Calcium disodium EDTA
(synthetic chelating/sequestering agent; food additive E385)

Description

• Calcium–disodium salt of EDTA (ethylenediaminetetraacetic acid), a polyamino-carboxylic chelating agent able to bind multivalent metal ions.

• Appears as a white crystalline powder, practically odourless, with a slightly salty–metallic taste.

• In foods it is used as a metal chelator/sequestrant, with an indirect antioxidant effect, stabilising colour, flavour and, to some extent, texture in various packaged products.

Key constituents

• The active substance is calcium disodium EDTA itself:

  • four carboxylate groups and two chelating nitrogen atoms → strong affinity for metal ions such as Fe³⁺, Cu²⁺, Zn²⁺, Ca²⁺, Mg²⁺ and others;

  • forms very stable complexes, reducing the availability of these metals for oxidation reactions and for some unwanted enzymatic reactions.

• Trace levels of other EDTA salts and synthesis by-products may be present within defined purity limits.

Production process

• Industrial synthesis of EDTA from ethylenediamine, formaldehyde and cyanide-derived intermediates, forming sodium salts as intermediates.

• Conversion to free EDTA acid and subsequent neutralisation with sodium and calcium bases to obtain the calcium–disodium salt at controlled stoichiometric ratio.

• Final steps: crystallisation, filtration, drying, milling, and packing into suitable food-grade containers.

Physical properties

• Appearance: white crystalline powder.

• Odour: practically odourless.

• Taste: slightly salty–metallic (perceptible only at high doses).

• Solubility: freely soluble in water, insoluble in fats/oils.

• Aqueous solution pH: generally slightly acidic to near neutral, depending on concentration.

• Thermally stable under typical food processing conditions.

Sensory and technological properties

• Metal chelation:

  • binds iron, copper and other transition metals that catalyse oxidation of lipids, pigments (e.g. carotenoids, chlorophylls) and sensitive vitamins;

  • reduces rancidity, browning, colour loss and development of oxidised off-flavours.

• At normal use levels, impact on taste is minimal; overdosing can produce metallic notes.

• Improves colour and flavour stability in products fortified with vitamins or sensitive to trace metals in water or raw materials.

Food applications

As food additive E385 – calcium disodium EDTA, used within legal limits in:

• Canned and preserved foods: vegetables, pulses, fish (e.g. tuna) to stabilise colour and flavour and limit darkening.

• Sauces and dressings: mayonnaise, creamy dressings, oil-rich sauces where it helps prevent oxidation of fats and pigments and supports emulsion stability.

• Soft drinks and juices: helps preserve colour and flavour and can reduce haze linked to metals and colloidal instability.

• Other products: margarines and spreads, ready salads, certain preserves, when allowed by regulation.

(It is also used in medicines and non-food sectors)

Nutrition & health

• Poor oral absorption: most ingested calcium disodium EDTA is not absorbed and is excreted in faeces; the small absorbed fraction is excreted in urine as metal complexes.

• Major food-safety authorities consider calcium disodium EDTA safe at authorised food-use levels, with an ADI (acceptable daily intake) set in the low mg/kg body weight/day range.

• At doses far above food-use levels (pharmacological or experimental exposures) effects on mineral metabolism have been reported; ADI limits are therefore set conservatively.

• It does not provide fats (SFA, MUFA, PUFA) or other nutrients of interest: its role is purely technological, not nutritional.

Serving note: at typical concentrations (tens to a few hundred mg/kg, depending on category), normal dietary exposure generally remains below the ADI for most consumers when legal limits are respected.

Allergens and intolerances

• Calcium disodium EDTA is not a major allergen and contains no proteins related to the 14 mandatory EU allergens.

• Hypersensitivity reactions are considered rare, but may occur in particularly sensitive individuals to chelating agents or specific formulations.

• In foods, the main allergens almost always originate from other ingredients (milk, gluten, soy, egg, etc.), not from E385 itself.

Quality and specifications (typical contract parameters)

• Identity and purity:

  • assay for calcium disodium EDTA within defined range;

  • limits for heavy metals (lead, mercury, cadmium, arsenic);

  • checks on pH of standard solutions and identification tests.

