Biochemical aspects
Twelve rats fed for 10 weeks a diet containing 1 per cent. or 10 per
cent. groundnut oil or 1 per cent groundnut oil + 9 per cent. of the
substance were divided into two groups. One was fed a fat-free diet
for six days, the other group was fed test or control diets. No
acetone or acetoacetic acid was detected in any urine, pointing to
absence of interference with fat metabolism.
Three groups of 10 male and six female rats fed 45 weeks on diets
containing either 1 per cent. or 10 per cent. groundnut oil or 1 per
cent. groundnut oil + 9 per cent. of the substance ware given three
days later an additional 9 per cent. groundnut oil for seven days. No
differences between tests and control groups were detected regarding
oil absorption, protein digestibility or diet digestibility.
Three groups of 10 male and six female rats were fed diets containing
9 per cent. or 18 per cent. groundnut oil or 9 per cent. groundnut oil
+ 9 per cent. of the substance. Clearing of lipaemic plasma by heparin
was similar in all three groups and plasma turbidity was not
increased. Chylomicron concentration in rats before and after feeding
the substance in their diet showed absence of alimentary
chylomicronaemia. Absorption does therefore not occur into intestinal
lymphatics although a specific test to confirm absorption into portal
capillaries was not done.
Three groups of rats were fed four weeks on diets containing 1 per
cent. or 10 per cent. groundnut oil or 1 per cent. groundnut oil + 9
per cent. of the substance. Digestibility of the substance was 98 per
cent.
Another three groups of two male and two female rats were fed eleven
weeks on diets containing either 1 per cent. or 10 per cent. groundnut
oil or 1 per cent. groundnut oil + 9 per cent. of the substance. No
adverse influence was noted on fat storage, body composition and
vitamin A content of the liver; the substance was not stored
significantly in the body fat.
The in vitro action of lipase on groundnut oil was not affected by
the presence of the substance (Unilever Research Laboratories, 1966).
Acute toxicity
Animal Route LD50 Reference
mg/kg body-weight
rat oral > 18 500 Unilever Research
Labs, 1966
rat i.p. > 12 000 "
No mortality could be obtained, though animals received up to 47.5
g/kg daily for 5 days (Unilever Research Laboratories, 1966).
Short-term studies
Rat. Three groups of eight male and eight female rats were fed a
diet containing either 1 per cent. or 10 per cent. groundnut oil or 1
per cent. groundnut oil + 9 per cent. of no substance for 30 weeks. No
adverse effects on growth, food intake and faecal appearance were
noted. During this test all three groups were restricted to 5 g fat
free diet for 17 days and then realimented. No difference in weight
gain was noticeable, nor in carcass and liver fat amounts or
composition. The test group on the substance had a shorter
Bromosulphophthalein retention time. The specific gravity of the urine
was comparable in all groups. Organ weights of liver, kidney, adrenal,
testes and spleen were similar in all groups. In view of the special
design of the study, the statement on absence of significant changes
in liver weight applies only to three groups of selected animals not
participating in the food restriction experiment, i.e. two female and
four male rats on 1 per cent. groundnut oil, four female and three
male rats on 10 per cent. groundnut oil and two female and five male
rats on 1 per cent. groundnut oil + 9 per cent. of the substance.
Despite the small numbers the test may be taken to indicate that 9 per
cent. of the substance was not causing liver enlargement when fed for
30 weeks.
In another study three groups of 10 male and six female rats were kept
on diets containing either 1 per cent. or 10 per cent. groundnut oil
or 1 per cent. groundnut oil + 9 per cent. of the substance for 45
weeks. No adverse effect on growth or food intake was noted, The
groups were comparable as regards Bromosulphophthalein retention,
specific gravity of urine, haematological indices and red cell
fragility. Organ weights of kidney, adrenal, testes and spleen were
similar in all groups but the liver weights of rats fed of the
substance (9 per cent. of the diet) were significantly higher than the
controls. Similar effects were seen in rats fed castor oil. This was
not due to an increased blood volume of the liver (Unilever Research
Laboratories, 1966).
Man. Nineteen male and female volunteers, aged 19-24 years, took 5 g
of the substance per day for one week and 10 g per day for another
week using constant dietary fat intake. Serum protein, albumin and
globulin levels were unaffected. Thymol turbidity, serum bililubin,
SGBT, serum cholesterol and serum cholinesterase were normal (Unilever
Research Laboratories, 1963).
