WHO Food Additives Series, 1972, No. 4
EVALUATION OF MERCURY, LEAD, CADMIUM
AND THE FOOD ADDITIVES AMARANTH,
DIETHYLPYROCARBONATE, AND OCTYL GALLATE
The evaluations contained in this publication were prepared by the
Joint FAO/WHO Expert Committee on Food Additives which met in Geneva,
4-12 April 19721
World Health Organization
Geneva
1972
1 Sixteenth Report of the Joint FAO/WHO Expert Committee on Food
Additives, Wld Hlth Org. techn. Rep. Ser., 1972, No. 505; FAO
Nutrition Meetings Report Series, 1972, No. 51.
n-OCTYL GALLATE
Propyl, octyl and dodecyl gallates have previously been evaluated in
the Sixth and Eighth Report of the Joint FAO/WHO Expert Committee.
Additional Biological Data
Acute toxicity
Animal Route LD50 Vehicle Reference
(Mg/kg body wt.)
Rat (male) oral 2710 corn oil Brun, 1970
Rat (female) " 1960 " "
Rat (male) " 2710 water "
Rat (female) " 2330 " "
Short-term studies
Rat
Groups each of 20 rats (equally divided by sex) were maintained on
diets containing 0, 1000, 2500 and 5000 ppm 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 (Hazleton Lab. Inc. 1969a).
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, then reduced to 0.6% for the remainder 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 (Industrial Biotest Lab., 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 (Hazleton Lab. Inc. 1969b).
Long-term studies
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 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 offsprings. At 0.3 and 0.6% dietary
octyl gallate, there was no significant effect on the rat foetuses
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 offsprings through weaning (Industrial Biotest Lab., 1970).
Groups each of 10 male and 20 female rats were maintained on diets
containing 0, 1000 or 5000 ppm 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
level was replaced by a 2500 ppm 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 lutes and
foetuses determined. One half 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 group 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 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. At the 1000 ppm, 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 foetuses.
Necropsy of the pups indicated a higher incidence of gross kidney
alterations than that observed in controls. No compound-related
histology was reported. (Hazleton Lab. Inc. 1970).
Special studies
Dermatological effects
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
(Industrial Biotest Lab., 1971). Oral mucosa irritation/sensitization
tests were conducted with beer containing 20 ppm 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 (Industrial Biotest Lab., 1971).
EVALUATION
Reproduction studies in the rat show that the mortality of suckled
young observed at the highest levels were due to a perinatal effect,
and must have been caused by a factor entering the mother's milk. It
has not been established if the reported decrease in implantation
sites and number of corpora lutea, that occurred at the third breeding
of the P2 parents is due to an effect on viability of ova or sperm.
The "no-effect" level in rats, based on reproduction studies is 1000
ppm (0.1%) of the diet, i.e. 100 mg/kg body-weight/day.
n-Octyl gallate can cause reactions indicative of sensitization in the
buccal mucosa of individuals previously sensitized by cutaneous
contact with the gallate ester. Because of this observation the use
of n-octyl gallate in beer or other beverages consumed in large
amounts is not acceptable.
Those occupationally exposed to gallate esters should be made aware of
the sensitizing potential of these substances.
REFERENCES
Brun, R. (1970) Dermatologica, 140, 390
Hazleton Lab. Inc. (1969a) Unpublished report. Project No. 458-117
Hazleton Lab. Inc. (1969b) Unpublished report. Project No. 458-115
Hazleton Lab. Inc. (1970) Unpublished report. Project No. 458-116
Industrial Biotest Lab. (1970) Unpublished report. IBT No. C8472
Industrial Biotest Lab. (1971) Unpublished reports. IBT No. P8473;
IBT No. 8473; IBT No. F9655
See Also:
Toxicological Abbreviations