FAO Nutrition Meetings 
    Report Series No. 48A 
    WHO/FOOD ADD/70.39


    The content of this document is the 
    result of the deliberations of the Joint 
    FAO/WHO Expert Committee on Food Additives 
    which met in Geneva, 24 June  -2 July 19701

    Food and Agriculture Organization of the United Nations
    World Health Organization


    1 Fourteenth 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.


    Biological data

    Biochemical aspects

         Brominated olive oil has been used for radiography in man and
    animals without apparent deleterious effects. Bromide ions may be very
    slowly released during metabolism of brominated oils (Cortell, 1941;
    1956). Feeding of brominated maize oil appears to cause an
    accumulation of organically bound bromine in adipose tissues and organ
    fat of the rat, pig and man, and this lipid-bound bromine is released
    slowly. The exact chemical form in which this organically bound
    bromine is present in tissue fats is not yet known (BIBRA, 1970). Rats
    fed 0.8% brominated maize oil for 25 weeks accumulated bromine to a
    maximum of 10 000 ppm in their body fat after 8 weeks. This level
    remained stationary during the remaining 17 weeks. Only 30% of the
    bromine disappeared in the following 8 weeks on a normal diet no
    change in level having been noted for the first two weeks. Starvation
    merely increased the bromine concentration in body fat without
    mobilisation of lipid-bound bromine (Gaunt et al., 1968).

    Acute toxicity

         Five groups of 2-4 rats each were fed brominated olive oil at
    levels of 15 000, 10 000, 5 000, 3 000 and 1 000 mg/kg bodyweight per
    day. All animals on the three highest doses died by the third or
    fourth day, those on 3 000 mg/kg died by the 8th day, but those on the
    lowest dose level survived 10 days. No significant pathological
    lesions were found at autopsy when compared with controls fed
    comparable amounts of olive oil (Cortell, 1941; 1956).

         Brominated cottonseed oil was administered orally to groups of 5
    male rats in doses of 2 500, 5 000 and 10 000 mg/kg/day. After 4 days
    of treatment all rats on the highest dose and 3 out of 5 on the middle
    dose had died. The survivors and those on the lowest dose were
    lethargic and had decreased body temperatures and respiration rates
    (Munro et al., 1969).

    Short-term studies


         Three groups of 16 young male and female rats were fed for 8
    weeks either 0.5% brominated olive oil, plain olive oil or 0.22%
    sodium bromide (equivalent to the total bromine in oil) in their diet.
    There were no significant differences from controls regarding growth,
    urine analysis, haematology and histological examination of liver and
    kidney (Cortell, 1941; 1956).

         Five groups of 16 male and 16 female rats were fed for 90 days
    brominated maize oil in their diet at 0, 0.05%, 0.2% and 0.8% with
    0.8% of plain maize oil as positive control. No significant effects on
    growth, haematological indices, renal function tests or serum
    chemistry were observed. Maize oil caused a mild degree of fat
    deposition randomly distributed within the liver lobules. At the 0.8%
    and 0.2% level there was enlargement and fatty infiltration of the
    liver and kidneys. Periportal fatty infiltration of the liver was also
    seen at the 0.05% level. At the 0.8% level the hepatocytes were
    enlarged and foamy. Lipid-bound bromine was found at all levels in
    adipose tissue after 13 weeks (Gaunt et al., 1968).

         Three groups of 20 male rats were fed semi-purified diet
    containing 0, 0.5% or 2.5% of brominated cottonseed oil for 80 days.
    Growth and food utilization were impaired at the highest level and
    mild anaemia was noted. The liver, heart, kidneys and spleen were
    enlarged at the 2.5% level and the heart also at the 0.5% level. All
    rats had thyroid hyperplasia, myocarditis, fatty changes in the liver,
    arrested testicular development, renal tubular epithelial changes and
    reduced liver enzyme activities (Munro et al., 1969).

         In another experiment groups of rats were fed 0, 0.02%, 0.1% and
    0.5% of brominated cottonseed oil in the diet for 100 days.
    Enlargement of the heart appeared at the 0.5% level only, as well as
    accumulation of lipid in liver and heart. The activities of the
    hepatic drug metabolizing enzymes and isocitric dehydrogenase were
    normal but that of glucose 6 -phosphate dehydrogenase was reduced at
    the 0.1% and higher level. There was minimal liver pathology but the
    hearts of some animals even at the 0.1% level showed degenerative
    lesions (Munro et al., 1970).