• Appearance: white powder, free from hard lumps and foreign odours.

• Microbiology: as a dry salt it has very low water activity; microbiological requirements mainly concern the finished foods into which it is incorporated.

Storage and shelf-life

• Store in a cool, dry, well-ventilated place, protected from moisture and contamination.

• Keep containers tightly closed; avoid prolonged contact with bare reactive metals.

• Typical raw-material shelf-life: 2–5 years depending on manufacturer’s specification and storage conditions.

Safety and regulatory

• In Europe it is authorised as additive E385 in specific food categories, with maximum permitted levels expressed in mg/kg of finished product.

• Production must follow GMP and HACCP, with batch traceability and control of raw materials and impurities.

• International agencies have evaluated its toxicological profile and defined ADI and authorised food categories and levels.

Labeling

• In ingredient lists it may appear as:

  • “E385” with its technological function (e.g. “sequestrant”, “antioxidant”, “preservative”, according to local classification), or

  • “calcium disodium EDTA” in full text.

• For non-EU markets, local labelling rules apply (e.g. specific FDA naming).

Troubleshooting (technological use)

• Metallic or off-taste

  • Possible cause: excessive dosage or interaction with other salts/ingredients.

  • Action: reduce use level, rebalance the formula or combine with other antioxidant systems.

• Insufficient protection against oxidation (rancidity/browning still evident)

  • Possible causes: dose too low relative to metal load, poor water quality, non-optimal pH, highly sensitive product.

  • Action: check metal levels, consider combining with primary antioxidants (e.g. ascorbates, tocopherols), optimise pH and overall antioxidant system.

• Analytical interference in metal determination

  • EDTA complexes can mask metals and affect analytical quantification.

  • Action: use digestion/analytical conditions that release metals from complexes.

Sustainability and supply chain

• EDTA is a chelating agent with limited biodegradability, so it is of environmental interest particularly in wastewater, detergents and industrial uses.

• In food applications the quantitative contribution is relatively small, but it is still important to manage industrial effluents with appropriate treatment and to optimise water and energy use.

• In some non-food uses, more easily biodegradable alternative chelators are being explored; in foods, authorised uses and limits must be followed.

Main INCI functions (cosmetics)

• Related INCI names: Calcium Disodium EDTA, Disodium EDTA, Tetrasodium EDTA, etc.

• Functions: chelating agent, formulation stabiliser (helps maintain preservative, colour and fragrance performance in the presence of metals).

• Cosmetic use is also limited to low concentrations, with environmental and safety aspects taken into account.

Conclusion

Calcium disodium EDTA (E385) is a synthetic chelating/sequestering agent used in foods to bind metal ions, improving oxidative stability, maintaining colour and flavour, and supporting shelf-life of canned products, sauces, beverages and other metal-sensitive foods. At authorised levels, its nutritional impact is essentially zero while its technological benefit can be significant. Proper use requires respect of legal limits, integration into the HACCP plan, and responsible management of effluents to keep consumer and environmental risk under control.

Mini-glossary

• Chelating/sequestering agent – Molecule able to bind metal ions in stable complexes, removing them from unwanted reactions (oxidation, catalysis).

• EDTA – Ethylenediaminetetraacetic acid, synthetic chelating agent forming the basis of several salts (disodium, calcium–disodium, etc.).

• E385 – European code for the additive “calcium disodium EDTA”.

• ADI (acceptable daily intake) – Daily intake level (mg/kg body weight) considered safe for chronic exposure.

• GMP/HACCP – Good Manufacturing Practices / Hazard Analysis and Critical Control Points; core systems to ensure hygiene, traceability and risk control.

• BOD/COD – Biochemical/Chemical Oxygen Demand; indicators of organic load and oxygen demand in wastewater, relevant for environmental management.

