INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
WORLD HEALTH ORGANIZATION
TOXICOLOGICAL EVALUATION OF SOME
FOOD COLOURS, ENZYMES, FLAVOUR
ENHANCERS, THICKENING AGENTS, AND
CERTAIN FOOD ADDITIVES
WHO FOOD ADDITIVES SERIES 6
The evaluations contained in this publication were prepared by the
Joint FAO/WHO Expert Committee on Food Additives which met in Rome,
4-13 June 19741
World Health Organization Geneva 1975
1 Eighteenth Report of the Joint FAO/WHO Expert Committee on
Food Additives, Wld Hlth Org. techn. Rep. Ser., 1974, No. 557.
FAO Nutrition Meetings Report Series, 1974, No. 54.
BRILLIANT BLACK PN
BIOLOGICAL DATA
BIOCHEMICAL ASPECTS
At concentrations of 2-400 mg/litre the colour inhibits pepsin
but not lipase (Diemair & Mäusser, 1951) and at 12.5 mg/litre it
inhibits trypsin inconsistently (Diemair & Boeckhoff, 1953).
Intravenous injection into rabbits and dogs of 50 mg/kg produced only
small amounts in the urine (Hecht, 1960). Heated in the presence of
reducing sugars the colour is partially decomposed and gives an orange
derivative, isolated by paper chromatography, which is the disodium
salt of 4' (4-sulfo-l-phenylazo) l'amino 7' sulfonaphtalene (Saenz
Lascano Ruiz, & Laroche, 1960).
"Rats were given Brilliant Black PN. During the experimental
work, the faeces and urine of the animals were collected and the
presence of the dye was noted in faeces and not in the urine.
Quantitative determination of the dye in the faeces indicated that,
from the total amount of the dye administered to the rats, 0.6% was
excreted in the faeces (Piekarski, 1960).
It has been shown that orally administered Black Brilliant PN is
metabolized in the caecum of the rat (Ryan & Welling, 1970). The
presence of coloured faeces in this study showed that, at the dosage
levels used, some of the dye passed through the gastrointestinal
system unchanged. Similar observations were made by Gaunt et al.
(1967) in rats and Gaunt et al. (1969) in pigs.
TOXICOLOGICAL STUDIES
Special studies on mutagenicity
The colour was tested for mutagenic effect in a concentration of
0.5 g/100 ml in cultures of Escherichia coli. No mutagenic effect
was found (Lück & Richerl, 1960).
Acute toxicity
LD50
Animal Route mg/kg bw Reference
Oral > 5 000 DFG, 1987
Mouse > 2 000 Gaunt et al., 1967
i.p. 500-1 000 Gaunt et al., 1967
Oral > 5 000 Gaunt et al., 1967
Rat i.p. 1 100 Gaunt et al., 1967
> 2 000 DFG, 1957
i.v. 2 500 DFG, 1957
approx.
Five rats were given 1.5 g/kg bw orally for 22 days. No Heinz
bodies were found (DFG, 1957). In an experiment with guinea-pigs it
was found that this colour had no sensitization activity (Bar &
Griepentrog, 1960). A cat fed 0.1 g/kg bw per day for seven days
developed no Heinz bodies (DFG, 1957).
Short-term studies
Rat
Groups of 16 male and 16 female weanling rats were fed diets
containing 0, 0.3%, 1.0%, and 3.0% colour for 90 days. Growth
retardation associated with diminished food intake was evident only
in males at the 3% level. This was shown by a paired feeding test.
Haematological examination, liver and kidney function tests were
normal. Organ weight of testes and kidneys increased in males at the
3% level only. No untoward histopathological findings were seen (Gaunt
et al., 1967).
Long-term studies
Rat
Sixteen rats were fed Black PN at 0.1% of the diet (average daily
intake 0.06 g/kg bw) for 410 days and were observed for 761 days. The
total dose per animal was 5.6 g. One rat died prematurely. No tumours
were observed (Hecht & Wingler, 1952; DFG, 1957).
Another group of 10 rats was given 0.5% Black PN in their
drinking water (average daily intake 0.5 g/kg bw) for 384 days and
observed 545 days. Total intake per animal was 20 g. No tumours were
seen (DFG, 1957). In a second experiment a group of 10 rats was again
given 0.5% Black PN in their drinking water (average daily intake
0.46 g/kg bw) for 502 days and observed for 923 days. Total intake per
animal was 50 g. No tumours were noted (DFG, 1957).
A group of 10 rats received twice weekly subcutaneously 0.5 ml
of a 1% solution (= 5 mg) for 365 days and was observed for 653 days.
The total amount per animal was 0.5 g. Two animals died prematurely
but no tumours were noted (DFG, 1957).
"Groups of 24 male and 24 female weanling rats were fed for 2
years on diets containing 0, 1000, 5000 or 10 000 ppm Brilliant Black
PN. No effects attributable to treatment were found in respect to
mortality, food intake, body weight gain, haematology, blood serum
chemistry, renal concentration tests, organ weights or incidence of
pathological findings, including tumours (Gaunt et al., 1972)."
Comments:
Little is known about the metabolism of this colour. The earlier
long-term studies in rats using oral administration in the diet or
drinking water did not reveal carcinogenicity but were inadequate as
regards the numbers of animals used and the parameters studied. Later
long-term studies in the mouse and rat did not reveal any significant
adverse effects due to administration of the compound. Reproduction
and embryotoxicity including teratology studies are not available.
EVALUATION
Level causing no toxicological effect
Rat: 1% (= 10 000 ppm) in the diet equivalent to 500 mg/kg bw.
Estimate of acceptable daily intake for man
0-2.5 mg/kg bw*
FURTHER WORK OR INFORMATION
Required by June 1978
(a) metabolic studies preferably including man;
(b) adequate reproduction and embryotoxicity including
teratological studies.
* Temporary.
REFERENCES
Bar, F. & Griepentrog, F. (1960) Med. u. Ernähr., 1, 99
Deutsche Forschungsgemeinschaft (1957) Farbstoff Komission,
Mitteilung, 6, p. 58
Diemair, W. & Häusser, H. (1951) Z. Lebensmitt.-Untersuch., 92, 165
Diemair, W. & Boeckhoff, K. (1953) Z. Analyt. Chem., 139, 35
Gaunt, I. F. et al. (1967) Fd. Cosmet. Toxicol., 5, 171
Gaunt, I. F. et al. (1969) Fd. Cosmet. Toxicol., 7, 557
Gaunt, I. F. et al. (]972) Fd. Cosmet. Toxicol., 10, 17
Hecht, G. & Wingler, A. (1952) Arzneimittel-Forsch., 2, 192
Lück, H. & Richerl, E. (1960) Z. Lebensmitt.-Untersuch., 112, 157
Piekarski, L. (1960) Roczniki PZH, 11, No. 4, p. 353
Ryan, A. J. & Welling, P. G. (1970) Fd. Cosmet. Toxicol., 8, 487
Saenz Lascano Ruiz, I. & Laroche, C. (1960) Ann. Fals. Exp. Chim.,
53, 581