INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
WORLD HEALTH ORGANIZATION
SUMMARY OF TOXICOLOGICAL DATA OF CERTAIN FOOD ADDITIVES
WHO FOOD ADDITIVES SERIES NO. 13
The data contained in this document were examined by the
Joint FAO/WHO Expert Committee on Food Additives*
Rome, 3-12 April 1978
Food and Agriculture Organization of the United Nations
World Health Organization
* Twenty-second Report of the Joint FAO/WHO Expert Committee on Food
Additives, Geneva, 1978, WHO Technical Report Series No. 631
BRILLIANT BLACK PN
This food colour was evaluated by the 1974 and 1977 Joint FAO/WHO
Expert Committee on Food Additives. Since the previous evaluation,
additional data have become available and are summarized below.
At concentrations of 2-400 mg/litre the colour inhibits pepsin
but not lipase (Diemair and Häusser, 1951) and at 12.5 mg/litre it
inhibits trypsin inconsistently (Diemair and 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) 1' amino 7' sulfonaphthalene (Saenz
Lascano Ruiz and 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 brilliant black PN is
metabolized in the caecum of the rat (Ryan and 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.
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 and Richeri, 1960).
Animal Route LD50 mg/kg/bw References
Oral >5 000 DFG, 1957
Mouse >2 000 Gaunt et al., 1967
i.p. 550-1 000 Gaunt et al., 1967
Oral >5 000 Gaunt et al., 1967
1 100 Gaunt et al., 1967
Rat i.p. >2 000 DFG, 1957
i.v. approximately DFG, 1957
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 and
Griepentrog, 1960). A cat fed 0.1 g/kg bw per day for seven days
developed no Heinz bodies (DFG, 1957).
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).
Groups of three male and three female pigs were fed black PN
at dose levels of 0, 100, 300 or 900 mg/kg/day for 90 days. No
abnormalities in appearance or behaviour were observed. There were no
consistent or dose-related differences in body weight gain,
haematology, urinalysis, levels of serum glutamic-oxalacetic and
glutamic-pyruvic transaminases or organ weights. Haematology and
urinalysis were conducted at six and 13 weeks while serum
transaminases were estimated at autopsy. At necropsy no abnormalities
were observed in control or in the group receiving 100 mg/kg. In one
female at the 300 mg/kg and in two of each sex at the 900 mg/kg group,
hard nodules were present in the mucosa of the ileum. Histological
examination showed that the nodules consisted of collection of cysts
within the mucus membrane. These cysts were lined by epithelial cells,
contained mucus and fibrin and were infiltrated with polymorphonuclear
leucocytes (Gaunt et al., 1969).
Groups of 30 male and 30 female mice were fed diets containing
0.1, 0.25, 0.5 or 1% (approximately equivalent to 130, 325, 650 or
1300 mg/kg/day) of black PN for 80 weeks. Groups of 60 mice of each
sex served as controls. No dose-related effects were observed in
mortality, body weight gain, haematology, relative organ weights or
histopathology. The incidence of tumours in the treated mice did not
exceed that of the control animals (Drake et al. 1977).
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 and 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
0.45 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 (approx. 5 mg) for 365 days and was observed for 653
days. The total amount per animal is 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 two
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).
Bär, F. and Griepentrog, F. (1960) Med. u. Ernähr., 1, 99
Deutsche Forschungsgemeinschaft (1957) Farbstoff Komission,
Mitteilung, 6, 58
Diemair, W. and Häusser, H. (1951) Z. Lebensmitt.-Untersuch., 92,
Diemair, W. and Boeckhoff, K. (1953) Z. Analyt. Chem., 139, 35
Drake, J. J. P., Butterworth, K. R., Gaunt, I. F. and Grasso, P.
(1977) Long-term toxicity study of black PN in mice, Food Cosmet.
Toxicol., 15, 503
Gaunt, I. F., Farmer, M., Grasso, P. and Gangolli, S. D. (1967) Acute
(mouse and rat) and short term (rat) toxicity studies on black PN,
Food Cosmet. Toxicol., 5, 171
Gaunt, I. F., Colley, J., Creasey, M. and Grasso, P. (1969) Short term
toxicity of black PN in pigs, Food Cosmet. Toxicol., 7, 557
Gaunt, I. F., Campanini, F. M. B., Grasso, P. and Kiss, I. S. (1972)
Long-term feeding study on black PN in rats, Food Cosmet. Toxicol.,
Hecht, G. and Wingler, A. (1960) Arzneimittel-Forsch., 2, 192
Lück, H. and Richerl, E. (1960) Z. Lebensmitt.-Untersuch., 112,
Piekarski, L. (1960) Roczniki P2H, 11, No. 4, p. 353
Ryan, A. J. and Welling, P. G. (1970) The metabolism and excretion of
black PN in the rat and man, Food Cosmet. Toxicol., 8, 487-497
Saenz Lascano Ruiz, I. and Laroche, C. (1960) Ann. Fals. Exp. Chim.,