Studies

In chemistry, it is a six-atom complexation agent that regulates the equilibrium between ligand and metal ions, often added to lysate with magnesium and calcium complex ions to stabilise nucleic acid and degrade nuclease activity. It controls the polymerisation rate. It also functions as a chelating agent, i.e. an agent that binds to another to promote elimination or harmful reactions caused by metal ions and to form a stable water-soluble complex. These studies explain the mechanism (1).  It can chelate with a large majority of different metal ions other than alkali metals such as calcium, magnesium, iron, copper and other polyvalent ions.

It also works as a descaler (2) and as an antioxidant method also called the Fenton method (3).

Widely used to prevent oxidation caused by metals.

Food

Labelled with the number E385 in the list of European food additives, Disodium EDTA is a chemical compound that is added to food as a preservative and chelating agent to prevent spoilage of the product in which it is included and to counteract other ingredients.

It is found in carbonated drinks, jellies, canned beans, mayonnaise and others.

To check for its presence in food, a convenient HPLC method was developed for the quantitative determination of EDTA in food. EDTA in food samples was easily extracted with water using ultrasound. After conversion to Fe (III) complex in the presence of Fe (III) ions, EDTA was separated on a reversed-phase C30 column and detected by ultraviolet detection (260 nm). Citrate and malate, which are present in many foods, also formed Fe (III) complexes but did not interfere with the chromatographic detection of EDTA. The method allowed the determination of EDTA in food at concentrations down to 0.01 mmol/kg. Good recoveries (95.2-101%) were obtained with the standard addition method on four samples with high repeatability (RSD, 0.8-3.4%). The method was successfully applied to the analysis of EDTA in carbonated drinks, jellies, canned beans, canned maize and food supplements (4). 

Disodium EDTA is a known enhancer of iron absorption, yet the results of this study suggest that in the presence of EDTA, iron absorption occurs mainly from the paracellular rather than the regulated cellular mode, which could potentially increase its toxicity (5).

There is a maximum ADI (Acceptable Daily Intake) or GDA (Acceptable Daily Allowance) of 2.5 grams per kg body weight for this food additive (6).

Cosmetics

It acts as a chelating agent and pH adjuster in cosmetic formulations. Chelating agents are known to be cytotoxic and weakly genotoxic, but not carcinogenic as confirmed by the final report of the Expert Panel for the Review of Cosmetic Ingredients (7).

Chelating agent. It has the function of preventing unstable reactions and improving the bioavailability of chemical components within a product, and removes calcium and magnesium cations that can cause cloudiness in clear liquids.

Viscosity control agent. It controls and adapts viscosity to the required level for optimal chemical and physical stability of the product and dosage in gels, suspensions, emulsions, solutions. 

Medical

Disodium EDTA is used in the form of intravenous administration in chelation therapy for lead and heavy metal poisoning, in the treatment of calcified tendonitis, as an anticoagulant and bactericide due to its low cost.

Other uses

• additive, bleaching and fixing agent for processing colour-sensitive materials
• water purifier and cleaner
• agricultural chemicals
• plant growth inhibitor
• chemical plating, cyanide-free electroplating

For more information:

Disodium EDTA studies

Typical commercial product characteristics Ethylenediaminetetraacetic acid disodium salt

Appearance	White powder
pH	4.0-5.0
Boiling Point	>100°C    614.2°C at 760 mmHg
Melting Point	248°C
Flash Point	325.2ºC
Density	1.01 g/mL at 25°C
Vapor Pressure	1.15E-16mmHg at 25°C
Chlorides	0.01% Max
Sulphates	0.1% Max
Iron	0.001% Max
Heavy metal	0.001% Max
Chelating value	221
NTA	0.2%
Water insoluble matter	≤0.005%
Loss on drying	8.7- 11.4%
Aminotriacetic acid	≤10 ppm
Storage	2-8°C
Chemical Risk

