INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
WORLD HEALTH ORGANIZATION
SUMMARY OF TOXICOLOGICAL DATA OF CERTAIN FOOD ADDITIVES
WHO FOOD ADDITIVES SERIES NO. 12
The data contained in this document were examined by the
Joint FAO/WHO Expert Committee on Food Additives*
Geneva, 18-27 April 1977
Food and Agriculture Organization of the United Nations
World Health Organization
* Twenty-first Report of the Joint FAO/WHO Expert Committee on Food
Additives, Geneva, 1977, WHO Technical Report Series No. 617
PONCEAU SX
EVALUATION FOR ACCEPTABLE DAILY INTAKE
BIOLOGICAL DATA
BIOCHEMICAL ASPECTS
When ponceau SX was given orally in doses of 100 mg to rats, only
2% of unchanged dye was found in the faeces, but when it was
administered slowly by intrasplenic infusion to rats with cannulated
bile ducts 82% of the administered doses was excreted in the bile and
4% in the urine within eight hours. Products of reductive cleavage of
the colour, 2-amino-l-hydroxy-4-naphthalenesulfonic acid, 1-amino-2,
4-dimethyl-5-benzenesulfonic acid and 2-acetamino-l-hydroxy-4-
naphthalenesulfonic acid were found in the urine of rats fed the
colour (Radomski and Mellinger, 1962).
These results are in agreement with the findings that ponceau SX
is rapidly reduced by bacteria obtained from the intestines of rats.
Three amines were detected by thin-layer chromatographs in the
incubation mixture (Roxon et al., 1967).
After intravenous injection of ponceau SX into rats with bile
fistulae, 66-71% of the dye was excreted in bile within four hours.
The rate of excretion of ponceau SX (and of amaranth under the same
conditions) varied with the dose (Iga et al., 1970).
Special studies on carcinogenicity
Oral administration
Groups of 50 male and 50 female C57BL/He mice and similar groups
of C3Heb/Jax mice were fed a diet containing 10 000 or 20 000 mg
commercial ponceau SX per kg of diet for two years. Two groups of
100 male and 100 female mice of each strain were fed a control diet.
In C57BL/He mice fed the 10 000 mg/kg or 20 000 mg/kg levels, tumours
occurred in 8/47 (six hepatomas, one reticulum-cell sarcoma and one
other) and 12/56 (one mammary tumour, nine hepatomas and two others),
respectively, compared with 13/91 (12 hepatomas and one reticulum-cell
sarcoma) in controls. No tumours were reported in 50 and 28 C3Heb/Jax
mice fed ponceau SX at each level, respectively, compared with 5/66 in
controls (the numbers of animals given are those examined for
pathology). In treated animals, 56-67% survived 52 weeks, compared
with 91% of control C57BL/He and 58% of control C3Heb/Jax mice (Davis
et al., 1966).
A group of five male and five female Wistar rats was fed a diet
containing 40 000 mg ponceau SX per kg of diet for up to 18 months. In
1/7 rats living to a tumour-bearing age, a mesenteric lymphosarcoma
was observed. No tumours occurred in 50 controls surviving for
20 months or more (Willheim and Ivy, 1953). (The limited number of
animals used was noted by the Working Group.)
Five groups, each containing 12 male and 12 female Osborne-Mendel
rats, were fed a diet containing 0 (control), 5000, 10 000, 20 000 or
50 000 mg commercial ponceau SX per kg of diet for two years. Growth
effect was negligible and there was no effect on survival, haematology
or on weights of heart, liver, kidneys, spleen and testes at autopsy.
Benign and malignant tumours, mainly pulmonary lymphosarcomas, mammary
fibroadenomas and mammary adenocarcinomas, occurred in 10/19, 8/23,
10/22 and 5/24 rats in the respective treatment groups, compared with
7/16 controls (the numbers of animals given are those whose organs
were examined microscopically) (Davis et al., 1966).
Additional experiments, using groups of 200, 100 and 100 Osborne-
Mendel rats of both sexes and 200, 100 and 100 Sprague-Dawley rats of
both sexes fed a diet containing 0, 10 000 or 20 000 mg ponceau SX per
kg of diet, resulted in tumour incidences of 67/171 (39%), 23/89 (26%)
and 32/89 (36%) in Osborne-Mendel rats and 38/147 (26%), 16/83 (19%)
and 14/74 (19%) in Sprague-Dawley rats in the respective groups (the
numbers of animals given are those examined for pathology). Survival
rates at 80 weeks were 79, 75 and 78%, respectively, in Osborne-Mendel
rats and 61, 66 and 54%, respectively, in Sprague-Dawley rats (Davis
et al., 1966).
