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
30 BLACK 7984
EVALUATION FOR ACCEPTABLE DAILY INTAKE
BIOLOGICAL DATA
BIOCHEMICAL ASPECTS
The dye is poorly absorbed from the gastrointestinal tract after
oral administration to rats. Up to 5 g/kg body weight leaves the rat
carcass unstained but faeces are black. When given parenterally to
mice the whole animal is coloured intensely, this being fully
reversible after 12 hours. After i.v. injection of 50 mg/kg body
weight into dogs up to 10% is excreted unchanged in the urine some
13% appears as a coloured metabolite (monoazo naphthyl-amino
disulfonic acid) while 80% are not accounted for. Only traces of
p-sulfanilic acid appear in the urine. Rapid reductive splitting of
the azo linkages between the two naphthalene rings occurs (Hecht,
1960a).
Acute toxicity
Animal Route LD50 mg/kg Reference
body weight
Mouse intravenous 1 000 mg Hecht, 1960a
Rat oral 5 000 mg Hecht, 1960a
Rats given 1.5 g/kg body weight orally for 19 days showed no
Heinz bodies (Hecht, 1960a). Cats given 100 mg/kg body weight/day for
eight days and 5 mg/kg body weight/day for 31 days showed no increase
in Heinz bodies (Hecht, 1960a).
Special tests
Guinea-pig
When given s.c. 10 doses of 1 ml of a 0.05-0.1% isotonic saline
solution of the colour for a period of 21 days no intolerance was
noted. A challenge test for sensitization after 14 days was negative
(Hecht, 196Oa).
Rabbit
Repeated intracutaneous injections of 0.1 ml of a 5% aqueous
solution over a few days produced no skin abnormalities (Hecht,
196Oa).
Short-term studies
Rat
The dye was fed to 10 rats for 200 days at a level of 0.1% in the
diet. The animals grew normally and no toxic effects were noted
(Hecht, 1960a).
Long-term studies
Rat
Two groups of 10 male rats were given 0 or 0.5% of the dye in
their drinking water (0.038 g/kg body weight) for 543 days. After this
period animals continued on normal diet for up to 822 days. The total
intake of colour was approximately 53 g/animal. No abnormalities as
regards growth, survival or histopathology were seen and no tumours
were found (Hecht, 1960a).
In another experiment two groups of 25 male and 25 female rats
were given 0 or 0.5% of the colour (average 600 mg/kg body weight) in
their drinking water for 337 days and observed for up to 1184 days.
Controls were observed up to 1013 days. After 337 days the animals
received normal drinking water. Mortality of males only was greater in
the test group after 24 months compared with male controls. At 30
months six test females and one control female survived. Nine mammary
fibro-adenomas of the breast and one ovarian tumour occurred in female
test animals, one sarcoma and five breast fibroadenomas in control
females. No extensive pathology was done (Hecht, 1960b).
One group of 10 male rats was given twice a week 0.5 ml of a 1%
solution (5 mg) s.c. After 105 injections (365 days) the
administration was stopped and the last animal died on the six hundred
and twenty-seventh day. Average survival was 600 days. No subcutaneous
tumours were found (Hecht, 1960). In another experiment a group of 25
male rats were given s.c. 0.5 ml of 2% solution (equiv. 10 mg) for 72
administrations (280 days). The last animal died on the one thousand
and twenty-seventh day (average 525 days). No subcutaneous or other
tumours were found (Hecht, 1960a).
A more recent study (Gangolli et al., 1972), in which Black 7984
was compared with other dye-stuffs for protein binding and their
ability to produce subcutaneous sarcomas, showed that Black 7984
produced very mild, self-limiting local reactions although its ability
to bind to serum proteins was high. This work supported the conclusion
that food colourings which can firmly bind to proteins influence the
rate of absorption from the site of subcutaneous injection which leads
to the eventual production of local sarcomas.
Reproduction studies
Rat
Four females and one male from each group of the second rat study
were used as parent generation to breed an F1 generation after eight
months on 0.5% Black 7984 in their drinking water. The F1 pups were
kept for 110 days, after weaning on 0.5% dye in their drinking water
and killed after 146 days. From 19 F1 females an F2 generation was
bred. Twenty-three F2 females were kept on 0.5% dye in their drinking
water after weaning for 360 days and then continued on normal drinking
water up to 800 days. A similar group of 18 F2 male and 25 F2 female
controls were observed for a similar period of 28 months. No
abnormalities were noted regarding growth, reproduction or any other
effects (Hecht, 1960b).
REFERENCES
Gangolli, S. D., Grasso, P., Goldberg, L. and Hooson, J. (1972)
Protein binding by food colorings in relation to the production of
subcutaneous sarcoma, Fd. Cosmet. Toxicol, 10, 449-462
Hecht, G. (1960a) quoted in R. Truhaut (1962), Estratto dei Rendiconti
dell' Instituto Superiore di Sanita, XXV, 796-920 (Quotation in text
only)
Hecht, G. (1960b) Private communication to WHO. Typewritten
unpublished document from Forbenfebrik Bayer AG. Paper transmitted to
the Subcommittee on the Health Control of Foodstuffs of the Council of
Europe