• Molecular Formula    C₁₀H₁₈N₂Na₂O₁₀    C₁₀H₁₄N₂O₈Na₂.₂H₂O
• Linear Formula    [-CH₂N(CH₂CO₂Na)CH₂CO₂H]₂
• Molecular Weight  336.21
• Exact Mass    336.054565
• CAS    139-33-3     6831-92-6 (Ethylenediaminetetraacetic acid disodium salt dihydrate)
• UNII    
• EC Number   205-358-3
• DSSTox Substance ID  DTXSID9027073
• IUPAC  disodium;2-[2-[carboxylatomethyl(carboxymethyl)amino]ethyl-(carboxymethyl)amino]acetate
• InChl=1S/C10H16N2O8.2Na/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);;/q;2*+1/p-2
• InChl Key      ZGTMUACCHSMWAC-UHFFFAOYSA-L
• SMILES   C(CN(CC(=O)O)CC(=O)[O-])N(CC(=O)O)CC(=O)[O-].[Na+].[Na+]
• MDL number  MFCD00070672
• PubChem Substance ID    329747771
• RTECS  AH4410000
• NCI    C65508
• FEMA     4520  
• HS Code          2922499990
• Beilstein     3822669
• eCl@ss    39030907
• NACRES NA.25

Synonyms : 

Ethylenediaminetetraacetic acid, Disodium salt, Disodic EDTA, Disodic edetate, Acid Edetic

References_____________________________________________________________________

(1) Retrievability of calcium hydroxide intracanal medicament with three calcium chelators, ethylenediaminetetraacetic acid, citric acid, and chitosan from root canals: An in vitro cone beam computed tomography volumetric analysis.
Raghu R, Pradeep G, Shetty A, Gautham PM, Puneetha PG, Reddy TVS.
J Conserv Dent. 2017 Jan-Feb;20(1):25-29. doi: 10.4103/0972-0707.209068.

Comparison of efficiency of ethylenediaminetetraacetic acid, citric acid, and etidronate in the removal of calcium hydroxide intracanal medicament using scanning electron microscopic analysis: An in-vitro study.
Chockattu SJ, Deepak BS, Goud KM.
J Conserv Dent. 2017 Jan-Feb;20(1):6-11. doi: 10.4103/0972-0707.209079.

(2) An in vitro study on the efficacy of removing calcium hydroxide from curved root canal systems in root canal therapy.
Wang Y, Guo LY, Fang HZ, Zou WL, Yang YM, Gao Y, Yang H, Hu T.
Int J Oral Sci. 2017 Jun;9(2):110-116. doi: 10.1038/ijos.2017.14. Epub 2017 Jun 23.

(3) Cosmeceutical Effects of Galactomannan Fraction from Arenga pinnata Fruits In vitro.
Yanti, Madriena, Ali S.
Pharmacognosy Res. 2017 Jan-Mar;9(1):39-45. doi: 10.4103/0974-8490.199773.

Effect of Selected Plant Phenolics on Fe2+-EDTA-H₂O₂ System Mediated Deoxyribose Oxidation: Molecular Structure-Derived Relationships of Anti- and Pro-Oxidant Actions.
de Graft-Johnson J, Nowak D.
Molecules. 2016 Dec 31;22(1). pii: E59. doi: 10.3390/molecules22010059.

(4) Determination of ethylenediaminetetraacetic acid in foods by reversed-phase high-performance liquid chromatography.
Kemmei T, Kodama S, Yamamoto A, Inoue Y, Hayakawa K.
Food Chem. 2013 Jun 1;138(2-3):866-9. doi: 10.1016/j.foodchem.2012.11.103. Epub 2012 Dec 5.

(5) Interactions between ethylenediaminetetraacetic acid (EDTA) and iron absorption pathways, in the Caco-2 model.
Kibangou IB, Bureau F, Allouche S, Arhan P, Bouglé D.
Food Chem Toxicol. 2008 Nov;46(11):3414-6. doi: 10.1016/j.fct.2008.08.014. Epub 2008 Aug 20.

(6) http://www.fao.org/ag/agn/jecfa-additives/specs/Monograph1/Additive-164.pdf

(7) Lanigan RS, Yamarik TA. Final report on the safety assessment of EDTA, calcium disodium EDTA, diammonium EDTA, dipotassium EDTA, disodium EDTA, TEA-EDTA, tetrasodium EDTA, tripotassium EDTA, trisodium EDTA, HEDTA, and trisodium HEDTA. Int J Toxicol. 2002;21 Suppl 2:95-142. doi: 10.1080/10915810290096522.