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    TOXICOLOGICAL EVALUATION OF CERTAIN FOOD ADDITIVES



    WHO FOOD ADDITIVES SERIES 10





    The evaluations contained in this document were prepared by the
    Joint FAO/WHO Expert Committee on Food Additives*
    Rome, 21-29 April 1976



    Food and Agriculture Organization of the United Nations

    World Health Organization




    *Twentieth Report of the Joint FAO/WHO Expert Committee on Food
    Additives, Geneva, 1976, WHO Technical Report Series No. 599, FAO Food
    and Nutrition Series No. 1.

    GALLATES, DODECYL, OCTYL AND PROPYL

    Explanation

         These compounds have been evaluated for acceptable daily intake
    for men by the Joint FAO/WHO Expert Committee on Food Additives in
    1961, 1964, 1972 and 1973 (see Annex I, Refs No. 6, p. 60; No. 8,
    pp. 22-23; No. 31, p. 75; No. 33, p. 183).

         Since the previous evaluation, additional data have become
    available and are summarized and discussed in the following monograph.
    The previously published monograph has been expanded and is reproduced
    in its entirety below.

    BIOLOGICAL DATA

    BIOCHEMICAL ASPECTS

         The available evidence indicates that the esters are hydrolysed
    in the body. Most of the gallic acid is converted into 4-O-methyl
    gallic acid. Free gallic acid or a conjugated derivative of 4-O-methyl
    gallic acid is excreted in the urine. Conjugation of the 4-O-methyl
    gallic acid with glucuronic acid was demonstrated (Booth et al.,
    1959).

         Rats fed a low-methionine, low-choline diet containing 1% gallic
    acid developed fatty livers which could be prevented by added choline
    or methionine (Booth et al., 1961).

         The detailed metabolic pathways for propyl gallate have been
    described (Dacre, 1960). There is no evidence to suggest that other
    esters of gallic acid differ greatly in their metabolism from the
    pattern described for propyl gallate.

    TOXICOLOGICAL STUDIES

    Special studies on mutagenicity

    (a)  Cytogenetics

         Propyl gallate was investigated in vitro at concentrations of
    0.5, 5.0 and 50 µg/ml employing WI-38 human embryonic lung cells for
    anaphase abnormalities. It was also investigated in vivo by the
    cytogenetic analysis of metaphase cells from the bone marrow of rats
    (Sprague Dawley C-D strain). The dosages employed were 5.0, 50.0 and
    500 mg/kg. Propyl gallate was non-mutagenic in both assays (Weir and
    Brusick, 1974).

    (b)  Host-mediated assay

         In vitro - Salmonella TA-1530 and G-46 together with
    Saccharomyces D-3 were employed. A 0.25% concentration was tested.
    Propyl gallate was non-mutagenic to all organisms.

         In vivo - Propyl gallate was tested at 5.0, 50.0 and 500 and
    2000 mg/kg in ICR Swiss mice employing as indicator organisms,
    Salmonella G-46 and TA-1530 and Saccharomyces D-3. Propyl gallate
    was non-mutagenic to all organisms (Weir and Brusick, 1974).

    (c)  Dominant lethal test

         Sprague Dawley C-D strain male rats were used. Dosages of 5.0,
    50.0 and 500 mg/kg and 5000 mg/kg were employed.

         Acute study - a single dose was administered with subsequent
    mating for each of eight weeks. Propyl gallate did not produce any
    significant dominant lethalityś

         Subacute - five daily doses were administered (5 × 5.0, 5 × 50.0,
    5 × 500 and 5 × 5000 mg/kg). The additional dose was investigated in
    an attempt to obtain some degree of toxicity at the highest level.
    Males were subsequently mated for each of seven weeks. No dominant
    lethal effects were noted (Weir and Brusick, 1974).

    Special studies on reproduction

    Rat

         n-Octyl gallate was fed in the diet to groups of eight male and
    16 female rats for two successive generations at levels of 0, 0.1 or 
    0.3% (and 0.6% for one generation). Rats were mated to produce two 
    litters per generation with the next generation selected from
    weanlings of the second litter. A dietary level of 0.1% (1000 ppm) had
    no effect on reproduction performance or the offspring. At 0.3 and
    0.6% dietary octyl gallate, there was no significant effect on the rat 
    fetuses during pregnancy, but a marked effect was observed on survival 
    through weaning. In the case of the 0.6% group, return to normal diet
    for six weeks, prior to a third breeding, did not result in increased
    survival of offspring through weaning (Plank et al., 1971).

