WORLD HEALTH ORGANIZATION
WHO Food Additives Series 1972, No. 1
TOXICOLOGICAL EVALUATION OF SOME
ENZYMES, MODIFIED STARCHES AND
CERTAIN OTHER SUBSTANCES
The evaluations contained in this publication were prepared by the
Joint FAO/WHO Expert Committee on Food Additives which met in Rome,
16-24 June 19711
World Health Organization
Geneva
1972
1 Fifteenth Report of the Joint FAO/WHO Expert Committee on Food
Additives, Wld Hlth Org. techn. Rep. Ser., 1972, No. 488; FAO
Nutrition Meetings Report Series, 1972, No. 50.
The monographs contained in the present volume are also issued by the
Food and Agriculture Organization of the United Nations, Rome, as FAO
Nutrition Meetings Report Series, No. 50A
(c) FAO and WHO 1972
HYDROXYPROPYL DISTARCH PHOSPHATE
Modification is carried out with 0.1 per cent. phosphorus oxychloride
and 8-10 per cent. of propylene oxide. Cross-linkage would be no
greater than is experienced on modification with phosphorus
oxychloride alone and ether linkages would probably not exceed 20 per
100 anhydroglucose units.
Biological data
Biochemical aspects
Digestibility was tested in groups of 5 rats fed for 7 days a basal
diet supplemented by 0, 1 g and 3 g modified or control starch. No
difference in weight gain was observed (Prier, 1961).
In a caloric utilization study groups of 10 male rats were fed for 10
days either unmodified starch or starch modified with 3 per cent., 6
per cent. or 8 per cent. propylene oxide as well as 0.0123 per cent.
phosphorus oxychloride equivalent to a degree of substitution ranging
from 0.085 to 0.23. There was a slight decrease in caloric
utilization with increasing degree of modification. Diarrhoea
occurred whenever 4 g modified starch was included in the daily ration
but also at the 2 g/day level with the more highly modified starches.
The relative organ weight of the empty caecum was always increased at
the 4 g/day level but also at the 2 g/day level with the 2 highly
modified starches. Histological examination of the heart, liver,
spleen, kidney and caecum revealed no obvious abnormalities related to
treatment. Similar data were obtained in a series of tests using
starches modified in the intermediate range of degree of substitution
by the use of propylene oxide and phosphorus oxychloride (Porter,
1971).
Short-term studies
Rat
Groups of 10 male rats were fed diets containing 17, 34, 51, or 68 per
cent. modified starch for 28 days. Growth and bodyweights were
reduced compared with controls at the two highest levels tested. The
relative organ weights of empty caeca were raised at all levels tested
and the extent of the increase was dose-related. No histological
abnormalities were seen in heart, liver, spleen, kidney and caecum
(Porter, 1971).
Long-term studies
None available.
Comments
Only data from caloric utilization studies are available. Although it
might be feasible to use the data from related modified starches to
arrive at an evaluation there is a need for at least 1 short-term
study at different levels to ensure that no toxicity exists unique to
this modified starch.
EVALUATION
Not possible on the evidence available.
Further work required by 1973
Appropriate 90-day studies in 2 species.
REFERENCES
Porter, M. W. (1971) Unpublished report submitted to WHO by A. E.
Staley Manufacturing Co.
Prier, R. T. (1961) Unpublished report of Wisconsin Alumni Research
Foundation No. 1031347/8, submitted by Stein, Hall & Co., Inc.