In a group of 50 non-inbred rats given ponceau SX in the diet at
a concentration of 20 000 mg/kg of diet on six days a week for 33
months (total dose, 107-139 g), 4/38 rats surviving at the appearance
of the first tumour developed tumours, including three subcutaneous
sarcomas and one hepatoma. No tumours were reported to have occurred
in 50 controls surviving up to 33 months (Andrianova, 1970).
Commercial ponceau SX was fed at a level of 0, 10 000 and
20 000 ppm in the diet to five female beagle dogs (age six months) for
up to seven years; three dogs died at six, nine-and-one-half and 64
months of treatment. A second group of five females received ponceau
SX at a level of 10 000 mg/kg of diet for seven years, while nine
females served as controls. Two (20 000 ppm), five (10 000 ppm) and
nine (control) dogs, respectively, survived the seven years of
treatment. There was no apparent effect on weight gain during the
first six months or any change on haematological parameters examined
at any time during the duration of the experiment. Haemorrhagic
streaks and/or projections in the urinary bladder of all test animals
surviving more than six months were found. Microscopically the lesions
varied from small submucosal haemorrhages to blood-filled mucosal
projections usually without clots or fibrous stalk projections. Most
of the affected bladders also had lymphocytic foci in the muscular
layer. The most important microscopic lesion attributable to the
compound was a moderate to marked atrophy of the zone glomerulose in
the adrenals of all test animals. There was no consistent effect on
other zones of the adrenal cortex. In some instances there was partial
replacement of the zone glomerulose by a subcapsular zone of
pigmented, foamy macrophages. In dogs of both dose levels small foci
of pigmented hepatic cells were observed. In one dog at the highest
dose level congestion and haemorrhages in the ileum and mesenteric
lymph nodes were found. Of dogs fed the 20 000 mg/kg level, two had
adrenal cortical adenomas and one had a follicular-cell adenoma of the
ovary. Of the dogs fed the 10 000 mg/kg level, one had an adrenal
medullary adenoma, one a mammary adenocarcinoma. In the control dogs,
two had adrenal cortical adenomas, two hyperplastic foci in the
mammary glands and one nodular hyperplasia in the liver (Davis et al.,
1966).
Subcutaneous and/or intramuscular injection
Groups of 50 male and 50 female C57BL/He mice and similar groups
of C3Heb/Jax mice received monthly s.c. injections of either 0.5 ml of
a 2% aqueous solution of commercial ponceau SX or 0.5 ml of saline.
About 60% of both control and experimental animals survived 52 weeks
or more. In C57BL/He mice, 3/59 controls and 1/59 test animals
developed tumours (two mammary tumours and one hepatoma in controls,
one other tumour in treated animals), whereas in C3Heb/Jax mice, 0/69
controls and 2/66 treated mice developed tumours (Davis et al., 1966).
Groups of 50 male and 50 female Osborne-Mendel rats and similar
groups of Sprague-Dawley rats received weekly s.c. injections of
either 1 ml of a 2% aqueous solution of commercial ponceau SX or 1 ml
of saline. Survivors at 80 weeks were 70% and 82% for control and test
rats of the Osborne-Mendel strain and 61% and 56% for the Sprague-
Dawley rats, respectively. No tumours at the site of injection
occurred in 98 and 99 controls, compared with 1/100 and 2/98 in
treated animals. The total tumour incidence was 29/98 in controls,
compared with 33/100 in treated Osborne-Mendel rats, and 18/99
controls, compared with 20/98 in treated Sprague-Dawley rats. Tumours
were mainly mammary fibroadenomas, adenocarcinomas and lymphosarcomas
of the lung. No tumours occurred in controls which were not found in
treated animals, other than tumours at the site of injection (Davis et
al., 1966).
Acute toxicity
The oral LD50 in male Wistar rats was > 2 g/kg body weight
(Lu and Lavallée, 1964).
Short-term studies
No data available.
Long-term studies
(See carcinogenicity studies.)
REFERENCES
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amaranth, SX purple and 4R purple, Vop. Pitan., 29, 61-65
Davis, K. J., Nelson, A. S., Zwickey, R. E., Hansen, W. H. and
Fitzhugh, O. G. (1966) Chronic toxicity of ponceau SX to rats, mice
and dogs, Toxicol. appl. Pharmacol., 8, 306-317
Iga, T., Awazu, S., Hanano, M. and Nogami, H. (1970) Pharmacokinetic
studies of biliary excretion. I. Comparison of the excretion behaviour
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Roxon, J. J., Ryan, A.D. and Wright, S. E. (1967) Reduction of water-
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