EDTA, also known as disodium EDTA, EDTA disodium or ethylenediamine tetraacetic acid, is a widely used chemical compound found in personal care, skin care, processed foods, cosmetic preparations and cleaning products. EDTA has extensive medical, engineering, agricultural and industrial applications as well. With its wide range of uses and frequent presence in our everyday lives, it is important to know about the purpose of EDTA, how it is used and if there are any dangers involved in its use.
- Industrial cleaning: complexation of Ca2+ and Mg2+ ions, binding of heavy metals.
- Detergents: complexation of Ca2+ and Mg2+ (reduction of water hardness).
- Photography: use of Fe(III)EDTA as oxidizing agent.
- Pulp and paper industry: complexation of heavy metals during chlorine-free bleaching, stabilization of hydrogen peroxide.
- Textile industry: complexation of heavy metals, bleach stabilizer.
- Hydroponics: iron-EDTA is used to make iron more soluble in nutrient solutions.
More specialised uses of EDTA are:
- Food: added as preservative to prevent catalytic oxidation by metal ions or stabilizer and for iron fortification.
- Approved by the FDA as a preservative in packaged foods, vitamins, and baby food.
- Personal care: added to cosmetics to improve product stability.
- Oil production: added into the borehole to inhibit mineral precipitation.
- Dairy and beverage industry: cleaning milk stains from bottles.
- Flue gas cleaning: removal of NOx.
- Dentistry as a root canal irrigant to remove organic and inorganic debris.
- Soft drinks containing ascorbic acid and sodium benzoate, to lessen the formation of benzene (a carcinogen).
- Recycling: rejuvenate old lead acid batteries.
- EDTA is used in chelation therapy for acute hypocalcaemia, mercury poisoning and lead poisoning.
- Combined with chromium, EDTA is used to evaluate kidney function. It is administered intravenously and its filtration into the urine is monitored. This method is considered the gold standard for evaluating glomerular filtration rate, Cr-EDTA’s sole way out of the body is via glomerular filtration as it is not secreted or metabolised in any other way.
- Used as anticoagulant for blood samples
- In veterinary ophthalmology EDTA may be used as an anticollagenase to prevent the worsening of corneal ulcers in animals.
In laboratory science, EDTA is also used for:
- Scavenging metal ions: in biochemistry and molecular biology, ion depletion is commonly used to inactivate metal-dependent enzymes which could damage DNA or proteins
- Complexometric titrations.
- Buffer solutions.
- Determination of water hardness.
- EDTA may be used as a masking agent to remove a metal ion which would interfere with the analysis of a second metal ion present
- An anticoagulant in medical and laboratory equipment.
- A preservative (usually to enhance the action of another preservative such as benzalkonium or thiomersal) in ocular preparations and eye drops.
- A titrant used to determine nickel concentration in an electroless nickel plating bath.
- In metallography to remove staining due to etchants. Metal oxides are removed by gently swabbing with EDTA and rinsing in water.
Created by Mistral Pure Chemicals. View website