         Groups each of 10 male and 20 female rats were maintained on
    diets containing 0, 1000 or 5000 ppm (0%, 0.1% or 0.5%) of octyl
    gallate. The animals were bred twice for the first generation, and
    three times for the second generation. At the time of weaning of the
    B1B litters the 5000 ppm (0.5%) level was replaced by a 2500 ppm
    (0.25%) level for the second generation. In the case of the second
    generation approximately 24 hours after birth, selected litters were
    redistributed to female parents so that control females nursed pups
    from test animals, and test animals nursed pups from control and other

    test groups. One half P2 females bred for the third time (F2c) were
    examined by caesarean section at time of delivery and the number of
    implantation sites, corpora lutea and fetuses determined. One half of
    the pups from each litter were examined for skeletal abnormalities,
    and the other half for visceral abnormalities. The other parameters
    measured in this study were appearance, behaviour, growth of pups
    during the nursing and weaning process, fertility index, gestation
    index, live birth index, weaning survival index. Autopsies were
    carried out on F2b weanling pups, (control suckled by control, each
    groups suckled by respective group parent), as well as a microscopic
    examination of pituitary, thyroid, liver, spleen, kidneys, adrenals,
    stomach, pancreas, small intestine, large intestine and any unusual
    lesion of five males and five females, high level and control groups.
    Weaning survival index, and body weight at weaning was considerably
    reduced in the 5000 ppm (0.5%) group of the F1A and F1B generation.
    Reduction of indices was still apparent in the F2A and F2B
    generations, when the dietary level was reduced to 2500 ppm (0.25%).
    At the 1000 ppm (0.1%), the indices were similar to control.
    Redistribution of F2B pups to females of control groups, resulted in
    similar growth of all pups to weaning. Allowing pups from high level
    group to be nursed by control dams resulted in a marked increase in
    survival indices, whereas when control pups were nursed by high level
    dams, there was a marked decrease in survival indices. Examination of
    P2 parents following third breeding indicated a dose-dependent
    reduction in implantation sites, as well as a reduction in number of
    corpora lutea. Fertility index of high level P2 females was depressed
    at the F2C stage. Skeletal evaluation of F2C litters showed
    incomplete skull ossification in some pups in the test groups, but
    this was not considered remarkable for the size of the fetuses.
    Necropsy of the pups indicated a higher incidence of gross kidney
    alterations than that observed in controls. No compound-related
    histology was reported (Olson and Voelker, 1970).

    Other special studies

         Groups each of 60 rats (Wistar) equally divided by sex were
    maintained on diets containing 0, 0.002 or 0.004% propyl gallate for
    13 weeks, and then placed on fat-free diets having 20% of the
    calorific food value of the normal mean daily food intake for male
    rats for 9 weeks. Surviving animals were returned to ad lib normal
    diets for 2 to 4 weeks. During the first phase of the study, there
    were no differences in weight gain, blood composition and relative
    organ/body weight of test and control animals. During the starvation
    period, there was no difference in survival time of test and control
    groups. Chemical determination of water, protein and fat content of
    animals that were sacrificed or died, showed that there was no
    difference in protein or fat utilization chemicals on the control and
    propyl gallate groups (Tonkelaar et al., 1968).

         Gallates have been shown to cause contact dermatitis in bakers
    and other workers handling gallates. Patch tests with lauryl gallate
    at 0.2% showed a weak positive response in one sensitized individual.
    Other individuals have suffered recurring episodes of dermatitis
    presumably caused by gallates in food products (Brun, 1970).

         Repeated insult patch test with 0.1% n-octyl gallate solution
    showed an overall incidence of reaction in 13/445 or 2.9% individuals.
    Oral mucosa irritation/sensitization tests were conducted with beer
    containing 20 ppm (0.002%) n-octyl gallate and showed that the
    incidence and severity of erythema were greater with beer containing
    n-octyl gallate, than with untreated beer. Oedema was also greater
    with treated beer. Individuals that had previously shown reactions
    indicative of sensitization in the patch test were more susceptible to
    irritation (incidence and severity) than other individuals (Palazzolo
    and Fancher, 1971a, b, c).

