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.


    HYDROXYPROPYL CELLULOSE

    Biological Data

    Biochemical aspects

    14C-labelled hydroxypropyl cellulose was administered to four rats
    in a five per cent. aqueous solution. One male and one female rat
    received 0.25 g/kg body weight, the other two rats received 1 g/kg
    body weight. Urine, faeces and expired air were collected over the
    next 120 h. Then all organs were assayed for residual radioactivity.
    No activity (< 0.01 per cent. of the administered dose) was detected
    in organs, urine and expired air due to administered material.
    Recoveries of activity in the faeces varies from 98.32 to 102.7 per
    cent. Hence orally ingested material is not absorbed from the
    gastro-intestinal tract of the rat and is excreted quantitatively in
    the faeces principally in the first 48 h.

    To check on enterohepatic circulation two additional rats with ligated
    bile ducts were administered 1 g/kg of radio-labelled material. Bile
    was collected for 72 h but no significant activity was found
    (Industrial Bio-Test Lab., 1964).

    Acute oral toxicity

                                                                     

    Animal    Route          LD50           Reference
                        mg/kg body weight
                                                                     

    Rat       Oral           10 200         Industrial Bio-Test 
                                            Lab., 1962
                                                                     

    Short-term studies

    Rat. Groups of five male and five female rats received in their diet
    0.2 per cent., 1.0 per cent. and 5.0 per cent, of hydroxypropyl
    cellulose for 90 days. Controls received unmodified cellulose at the
    same levels. There were no differences observed between tests and
    controls as regards mortality, growth, food utilization, urinalysis,
    haemotological indices, organ weight, gross pathology and
    histopathology. At higher dietary levels there was increased food
    consumption and decreased food utilization consequential to the
    inertness of the material (Industrial Bio-Test Lab., 1963).

    Long-term studies

    None available.

    Comments

    The metabolic study has revealed adequate in vivo evidence of the
    biochemical inertness of hydroxypropyl cellulose and of its
    non-absorption during passage through the gastro-intestinal tract.
    This behaviour parallels that of other modified celluloses considered
    previously. The material studied had the highest dense of
    hydroxypropyl substitution likely to be used as food additive.
    Long-term studies are therefore not necessary.

    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

                                            mg/kg body weight

    Unconditional acceptance                    0-301

    Conditional acceptance                  Higher levels for dietetic and
                                            calory control purposes

    REFERENCES

    Industrial Bio-Test Laboratories (1962) Unpublished report to Hercules
    Powder Co.

    Industrial Bio-Test Laboratories (1963) Unpublished report to Hercules
    Powder Co.

    Industrial Bio-Test Laboratories (1964) Unpublished report to Hercules
    Powder Co.



                   

    1 As sum of total cellulose derivatives (see tenth report of the
    Joint FAO/ WHO Expert Committee on Food Additives, Ref 13 Annex 1).
    

    See Also:
       Toxicological Abbreviations
       HYDROXYPROPYL CELLULOSE (JECFA Evaluation)