Hazard
Use in foods limited to 0.1%.
Potential Exposure
Sodium benzoate is used as a food and feed additive, flavor, packaging material; pharmaceutical; preservative for food products and tobacco; anti-fungal agent; antiseptic, rust, and mildew inhibitor; intermediate in the manufacture of dyes. Used as a human hygiene biocidal product.
First aid
Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; give artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin. Keep victim warm and quiet. Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed. Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Medical observation is recommended for 24 to 48 hours after breathing overexposure, as pulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consider administering a drug or other inhalation therapy.
Shipping
UN2811 Toxic solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required.
Incompatibilities
Dust may form explosive mixture with air. Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides.
Occurrence
Benzoic acid occurs naturally in many plants and in animals. The salt is not found to occur naturally.
Definition
ChEBI: An organic sodium salt resulting from the replacement of the proton from the carboxy group of benzoic acid by a sodium ion.
Definition
sodium benzoate: An either colourlesscrystalline or white amorphouspowder, C6H5COONa, soluble inwater and slightly soluble in ethanol.It is made by the reaction of sodiumhydroxide with benzoic acid and isused in the dyestuffs industry and asa food preservative. It was formerlyused as an antiseptic.
Preparation
Produced by the neutralization of benzoic acid with sodium bicarbonate, sodium carbonate or sodium hydroxide.
General Description
Sodium benzoate is a sodium salt of benzoic acid, that is freely soluble in water compared to benzoic acid. It is generally used as an antimicrobial preservative in cosmetics, food, and pharmaceuticals.
Pharmaceutical secondary standards for application in quality control, provide pharma laboratories and manufacturers with a convenient and cost-effective alternative to the preparation of in-house working standards.
Flammability and Explosibility
Nonflammable
Pharmaceutical Applications
Sodium benzoate is used primarily as an antimicrobial preservative
in cosmetics, foods, and pharmaceuticals. It is used in concentrations
of 0.02–0.5% in oral medicines, 0.5% in parenteral products,
and 0.1–0.5% in cosmetics. The usefulness of sodium benzoate as a
preservative is limited by its effectiveness over a narrow pH range.
Sodium benzoate is used in preference to benzoic acid in some
circumstances, owing to its greater solubility. However, in some
applications it may impart an unpleasant flavor to a product.
Sodium benzoate has also been used as a tablet lubricant at 2–5%
w/w concentrations. Solutions of sodium benzoate have also been administered, orally or intravenously, in order to determine liver
function.
Biochem/physiol Actions
Sodium benzoate also has pharmaceutical applications and is component of syrup and transparent tablet. High levels of sodium benzoate may trigger histamine release and also induce cell damage. It is recommended for the treatment of urea cycle disorders. However, high levels of sodium benzoate may contribute to glycine deficiency and may impose neuromodulatory effects.
Safety
In combination with ascorbic acid (vitamin C, E300), sodium benzoate and potassium benzoate form benzene, a known carcinogen. However, in most beverages that contain both, the benzene levels are below those considered dangerous for consumption. Heat, light and shelf life can affect the rate at which benzene is formed.
Safety
Ingested sodium benzoate is conjugated with glycine in the liver to
yield hippuric acid, which is excreted in the urine. Symptoms of systemic benzoate toxicity resemble those of salicylates. Whereas
oral administration of the free-acid form may cause severe gastric
irritation, benzoate salts are well tolerated in large quantities: e.g. 6
g of sodium benzoate in 200mL of water is administered orally as a
liver function test.
Clinical data have indicated that sodium benzoate can produce
nonimmunological contact urtcaria and nonimmunological
immediate contact reactions. However, it is also recognized that
these reactions are strictly cutaneous, and sodium benzoate can
therefore be used safely at concentrations up to 5%. However, this
nonimmunological phenomenon should be considered when
designing formulations for infants and children.
Other adverse effects include anaphylaxis and urticarial
reactions, although a controlled study has shown that the incidence
of urticaria in patients given benzoic acid is no greater than that
with a lactose placebo.
It has been recommended that caffeine and sodium benzoate
injection should not be used in neonates; however, sodium
benzoate has been used by others in the treatment of some neonatal
metabolic disorders. It has been suggested that there is a general
adverse effect of benzoate preservatives on the behavior of 3-yearold
children, which is detectable by parents, but not by a simple
clinical assessment.
The WHO acceptable daily intake of total benzoates, calculated
as benzoic acid, has been estimated at up to 5 mg/kg of bodyweight.
LD50 (mouse, IM): 2.3 g/kg
LD50 (mouse, IV): 1.4 g/kg
LD50 (mouse, oral): 1.6 g/kg
LD50 (rabbit, oral): 2.0 g/kg
LD50 (rat, IV): 1.7 mg/kg
LD50 (rat, oral): 4.1 g/kg
storage
Aqueous solutions may be sterilized by autoclaving or filtration. The bulk material should be stored in a well-closed container, in
a cool, dry place.
Properties and Applications
|
TEST ITEMS
|
SPECIFICATION
|
|
APPEARANCE
|
WHITE POWDER
|
|
CONTENT OF SODIUM BENZOATE
|
99.0% min
|
DRY LOSS
|
0.10% max
|
pH VALUE
|
8
|
TOTAL CHLORIDE
|
300 ppm max
|
TRANSPARENCE
|
PASS
|
TOTAL HEAVY METAL
|
0.001% max
|
As CONTENT
|
0.0002% max
|
Purification Methods
Crystallise it from EtOH (12mL/g). [Beilstein 9 IV 27.]
Mechanism of food preservation
The mechanism starts with the absorption of benzoic acid into the cell. If the intracellular pH changes to 5 or lower, the anaerobic fermentation of glucose through phosphofructokinase is decreased by 95 %, thereby inhibiting the growth and survival of micro-organisms that cause food spoilage.
Regulatory Status
GRAS listed. Accepted as a food additive in Europe. Included in the
FDA Inactive Ingredients Database (dental preparations; IM and IV
injections; oral capsules, solutions and tablets; rectal; and topical
preparations). Included in nonparenteral medicines licensed in the
UK. Included in the Canadian List of Acceptable Non-medicinal
Ingredients.