    Acute toxicity

    DODECYL GALLATE
                                                                        

    Animal         Route     LD50 mg/kg bw       References

    Rat            oral      6 500               Sluis, 1951

    Rat            i.p.      100-120             Esch, 1955
                                                                        

    OCTYL GALLATE
                                                                        

    Animal         Route     LD50 mg/kg bw       References

    Rat            oral      4 700               Sluis, 1951

    Rat            i.p.      60-80               Esch, 1955

    Rat (male)     oral      2 710               Brun, 1970:

    Rat (female)   oral      1 960               Brun, 1970

    Rat (male)     oral      2 710               Brun, 1970

    Rat (female)   oral      2 330               Brun, 1970
                                                                        

    PROPYL GALLATE
                                                                        

    Animal         Route     LD50 mg/kg bw       References
                                                                        

    Rat            oral      3 800               Orten et al., 1948

    Rat            oral      3 600               Lehman et al., 1951

    Rat            i.p.      380                 Orten et al., 1948

    Mouse          oral      2 000-3 500         Lehman et al., 1951
                                                                        

    Short-term studies

    Rat

         Levels of propyl gallate of 1.2% and 2.3% in the diet caused
    interference with weight gain, the bitter taste of the gallate
    apparently making the diet unpalatable. The higher dose level caused
    some deaths (about 40%) during the first month; the survivors
    continued to eat the diet for 10 to 16 months and showed retarded
    growth, but no pathological lesions. The animals that died exhibited
    renal damage (Orten et al., 1948).

         Weanling rats were given diets containing 2.5% and 5% dodecyl
    gallate. All animals fed the smaller quantity were dead within 10
    days, and all animals fed the larger quantity died within seven days
    (Allen & De Eds, 1951).

         Rats fed for 70 days on a diet containing 7% fat and 0.2% dodecyl
    gallate showed no effect on body weight (Tollenaar, 1957).

         Weanling rats were fed diets which contained 20% lard and 0, 0.1, 
    0.2, 0.3, 0.4 and 0.5% propyl gallate for six weeks. There was no 
    effect on body weight, liver weight, liver weight to body weight
    ratio, left adrenal weight, total liver lipid, composition of liver
    poly-unsaturated fatty acids, liver cholesterol, adrenal cholesterol
    or serum sodium (Johnson & Hewgill, 1961).

         Propyl gallate was added to the dietary fat of weanling rats at 
    levels of 0.02% in the fat for 13 weeks. The fat content of the diet
    accounted for 30% of its calorific value. There was a very slight 
    inhibition of growth. The same rats were then placed on a partial 
    starvation diet and kept until they died. The survival time of the 
    animals which had received the propyl gallate was considerably reduced 
    and the reduction in their total body protein was greater (Buckman, 
    1962).

         Groups each of 20 rats (equally divided by sex) were maintained
    on diets containing 0, 1000, 2500 and 5000 ppm (0%, 0.1%, 0.25% and
    0.5%) of octyl gallate for 13 weeks. All groups showed normal weight
    gains, food consumption. Haematologic and blood chemistry and urine
    analyses were normal. A complete gross and histopathologic examination
    showed no compound-related effects (Blackmore and Voelker, 1969a).

    Guinea-pig

         Propyl gallate fed to guinea-pigs in groups of 20 at a level of
    0.0117% in the diet for 14 months caused no detectable ill effects
    (Orten et al., 1948).

    Dog

         Groups each of eight dogs (equally divided by sex) were fed diets
    containing 0, 0.1, 0.3% n-octyl gallate for 90 days, and 1.0% for four
    weeks; the 1.0% level has been then reduced to 0.6% for the rest of
    the study. All groups showed normal weight gains, food consumption
    (except 1.0% group). Haematologic and blood chemistry and urine
    analyses were normal. A complete gross and histopathologic examination
    showed no compound-related effects (Lindberg et al., 1970). In another
    study, groups each of eight dogs (equally divided by sex) were
    maintained on diets containing 0, 0.1, 0.25 or 0.5% octyl gallate for
    13 weeks. All animals showed normal food consumption and weight gain.
    Haematologic and urine analyses were similar for test and control
    animals. SGOT was slightly elevated in the 0.5% group. Gross and
    histopathologic examination of tissues and organs showed no compound-
    related effects (Blackmore and Voelker, 1969b).

