INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
WORLD HEALTH ORGANIZATION
TOXICOLOGICAL EVALUATION OF SOME
FOOD COLOURS, EMULSIFIERS, STABILIZERS,
ANTI-CAKING AGENTS AND CERTAIN
OTHER SUBSTANCES
FAO Nutrition Meetings Report Series
No. 46A WHO/FOOD ADD/70.36
The content of this document is the result of the deliberations of the
Joint FAO/WHO Expert Committee on Food Additives which met in Rome,
27 May - 4 June 19691
Food and Agriculture Organization of the United Nations
World Health Organization
1 Thirteenth 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.
PHOSPHATED DISTARCH PHOSPHATE
Biological Data
These modified starches are prepared by the combined use of sodium
tripolyphosphate and sodium trimetaphosphate which results in
cross-linking and esterification of starch chains. The overall extent
of modification is still small, the residual phosphate being of the
order of 0.4 per cent. P.
Biochemical aspects
The in vitro digestibility of this modified starch by pancreatic
amylase was somewhat reduced compared with normal unmodified starch
(Kohn & Kay 1963a). In vivo digestibility was examined in groups of
10 male rats fed for 10 days 5 g basal diet supplemented by 1 g, 2 g,
or 4 g unmodified or modified starch. Weight gains were identical for
both types tested at all three levels of supplementation. No unusual
behavioural reactions were observed (Kohn & Kay 1963b).
Acute toxicity
None available.
Short-term studies
Rat. Groups of 10 male and 10 female rats were fed on a diet
containing 10 per cent. rising to 35 per cent. of phosphated distarch
phosphate for a total of 60 days. Female rats showed a consistent
reduced weight gain throughout the test. Although four test and two
control animals died during the test these incidents were regarded as
unrelated to the test substance. All animals behaved normally.
Haematological examination and urinalysis were normal and comparable
in the various groups. The absolute liver weights of male rats were
lower for the test group than for controls and the absolute kidney
weight were lower for both sexes but these findings were not
associated with any gross or histopathological changes. (Kohn et al.,
1964).
Groups of 25 male and 25 female rats were fed diets containing 0.2 per
cent., 1.0 per cent. and 5.0 per cent. modified or unmodified starch
for 90 days. Eleven controls and three test animals died from
intercurrent disease. There were no obvious gross or histopathological
changes attributable to the test substance. Organ weights and
haematological examination (days 45 and 90) were normal in both
groups. Pooled urinalysis was comparable for all three groups. (Kohn
et al., 1964).
Dog. Groups of three male and three female beagles were given daily
for 90 days gelatine capsules containing 50, 250 and 1250 mg modified
starch/kg body weight. No adverse effects were observed as judged by
behaviour, body weight changes, mortality, haematological studies,
blood chemistry, urinalysis, liver function tests, organ weights,
gross and histopathological findings (Cervenka & Kay, 1963b).
Long-term studies
None available.
Comments
Although the extent of the modification is small there is some
evidence of reduced in vitro digestibility by enzymes. The levels
tested in rats and dogs represent 3.5 per cent. - 5 per cent. of the
diet and did not attain an effect level. Further metabolic studies
preferably in man are desirable. Evaluation is based on the available
short-term studies but further 90-day studies in two species at levels
higher than those studied hitherto are desirable.
EVALUATION
Level causing no toxicological effect in the rat
Five per cent. (= 50 000 ppm) in the diet equivalent to 2500 mg/kg
body weight/day.
Estimate of acceptable daily intake for man
Unconditional acceptance mg/kg body weight
0 - 25a
REFERENCES
Cervenka, H. & Kay, J, H. (1963) Unpublished reportb submitted by
Corn Products Co.
Kohn F. E. & Kay, J. H. (1963a) Unpublished reportb submitted by
Corn Products Co.
Kohn, F. E. & Kay, J. H. (1963b) Unpublished reportb submitted by
Corn Products Co.
Kohn, F. E. Kay, J. H. & Calandra, J. C. (1964a) Unpublished reportb
submitted by Corn Products Co.
Kohn, F. E. & Kay, J. H. (1964b) Unpublished reportb submitted by
Corn Products Co.
a Includes distarch phosphate prepared using trimetaphosphate or
phosphated distarch phosphate or the sum of both. Subject to limits of
phosphorous load given in the seventh report of the Joint FAO/WHO
Expert Committee on Food Additives, Wld. HIth Org. techn. Rep. Ser.,
281, p.31.
b By Industrial Bio-test Laboratories.