WHO Food Additives Series 1972, No. 1


    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




    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


    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 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 (Kohn & Kay, 1963) or by pancreatin and porcine intestinal
    mucosa (Leegwater, 1971) was somewhat reduced compared with unmodified

    Short-term Studies

    Groups of 10 male and 10 female rats received in their diet 0, 25 and
    50 per cent. of modified starch (0.3 per cent. P) for 8 weeks.  There
    were no detectable adverse effects on body-weight.  Faecal water
    content appeared to be higher in animals fed the 50 per cent. test
    level but the results were too variable to allow any definite
    conclusions.  Production of faeces appeared to be unaffected by this
    modification when compared with controls.  No diarrhoea occurred at
    any test level.  Caecal weight was only slightly increased at the 25
    per cent. level in male rats but there was no consistent effect on
    females at any level tested (de Groot & Spanjers, 1970).


    Groups of 3 male and 3 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 & gay, 1963b).


    Twelve volunteers consumed on each of 4 successive days 60 g of a
    phosphated distarch phosphate with 0.35 per cent. introduced P.  No
    adverse effects were noticed.  No changes occurred as regards
    frequency and amount of faeces of faecal water and lactic acid content
    (Pieters et al., 1971).

    Long-term studies


    Groups of 30 male and 30 female rats were fed a modified starch at
    dietary levels of 0, 5, 10 and 30 per cent. for 104 weeks.  No adverse
    effects were noted on general appearance, behaviour, mortality
    experience or food intake.  Growth rate and food efficiency were
    similar to controls.  Haematology, serum chemistry and urinalysis
    reveal no consistent changes related to the administration of the test
    substance.  Relative organ weights were comparable with controls
    except for significantly decreased spleen weight in males and
    significantly increased spleen and kidney weights in females at the
    highest levels fed.  These changes were not associated with any gross
    pathological findings.  Caecal weights were normal at all test levels.
    There was no obvious evidence of any carcinogenic effect.  The
    histopathological examination has not yet been completed (de
    Knecht-van Eekelen et al., 1971).

    Reproduction studies


    A three generation study was performed using 5 males and 10 females
    for the P generation and 10 males and 20 females of the F1b and F2b
    to produce successive generations by mating at week 12 and 20 after
    weaning.  The F3b generation was kept for 3 weeks after weaning and
    then sacrificed for histopathological study.  The P, F1b and F2b
    parents were used for determination of implantation sites.  The test
    material, fed at 10 per cent. of the diet consisted of starch modified
    with sodium trimetaphosphate up to 0.04 per cent. P and sodium
    tripolyphosphate up to a total of 0.35 per cent. P.  No adverse
    effects were noted regarding appearance, behaviour, mortality,
    body-weights, fertility, litter size, resorption quotient, weaning
    weight of pups or mortality of young.  Caecal weights were increased.
    In the F3b generation spleen weights in females fed this starch
    differed in a statistically significant way from controls.  Gross
    examination at autopsy did not reveal pathological changes
    attributable to ingestion of this starch but histopathology is still
    outstanding (Til et al., 1971).

    Special studies

    Groups of 10 male and 10 female rats were given 0, 25 or 50 per cent.
    modified starch in a low residue diet for 7 days. This was followed by
    3 further days on a diet containing additional 4 per cent. cellulose.
    The body-weights of test animals were slightly reduced in both sexes
    in a dose-related manner but the actual changes were small.  No
    diarrhoea was noted and faecal dry matter was somewhat higher in test
    animals compared with controls.  The addition of cellulose to the diet
    had no adverse effect.  No histological abnormality of the enlarged
    caeca was noted (de Groot & Spanjers, 1970).


    The extent of the modification is small.  The metabolic behaviour of
    the phosphate moieties has not been studied.  The available short-term
    studies in the rat and dog do not reveal any significant adverse
    effects even at high dietary levels, if one accepts the available
    evidence for the group of modified starches considered that caecal
    enlargement without associated histopathological changes is of little
    toxicological significance. The long-term and reproduction studies in
    the rat did not reveal any significant adverse effects and can be used
    for evaluation.


    Temporarily not limited.**

    Further work required by 1973

    Histological reports to complete the long-term and reproduction
    studies in the rat.


    Cervenka, H. & Kay, J. H. (1963) Unpublished report of Industrial
    Biotest Laboratories submitted by Corn Products Co.

    de Groot, A. P. & Spanjers, M. Th. (1970) Unpublished report No. R
    3096 by Centraal Instituut voor Voedingsonderzoek

    de Knecht-van Eekelen, A., Til, H. P., van der Meulen, H. C. & de
    Groot, A. P. (1971) Unpublished report No. R 3392 by Centraal
    Instituut voor Voedingsonderzoek

    Kohn, F. E. & Kay, J. H. (1963) Unpublished report by Industrial
    Biotest Laboratories submitted by Corn Products Co.

    Leegwater, D. C. (1971) Unpublished report No. R 3431 by Centraal
    Instituut voor Voedingsonderzoek

    Pieters, J. J. L., van Staveren, W. A. & Brinkhuis, B. G. A. M. (1971)
    Unpublished report No. R 3433 by Central Instituut voor

    Til, H. P., Spanjers, M. Th. & de Groot, A. P. (1971) Report No. 3403
    of Centraal Instituut voor Voedingsonderzoek

    * Includes distarch phosphate prepared using trimetaphosphate of
    phosphated distarch phosphate or the sum of both. Subject to limits of
    phosphorus load given in the seventh report of the Joint FAO/WHO
    Expert Committee on Food Additives, Wld Hlth Org. techn. Rep. Ser.,
    281, p. 31
    ** Except for good manufacturing practice.

    See Also:
       Toxicological Abbreviations
       Phosphated distarch phosphate  (FAO Nutrition Meetings Report Series 46a)
       Phosphated distarch phosphate (WHO Food Additives Series 5)
       Phosphated distarch phosphate (WHO Food Additives Series 17)