         A level of 0.0117% of propyl gallate in the diet was well
    tolerated by a group of seven dogs over a period of 14 months (Orten
    et al., 1948).

    Pig

         Diets containing 0.2% of propyl, octyl or dodecyl gallate were
    fed to pigs without demonstrable ill effect; mo anaemia was observed
    (Esch, 1955).

    Long-term studies

    Mouse

         Groups each of 50 mice (University Animal Breeding Station closed
    strain colony) equally divided by sex were maintained on diets
    containing 0, 0.5 or 1.0% n-propyl gallate for a period of 21 months.
    Water intake and food consumption and growth of test animals was
    comparable to controls. Treated male mice showed a greater percentage
    survival than control mice at termination. Haematologic measurements

    (haemoglobin, packed cell volume differential white cell count) were
    similar for test and control animals. At autopsy, a comparison of
    relative organ/body weight showed a reduction in the relative spleen
    weight of males on the 1% diet. No compound related histopathological
    changes were observed (Dacre, 1974).

    Mouse and rat

         A level of 5% propyl gallate in the diet in a two-year chronic
    toxicity test on rats and mice gave rise to patchy hyperplasia in the
    proventiculus. At a level of 1% no difference was noted between test
    and control animals (Lehman et al., 1951).

    Rat

         Rats in groups of 10 males and 10 females were fed for two years
    on diets containing 0%, 0.00117%, 0.0117%, 0.117%, 1.17% and 2.34% of
    propyl gallate. The groups receiving 1.17% and 2.34% of propyl gallate
    showed stunted growth and evidence of renal damage. In the other
    groups, there was no detectable effect on haemoglobin, erythrocyte or
    leucocyte levels in the blood, or on the histological appearance of
    the organs examined (Orten et al., 1948).

         Propyl, octyl and dodecyl gallate were fed to rats at
    concentrations of 0.035%, 0.2% and 0.5% in the diet. Growth was
    affected only at the 0.5% level of dodecyl gallate; there was
    significant retardation, particularly in the second generation. At
    this level of dodecyl gallate, some litters were lost in the second
    generation because they were not sufficiently fed by the mothers. A
    slight hypochromic anaemia was noticed in the groups on diets
    containing 0.2% octyl and dodecyl gallate. No abnormalities were
    observed in the organs or tissues of the rats at autopsy (Esch, 1955).

         Young rats in groups of 12 males and 12 females were fed diets
    containing 7% fat and 0.2% octyl or dodecyl gallate. There was no
    significant difference between test and control animals over three
    generations (Sluis, 1951).

    Comments

         Mice fed propyl gallate at levels of 0%, 0.5% and 1% for 21
    months did not differ from controls with respect to food consumption,
    growth and haematology. Survival of treated males was better than
    their controls. At autopsy, there was reduced spleen/body weight ratio
    in male mice fed 1% propyl gallate. Histopathology was negative. This
    author calculates a no effect level to be 1500 mg/kg.

         The mutagenic potential of propyl gallate has been investigated
    in a number of test systems. Propyl gallate was found to be non-
    mutagenic.

         In a special test designed to mobilize the fat stores of propyl
    gallate-loaded rats, there was no indication of adverse effects due to
    such treatment.

         The previously stated requirement, for studies of the effect on
    reproduction of mixtures of BHA, BHT and propyl gallate, was no longer
    considered necessary by the Committee.

         The Committee was made aware of studies carried out in the USSR
    with propyl gallate. They will be evaluated when they are received.

    EVALUATION

    Estimate of acceptable daily intake for man

         0-0.2a mg/kg bw.b

    FURTHER WORK OR INFORMATION

         Submission of the results of studies in progress in the USSR.

    REFERENCES

    Allen, C. S. & De Eds, F. D. (1951) J. Amer. Oil Chem. Soc., 28, 304

    Blackmore, R. H. & Voelker, R. W. (1969a) 13-week dietary
         administration - Rats. Octyl gallate. Final report (Project No.
         458-115). Unpublished report from Hazleton Labs., Inc., Falls
         Church, Va. USA, submitted to the World Health organization by F.
         & M. Schaefer Brewing Co., Brooklyn, N.Y. USA

