WHO/Food Add./24.65
FAO Nutrition Meetings
Report Series No. 38A
SPECIFICATIONS FOR IDENTITY AND
PURITY AND TOXICOLOGICAL EVALUATION
OF SOME ANTIMICROBIALS AND
ANTIOXIDANTS
The content of this document is the result of the deliberations of the
Joint FAO/WHO Expert Committee on Food Additives which met 8-17
December 1964a
a Eighth Report of the Joint FAO/WHO Expert Committee on Food
Additives, Wld Hlth Org. techn. Rep. Ser., 1965, 309; FAO
Nutrition Meetings Report Series 1965, 38.
TARTARIC ACID
CHEMICAL NAMES Tartaric acid; 2,3-dihydroxysuccinic acid
EMPIRICAL FORMULA C4H6O6
STRUCTURAL FORMULA HOOC - CHOH - CHOH - COOH
MOLECULAR WEIGHT 150.09
DEFINITION Tartaric acid contains not less than 99.5% of
C4H6O6 after drying to constant weight at
105°C.
DESCRIPTION A colourless or translucent, odourless,
crystalline solid with an acid taste. 1 g is
soluble in 0.8 ml of water or 3 ml of ethanol.
NATURAL OCCURRENCE Tartaric acid occurs in many fruits, either
free or combined with potassium, calcium or
magnesium. It may constitute from 60-80% of
the non-volatile acid in wine.
USE As a synergist with antioxidants and as an
acidic constituent in some baking powders.
Biological Data
Biochemical aspects
Tartaric acid is metabolically inert in the human body.1,2,3,4 When
taken by mouth, only about 20% of ingested tartrate is eliminated in
the urine; the reminder is not absorbed but destroyed in the
intestinal tract by bacterial action.
Acute toxicity
In the mouse, the LD50 of the sodium salt administered by mouth was
found to be 4360 mg/kg body-weight.5
Tartaric acid administered by stomach tube in a dose of 5000 mg/kg was
fatal to a dog.6
Three out of 7 male rabbits died following oral administration of
disodium tartrate in an average dose of 5290 mg/kg; while 6 male
rabbits survived an average oral dose of 3680 mg/kg.5
Short-term studies
Rabbit. Three rabbits survived 17 consecutive daily feedings of
disodium tartrate in an average dosage of 1150 mg/kg; whereas average
dosages of 3680 mg/kg killed 3 out of 6 rabbits in 6 to 19 consecutive
daily feedings.5
Dog. Tartaric acid was administered in daily oral doses of 990
mg/kg to each of 4 dogs for 90-114 days. Casts appeared in the urine
of 3 dogs; the blood chemistry remained normal except in 1 dog in
which azotaemia developed with death in 90 days. Weight changes
varied from a gain of 30% to a loss of 32%.7
Long-term studies
Rat. Groups of 24 rats (12 of each sex) were fed diets containing
0.1%, 0.5%, 0.8% and 1.2% of tartaric acid for a period of 2 years. A
group of 48 rats served as controls. No significant toxic effects
were observed in any of the groups as determined by growth rate (for
the first year), mortality throughout the experiment, and gross and
microscopic findings at the end of the 2-year, period. An
exceptionally thorough microscopic pathological examination was
carried out.8
Comments on experimental studies reported
In the Seventh Report of the Joint FAO/WHO Expert Committee on Food
Additives (page 63), evaluations of sodium tartrate and potassium
sodium tartrate are presented with the comment that the evaluation of
tartaric acid in the Sixth Report may have been unduly restrictive in
comparison with that of the tartrates. The present re-evaluation is
made after reconsideration of the data used previously in the light of
this comment.
Evaluation
Level causing no significant toxicological effect in the rat
1.2% (= 12 000 ppm) in the diet, equivalent to 600 mg/kg body-weight
per day.
Estimate of acceptable daily intakes for man
The total daily intake of tartrate should not exceed:
mg/kg body-weight
Unconditional acceptance 0-6
Conditional acceptance 6-20
References
1. Underhill, F. P., Peterman, F. I. & Krause, A. G. (1931) J.
Pharmacol. exp. Ther., 43, 351
2. Underhill, F. P., Leonard, C. S., Gross, E. G. & Joleski, T. C.
(1931) J. Pharmacol. exp. Ther., 43, 359
3. Underhill. F. P., Peterman, F. I., JoleskI, T. C. & Leonard, C. S.
(1931) J. Pharmacol. exp. Ther., 43, 381
4. Finkle, P. (1933) J. biol. Chem., 100, 349
5. Locke, A., Locke, R. B., Schlesinger, H. & Carr, H. (1942) J.
Amer. pharm. Ass., sci. Ed., 31, 12
6. Sourkes, T. L. & Koppanyi, T. (1950) J. Amer. pharm. Ass., sci.
Ed., 34, 275
7. Krop, S. & Gold, H. (1945) J. Amer. pharm. Ass., sci. Ed., 34, 86
8. Fitzhugh, O. G. & Nelson, A. A. (1947) J. Amer. pharm. Ass., sci.
Ed., 36, 217