EDTA

Ethylenediaminetetraacetic acid

Disodium EDTA
Names
Systematic IUPAC name 2,2',2'',2'''-(Ethane-1,2-diyldinitrilo)tetraacetic acid
Other names N,N'-Ethane-1,2-diylbis[N-( carboxymethyl)glycine] Fiaminoethane-tetraacetic acid Edetic acid (conjugate base edetate) (INN, USAN) Ethylenedinitrilo-tetraacetic acid Versene
Identifiers
CAS Number	60-00-4 Y
3D model (Jmol)	Interactive image
Abbreviations	EDTA, H4EDTA
Beilstein Reference	1716295
ChEBI	CHEBI:42191 Y
ChEMBL	ChEMBL858 Y
ChemSpider	5826 Y
DrugBank	DB00974 Y
ECHA InfoCard	100.000.482
EC Number	200-449-4
Gmelin Reference	144943
KEGG	D00052 Y
MeSH	Edetic+Acid
PubChem	6049
RTECS number	AH4025000
UNII	9G34HU7RV0 Y
UN number	3077
InChI InChI=1S/C10H16N2O8/c13-7(14)3-11(4-8(15)16)1-2-12(5-9(17)18)6-10(19)20/h1-6H2,(H,13,14)(H,15,16)(H,17,18)(H,19,20) Y Key: KCXVZYZYPLLWCC-UHFFFAOYSA-N Y
SMILES OC(=O)CN(CCN(CC(O)=O)CC(O)=O)CC(O)=O
Properties
Chemical formula	C10H16N2O8
Molar mass	292.24 g·mol−1
Appearance	Colourless crystals
Density	860 mg mL−1 (at 20 °C)
log P	−0.836
Acidity (pKa)	1.782
Basicity (pKb)	12.215
Thermochemistry
Std enthalpy of formation (ΔfHo298)	−1.7654 to −1.7580 MJ mol−1
Std enthalpy of combustion (ΔcHo298)	−4.4617 to −4.4545 MJ mol−1
Pharmacology
ATC code	S01XA05 (WHO) V03AB03 (WHO) (salt)
Routes of administration	Intramuscular Intravenous
Hazards
GHS pictograms
GHS signal word	WARNING
GHS hazard statements	H319
GHS precautionary statements	P305+351+338
EU classification (DSD)	Xi
R-phrases	R36
S-phrases	(S2), S26
NFPA 704	0 1 0
Lethal dose or concentration (LD, LC):
LD50 (median dose)	1000 mg/kg (oral, rat)
Related compounds
Related alkanoic acids	Daminozide Octopine
Related compounds	Triethylenetetramine Tetraacetylethylenediamine PMDTA Bis-tris propane
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Ethylenediaminetetraacetic acid (EDTA), also known by several other names, is a chemical used for both industrial and medical purposes.

It is an aminopolycarboxylic acid and a colourless, water-soluble solid. Its conjugate base is ethylenediaminetetraacetate. It is widely used to dissolve limescale. Its usefulness arises because of its role as a hexadentate ("six-toothed") ligand and chelating agent, i.e., its ability to "sequester" metal ions such as Ca²⁺ and Fe³⁺. After being bound by EDTA into a metal complex, metal ions remain in solution but exhibit diminished reactivity. EDTA is produced as several salts, notably disodium EDTA and calcium disodium EDTA.

In industry, EDTA is mainly used to sequester metal ions in aqueous solution. In the textile industry, it prevents metal ion impurities from modifying colors of dyed products. In the pulp and paper industry, EDTA inhibits the ability of metal ions, especially Mn²⁺, from catalyzing the disproportionation of hydrogen peroxide, which is used in "chlorine-free bleaching". In a similar manner, EDTA is added to some food as a preservative or stabilizer to prevent catalytic oxidative decoloration, which is catalyzed by metal ions. In soft drinks containing ascorbic acid and sodium benzoate, EDTA mitigates formation of benzene (a carcinogen).

The reduction of water hardness in laundry applications and the dissolution of scale in boilers both rely on EDTA and related complexants to bind Ca²⁺, Mg²⁺, as well as other metal ions. Once bound to EDTA, these metal centers tend not to form precipitates or to interfere with the action of the soaps and detergents. For similar reasons, cleaning solutions often contain EDTA.