    Blackmore, R. H. & Voelker, R. W. (1969b) 13-week dietary feedings.
         Dogs. Octyl gallate. Final report (Project No. 458-117).
         Unpublished report from Hazleton Labs., Inc., Falls Church, Va.,
         USA, submitted to the World Health Organization by F. & M.
         Schaefer Brewing Co., Brooklyn, N.Y., USA

    Booth, A. N., Masri, M. S., Robbins, D. J., Emerson, O. H., Jones, F.
         T. & De Eds, F. (1959) J. Biol. Chem., 234, 3014

    Booth, A. N., Robbins, D. J. & De Eds, F. (1961) J. Nutr., 75, 104

    Brun, R. (1970) Dermatologica, 140, 390

              

    a    As sum of dodecyl, octyl, and propyl gallate n-octyl gallate
         should not be used in beverages.

    b    Temporary.

    Buckman, N. D. (1962) Vop. Pitan., 21, 68

    Dacre, J. C. (1960) J. N. Z. Inst. Chem., 24, 161

    Dacre, J. C. (1974) Fd. Cosmet. Toxicol., 12, 125

    Esch, G. J. van (1955) Voeding, 16, 683

    Johnson, A. R. & Hewgill, F. R. (1961) Aust. J. exp. Biol. med. Sci.,
         39, 353

    Lehman, A. J. et al. (1951) Advanc. Food Res., 3, 197

    Lindberg, D. C., Keplinger, M. L. & Fancher, O. E. (1970) Ninety-day
         subacute oral toxicity study with Cold-Pro, GA-8 in Beagle dogs
         (IBT No. C8472). Unpublished report from Industrial Bio-Test
         Labs., Inc., Northbrook, Ill., USA, submitted to the World Health
         Organization by Nutrico, Inc., Milwaukee, Wisconsin, USA

    Olson, W. A. & Voelker, R. W. (1970) Modified two-generation
         reproduction study - Rats. Octyl Gallate. Final report (Project
         458-116). Unpublished report from Hazleton Labs., Inc., Falls
         Church, Va., USA, submitted to the World Health Organization by
         F. & M. Schaefer Brewing Co., Brooklyn, N.Y., USA

    Orten, J. M., Kuyper, A. C. & Smith, A. H. (1948) Food Techn., 2, 308

    Palazzolo, R. J. & Fancher, O. E. (1971a) Human repeated insult patch
         test with n-octyl gallate (IBT No. F9309). Unpublished report
         from Industrial Bio-Test Labs., Inc., Northbrook, Ill., USA,
         submitted to the World Health Organization by Nutrico, Inc.,
         Milwaukee, Wisconsin, USA

    Palazzolo, R. J. & Fancher, O. E. (1971c) Oral mucosa irritation/
         sensitization test with treated beer (IBT No. F9655). Unpublished
         report from Industrial Bio-Test Labs., Inc., Northbrook, Ill.,
         USA, submitted to the World Health Organization by Nutrico, Inc.,
         Milwaukee, Wisconsin, USA

    Palazzolo, R. J. & Fancher, O. E. (1971b) Oral mucosa irritation/
         sensitization test with treated beer (IBT No. F9310). Unpublished
         report from Industrial Bio-Test Labs., Inc., Northbrook, Ill.,
         USA, submitted to the World Health Organization by Nutrico, Inc.,
         Milwaukee, Wisconsin, USA

    Plank, J. B., Wright, P. L., Keplinger, M. L.& Fancher, O. E. (1971)
         Three generation reproduction study with Cold-Pro, GA-8 in albino
         rats (IBT No. P84). Unpublished report from Industrial Bio-Test
         Labs., Inc., Northbrook, Ill., USA, submitted to the World Health
         Organization by Nutrico, Inc., Milwaukee, Wisconsin, USA

    Sluis, K. J. H. van (1951) Food Manuf., 26, 99

    Tollenaar, F. D. (1957) (Pub. 1963) Proc. Pacific Sci. Congr., 5, 92

    Tonkelaar, E. M. den, Verschuuren, H. G., Kroes, R. & Esch, G. J. van
         (1968) Fd. Cosmet. Toxicol., 6, 25

    Weir, R. J. & Brusick, D. (1974) Mutagenic evaluation of Compound FDA
         71-39, Propyl Gallate. Unpublished report from Litton Biomedics,
         Inc., Kensington, Ma., USA, submitted to the World Health
         Organization by the US Food and Drug Administration


    See Also:
       Toxicological Abbreviations