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.
GLYCEROL ESTERS OF WOOD ROSIN*
BIOLOGICAL DATA
BIOCHEMICAL ASPECTS
No information.
TOXICOLOGICAL STUDIES
Acute toxicity
LD50 mg/kg bw
Substance Route References
Rats Mice Guinea-pigs
Pale gum Oral 7 600 4 600 4 100 Anonymous, 1974
rosin
Pale wood Oral 8 400 4 100 4 100 " "
rosin
Pale tall Oral 7 600 4 600 4 600 " "
oil rosin
Short-term studies
Rat
(a) Gum rosin
Groups of 10 male and 10 female rats were fed dietary levels of
0.01, 0.05, 0.2, 1.0 and 5.0% for 90 days. Two similar groups received
the stock diet only. No effects were seen upon growth, food intake,
* The natural product rosin is a complex mixture of mutually
soluble organic compounds. There are three general methods of
producing rosins commercially, these methods (and their products)
being: solvent extraction of pure stump wood (wood rosin); tapping of
gum from the living tree (gum rosin); separation from tall oil (tall
oil rosin). The three rosins, freed of extraneous impurities and
refined, differ somewhat quantitatively and in colour but all three
may be glycinerated to produce the glycerol ester.
haematology, urinalysis, gross and microscopic histology at levels
through 0.2%. At the 5% feeding level all animals died. At 1% the test
animals showed an initial lag in weight gain and food consumption
during the first two weeks, and liver size was increased at autopsy,
no microscopic pathology being seen however (Anonymous, 1960a).
(b) Wood rosin
A study was carried out following a protocol similar to that for
gum rosin (see (a) above). Results obtained were similar to those seen
for gum rosin (Anonymous, 1960b)
(c) Tall oil rosin
A study was carried out following a protocol similar to that for
gum rosin (see (a) above). Results obtained were similar for those
seen for gum rosin (Anonymous, 1960c)
(d) Glycerin ester of wood rosin
A study was carried out following a protocol similar to that for
gum rosin (see (a) above) using a Hercules product, Ester Gum 8D. No
effects were noted upon growth, food intake, haematology, urinalysis,
gross and microscopic histology at dietary levels up to and including
1%. At the 5% level depressant effect on growth and food intake was
evident and there was a suggestion of increased liver size. No
microscopic pathology was seen (Anonymous, 1960d).
Long-term studies
Rat
(a) Gum rosin
Groups of 30 male and 30 female rats were fed dietary levels of
0.05, 0.2 and 1.0% for two years. Two similar control groups received
the stock diet only. At the 0.05% and 0.2% feeding levels no effects
were seen upon weight gain, food consumption, mortality, haematology
and gross and microscopic pathology. At the 1% dietary level some
growth depression was noted and at autopsy liver size was increased
although no microscopic pathology was noted (Anonymous, 1962d).
(b) Wood rosin
A study was carried out following a protocol similar to that for
gum rosin (see (a) above). Results obtained were similar to those seen
for gum rosin (Anonymous, 1962e)
(c) Tall oil rosin
A study was carried out following a protocol similar to that for
gum rosin (see (a) above). Results obtained were similar to those seen
for gum rosin (Anonymous, 1962f).
Dogs
(a) Gum rosin
Groups of three male and three female dogs were fed dietary
levels of 0.5 and 1.0 for two years. A control group consisting of six
animals of each sex received the basal diet. At the 0.05% level no
effects were seen upon weight, food consumption, mortality,
haematology, urinalysis, liver and kidney function tests, gross and
microscopic histopathology. At the 1% level some increase in liver and
kidney size was noted although no pathology was present (Anonymous,
1962a).
(b) Wood rosin
A study was carried out following a protocol similar to that for
gum rosin (see (a) above). Results obtained were similar for those
seen for gum rosin (Anonymous, 1960b).
(c) Tall oil rosin
A study was carried out following a protocol similar to that for
gum rosin (see (a) above). Results obtained were similar to those seen
for gum rosin (Anonymous, 1962c).
Comments:
The basic rosins used for production of the glycerol esters are
gum rosin, wood rosin and tall oil rosin. Various modifications of
these rosins are also used for esterification but not included for
evaluation in this monograph. Levels of 0.05%, 0.2%, and 1% in the
diet of all basic rosins have been tested adequately in 90 days and
two year studies in the rat. The effects noted were essentially growth
reduction and increased liver weight without, however, any reported
indication of related histopathology. The no-effect level was 0.2%.
The two year studies in dogs at dietary levels of 0.05 and 1.0% show
that this species reacts in a manner similarly to the rat. In dogs
the effect reported for the 1% level was increased liver weight
accompanying pathology. A 90 days' rat feeding study using a glycerol
ester of wood rosin indicates that this ester is qualitatively similar
in effect to the parent rosin and suggests a lesser degree of
toxicity.
With proper definition of the glycerol ester, the long-term
studies with the parent rosins and the cross-over study with the
glycerol ester of wood rosin would permit an evaluation.
EVALUATION
It was not possible to arrive at an ADI because of absence of a
specification distinguishing glycerol esters of wood rosin from
glycerol esters of other rosins.
REFERENCES
Anonymous (1960a) Unpublished report from Industrial BioTest
Laboratories submitted by Hercules Powder Co.
Anonymous (1960b) Unpublished report from Industrial BioTest
Laboratories submitted by Hercules Powder Co.
Anonymous (1960c) Unpublished report from Industrial BioTest
Laboratories submitted by Hercules Powder Co.
Anonymous (1962a) Unpublished report from Industrial BioTest
Laboratories submitted by Hercules Powder Co.
Anonymous (1962b) Unpublished report from Industrial BioTest
Laboratories submitted by Hercules Powder Co.
Anonymous (1962c) Unpublished report from Industrial BioTest
Laboratories submitted by Hercules Powder Co.
Anonymous (1962d) Unpublished report from Industrial BioTest
Laboratories submitted by Hercules Powder Co.
Anonymous (1962e) Unpublished report from Industrial BioTest
Laboratories submitted by Hercules Powder Co.
Anonymous (1962f) Unpublished report from Industrial BioTest
Laboratories submitted by Hercules Powder Co.
Anonymous (1974) Unpublished report submitted by Hercules Powder Co.