INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
WORLD HEALTH ORGANIZATION
TOXICOLOGICAL EVALUATION OF SOME
FOOD COLOURS, EMULSIFIERS, STABILIZERS,
ANTI-CAKING AGENTS AND CERTAIN
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.
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
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).
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.
Level causing no toxicological effect in the rat
Five per cent. (= 50 000 ppm) in the diet equivalent to 2500 mg/kg
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
Industrial Bio-Test Laboratories (1962) Unpublished report to Hercules
Industrial Bio-Test Laboratories (1963) Unpublished report to Hercules
Industrial Bio-Test Laboratories (1964) Unpublished report to Hercules
1 As sum of total cellulose derivatives (see tenth report of the
Joint FAO/ WHO Expert Committee on Food Additives, Ref 13 Annex 1).