Long-term studies
Mouse. Four groups of 25 male and 25 female mice were fed a diet
with 5 per cent. groundnut oil or the substance with no additional fat
for 80 weeks. A positive control group received 0.5 mg, 9,
10-dimethyl-1,2-benzanthracene once per week for 16 weeks. After 50
weeks there was no difference in growth between test and groundnut oil
groups but the basic diet and positive control group showed reduced
growth. Survival was comparable for the three groups, also the
haematological indices. Liver and kidney of the test group were
significantly heavier than the controls. No specific histological
lesion was seen. Carcass fat contained no polyglycerol but only a
small amount (0.1 per cent.) of ricinoleic acid. Histopathology of all
other major tissues showed no lesions specifically associated with the
substance nor was there any significant difference in tumour
incidence. The strain was sensitive to the carcinogen used in the
positive control.
Groups of 20 male and 20 female mice were given repeated s.c.
injections of 0.5 ml of the substance weekly for five weeks with milk
or groundnut oil as controls. After 80 weeks no adverse effects were
noted on growth, survival, haematology, organ weights and
histopathological findings. Tumour incidence was similar in test and
control groups.
Seven groups of 20 male and 20 female mice were painted daily with 20
mg of the substance for 60 weeks with or without a single preceding
application of 0.25 mg dimethylbenzanthracene and a positive control
group was included. After 80 weeks no adverse effects were noted on
growth, survival or tumour incidence in tests and controls involving
the substance. There was no promoting or cutaneous carcinogenic effect
(Unilever Research Laboratories, 1966).
Rat. A three-generation test was carried out in two groups of 19 and
28 rats on diets containing 0 per cent. or 1.5 per cent. of the
substance. No significant differences were seen between the two groups
as regards fertility, pup weight, pup survival, litter number, etc.
Each animal was observed for over one year. No consistent
abnormalities or histopathological changes were seen in the third
generation.
In another experiment two groups of 30 male and 60 female rats each
were fed diets containing five per cent. of the substance or five per
cent. groundnut oil for 104 weeks. No significant adverse effects were
seen on growth, food consumption, liver function tests at weeks 89 and
103, specific gravity of the urine at weeks 89 and 103, or survival.
The kidneys of males and females at five per cent. of the substance
and the livers of females at five per cent. of the substance were
significantly enlarged. There was no polyglycrol or ricinoleic acid
accumulation in carcass fat. Histopathology of all organs showed no
abnormalities related to the substance administration nor was there a
rise in tumour incidence in the test group. The strain was sensitive
to 20-methylcholanthrene.
Thirty male and 30 female rats were injected s.c. with 0.5 ml twice
weekly for 13 weeks at different sites, milk and groundnut oil were
controls. After two years there were no adverse effects on growth,
survival, haematological indices, organ weights or histopathology of
all tissues. No increase in tumour incidence was found but most rats
treated with the substance developed persistent nodules at injection
sites.
Six groups of 10 male and 10 female rats were painted with 50 mg of
the substance cutaneously daily for 60 weeks with or without a single
preceding application of 0.25 mg benzanthracene and observed for two
years. A positive control group was included. No deleterious effects
were noted on growth and survival. No skin tumours were seen in the
test group. The strain was sensitive to the carcinogen used as
positive control (Unilever Research Laboratories, 1966).
Comments
The metabolic fate of this material has been studied by a number of
indirect measurements. In-vivo studies, using labelled material, are
not available. The long-term studies in rats and mice did not show
carcinogenic potential. The enlargement of liver and kidneys observed
in long-term tests was not accompanied by any lesions detectable by
histopathology. Only the rat study shows a no-effect level for liver
enlargement. No satisfactory explanation of the observed organ
enlargements has been offered.
EVALUATION
Level causing no toxicological effect in the rat
1.5 per cent. (= 15 000 ppm) in the diet equivalent to 750 mg/kg
bodyweight per day.
Estimate of acceptable daily intake for man
mg/kg body-weight
Temporary acceptance 0 - 3 75
Further work required by June 1972
In-vivo metabolic studio in several species to determine more
directly the fate of the major polymers in the material. A 90-day
study in a non-rodent mammalian species to establish a no-effect level
for organ enlargement. Investigation of the causes of the observed
hepatic and renal enlargements.
REFERENCES
Unilever Research Laboratories (1966) Unpublished report submitted to
WHO