         In another experiment groups of 15 male and female rats were fed
    0%, 0 0% or 0.5% brominated cottonseed, corn, olive and sesame oils
    for 105 days. Animals at the 0.5% levels showed degenerative heart
    lesions with interstitial oedema, swollen cells, hyaline degeneration
    and pyknotic nuclei. Lesions progressed to myocytolysis and mild
    infiltration with mononuclears. Lipid accumulated in the liver and
    microfollicular thyroid hyperplasia was seen. Only 2 animals at the
    0.1% level showed mild myocardial changes. The heart weights of all
    animals at the 0.5% level were elevated except for brominated olive
    oil. All kidney and liver weights were increased at the 0.5% level.
    Hearts of animals on brominated cottonseed oil had reduced capacity to
    metabolize palmitic acid when fed 400 mg/kg bodyweight per day for 3
    days (Munro et al., 1970).


         Groups of 2 miniature pigs were fed brominated maize oil for 42
    days at 100 or 400 mg/kg/day. Tissue analysis showed the accumulation
    of lipid-bound bromide in adipose tissue, liver, spleen, adrenals,
    brain, kidney and lymph nodes. No organic bromine was detected in
    serum or urine. Histology showed no abnormalities apart from very
    slight fatty accumulation in the liver (Crampton, 1968).

         In another experiment single pigs were given 0, 20, 40, 80 or 160
    mg/kg/day brominated vegetable oil for 64 days, followed by 109-178
    days on normal diet. Biopsy of subcutaneous adipose tissue showed dose
    related accumulation of bromine with a fall in the rate of
    accumulation after 20 days. When put on a control diet there was a
    very slow decrease in absolute amounts of lipid-bound bromine. All
    organs examined contained lipid-bound bromine (Crampton, 1968).

    Long-term studies

    None available.

    Observations in man

         Bromine estimation in human adipose tissue fat and other organ
    fats from Holland, Germany and U.K. revealed high levels of
    lipid-bound bromine only in that country which permitted the use of
    brominated vegetable oil as a food additive. High levels of
    lipid-bound bromine were found particularly in children up to the age
    of 15, the levels in adults being very much lower. Lipid-bound bromine
    increased in organ fat in an age-related manner and levels were much
    higher in the fat extracted from brain, liver and spleen than from
    adipose tissue. Body fat from countries not using brominated vegetable
    oils contained only minimal lipid-bound bromine. Apparently no
    chemical abnormalities were associated with bromine storage (British
    Indust. Biol. Res., Assoc., 1970).


         Brominated vegetable oils were considered at the Ninth FAO/WHO
    Expert Committee meeting of Food Additives (FAO/WHO, 1966) but not
    evaluated because of lack of suitable data. Attention was then drawn
    to the necessity for providing evidence on cumulation and subsequent
    release of bromine in body lipids. Recent evidence has demonstrated
    accumulation of bromine in the body lipids of the rat, pig and man
    (particularly children). Despite the absence of any definite
    pathological effects in man, it seems undesirable that lipid-bound
    bromine should accumulate in the tissues of man. Progressive cardiac
    lesions have been noted in the rat at comparatively high levels of
    intake. No long-term studies are available to define a no-effect


         The absence of a no-effect level based on long-term studies
    precludes the establishment of any formal ADI.

    Further work required

         Long-term studies using various forms of brominated vegetable
    oil, commonly used commercially, with particular emphasis on bromine
    storage in tissues and on cardiac pathology.

         The significance of bromine deposition in body lipids should be
    determined and the possibility investigated of an epidemiological
    relationship to cardiac disease in man.

         Identification of the brominated derivative(s) accumulated in the
    fat of animals and man as well as a study of their toxicological


    British Industrial Biological Research Association (1970) BIBRA
    Information Bulletin (in press)

    Cortell, R. (1941) Unpublished report submitted to WHO

    Cortell, R. (1956) Assoc. F. D. Off., USA Quart. Bull., 20, 71

    Crampton, R.F., Gaunt, I.F. & Gangoli, S.D. (1968) BIBRA Research
    Report No.5 Unpublished report submitted to WHO

    FAO/WHO (1966) FAO Nutrition Meetings Report Series No.40; Wld Hlth
    Org. techn. Rep. Ser., 339

    Gaunt, I.F., Grasso, P. & Gangoli, S.D., (1968) BIBRA Research Report
    No.6 submitted to WHO

    Munro, I.C., Middleton, E.J. & Grice, H.C. (1969) Fd. Cosmet.
    Toxicol., 7, 25

    Munro, I.C., Middleton, E.J. & Salam, K. (1970) Unpublished report
    submitted to WHO

    See Also:
       Toxicological Abbreviations