Sodium benzoate is a salt of benzoic acid that is found naturally in cranberries, prunes, plums, apples, and other fruits. As a preservative, sodium benzoate is primarily an anti-fungal agent but also has some effectiveness against bacteria. The U.S. Food and Drug Administration (FDA) has designated it a “generally recognized as safe” ingredient.

Related Reading:
https://online.personalcarecouncil.org/jsp/CIRList.jsp?id=2130

Benzyl alcohol, benzoic acid, sodium benzoate, and potassium benzoate. According to the OECD SIDS initial assessment report on benzoates, benzoic acid and benzyl alcohol were slightly irritating to the skin, whereas sodium benzoate was nonirritating.3

The following cosmetic ingredients are reviewed in this safety assessment: benzyl alcohol, benzoic acid, sodium benzoate, calcium benzoate, magnesium benzoate, potassium benzoate, and benzyl benzoate. Most of these ingredients function as fragrance ingredients/preservatives in cosmetic products. Together, data reported to the FDA VCRP in 2010 and the results of a 2010 industry survey performed by the council indicated use of the following ingredients in cosmetics: benzyl alcohol, benzoic acid, sodium benzoate, calcium benzoate, potassium benzoate, and benzyl benzoate. According to this industry survey, ingredient use concentrations have ranged from 0.000001% (sodium benzoate) to 5% in leave-on products (benzoic acid) and 10% in rinse-off products (benzyl alcohol).

Sodium benzoate (Wikipedia)

Sodium benzoate is the sodium salt of benzoic acid, widely used as a food preservative (with an E number of E211) and a pickling agent. It appears as a white crystalline chemical with the formula C₆H₅COONa.

Sodium benzoate

Skeletal formula
Ball-and-stick model of part of the crystal structure
Ball-and-stick model of packing in the crystal structure
Names
Preferred IUPAC name Sodium benzoate
Other names E211, benzoate of soda
Identifiers
CAS Number	532-32-1 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:113455 Y
ChEMBL	ChEMBL1356 Y
ChemSpider	10305 Y
ECHA InfoCard	100.007.760
E number	E211 (preservatives)
PubChem CID	517055
RTECS number	DH6650000
UNII	OJ245FE5EU Y
CompTox Dashboard (EPA)	DTXSID1020140
InChI InChI=1S/C7H6O2.Na/c8-7(9)6-4-2-1-3-5-6;/h1-5H,(H,8,9);/q;+1/p-1 Y Key: WXMKPNITSTVMEF-UHFFFAOYSA-M Y InChI=1/C7H6O2.Na/c8-7(9)6-4-2-1-3-5-6;/h1-5H,(H,8,9);/q;+1/p-1 Key: WXMKPNITSTVMEF-REWHXWOFAY
SMILES [Na+].[O-]C(=O)c1ccccc1
Properties
Chemical formula	C7H5NaO2
Molar mass	144.105 g·mol−1
Appearance	white or colorless crystalline powder
Odor	odorless
Density	1.497 g/cm3
Melting point	410 °C (770 °F; 683 K)
Solubility in water	62.65 g/100 mL (0 °C) 62.84 g/100 mL (15 °C) 62.87 g/100 mL (30 °C) 74.2 g/100 mL (100 °C)
Solubility	soluble in liquid ammonia, pyridine
Solubility in methanol	8.22 g/100 g (15 °C) 7.55 g/100 g (66.2 °C)
Solubility in ethanol	2.3 g/100 g (25 °C) 8.3 g/100 g (78 °C)
Solubility in 1,4-Dioxane	0.818 mg/kg (25 °C)
Pharmacology
ATC code	A16AX11 (WHO)
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H319
Precautionary statements	P305+P351+P338
NFPA 704 (fire diamond)	2 1 0
Flash point	100 °C (212 °F; 373 K)
Autoignition temperature	500 °C (932 °F; 773 K)
Lethal dose or concentration (LD, LC):
LD50 (median dose)	4100 mg/kg (oral, rat)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references