Calcium disodium EDTA

Under European Directive 95/2/EC, calcium disodium EDTA is permitted only in a limited number of foods, including some canned and bottled products, with maximum levels specified in each case. In the United States (Code of Federal Regulations) it is permitted to a level of 33 ppm in canned carbonated soft drinks, to promote flavour retention. 

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Urinary lead levels have also been used to measure current exposure (Robinson 1974) but they are of questionable value as biomarkers of exposure because of the relatively low and fluctuating lead levels that are excreted in the urine (ACGIH 1986 Ibels and Pollock 1986 Jensen 1984). In contrast, the determination of urinary lead following a single injection of the chelating agent, calcium disodium EDTA, which mobilizes extracellular lead and produces increased urinary excretion of lead, is presumed to be indicative of an elevated body burden of lead (Cory-Slechta et al. 1987 Ibels and Pollock 1986 Janin et al. 1985). Children whose PbB levels are 45 pg/dL should not receive a provocative chelation... 

A common form of EDTA used as a preservative is calcium disodium EDTA (CaNa2EDTA). What metals will this form of the sequestrant scavenge effectively The dissolution of the solid will yield calcium ions, sodium ions, and the EDTA anion. Any metal more effectively complexed than calcium will be readily scavenged, including all ions listed in Table 9.1 except silver (Ag+) and magnesium (Mg2+). (In the absence of the calcium counterion, as in the case of the acid form of EDTA, chelation of calcium in the body can occur. In fact, EDTA administered orally is an FDA-approved treatment for calcium deposits in the bloodstream that lead to cardiovascular disease.) Citric acid (Fig. 9.3.3) is another sequestrant of metal ions in foodstuffs. 

In mammals, phenobarbital and phenytoin increase serum ceruloplasmin concentrations (Aaseth and Norseth 1986). Chronic copper poisoning in sheep is exacerbated when diets contain heliotrope plants (Heliotropium sp., Echium spp., Senecio sp.). Aggravated effects of the heliotrope plants include reduced survival and a twofold to threefold increase in liver and kidney copper concentrations when compared to control animals fed copper without heliotropes (Howell et al. 1991). Rats given acutely toxic doses of 2,3,7,8-tetrachlorodibenzo-para-dioxin had elevated concentrations of copper in liver and kidney because of impaired biliary excretion of copper (Elsenhans et al. 1991). Morphine increases copper concentrations in the central nervous system of rats, and dithiocarbam-ates inhibit biliary excretion (Aaseth and Norseth 1986). In human patients, urinary excretion of copper is increased after treatment with D-penicillamine, calcium disodium EDTA, or calcium trisodium diethylenetriamine penta acetic acid (Flora 1991). 

E 385 Calcium disodium ethylene diamine tetra-acetate (Calcium disodium EDTA)... 

Dimercaprol is FDA-approved as single-agent treatment of acute poisoning by arsenic and inorganic mercury and for the treatment of severe lead poisoning when used in conjunction with edetate calcium disodium (EDTA see below). Although studies of its metabolism in humans are limited, intramuscularly administered dimercaprol appears to be readily absorbed, metabolized, and excreted by the kidney within 4-8 hours. Animal models indicate that it may also undergo biliary excretion, but the role of this excretory route in humans and other details of its biotransformation are uncertain. 

Injection of calcium disodium EDTA does not affect blood calcium levels but heavy metal ions in the body have a higher affinity for EDTA than does calcium, and hence these metals readily exchange in vivo to form soluble EDT A-heavy-metal complexes that are excreted in the urine. Because of its poor absorption from the alimentary tract, calcium disodium EDTA is usually injected intramuscularly or intravenously. These considerations led to its being used, initially in 195270), to treat lead encephalopathy. 

This danger is minimal if calcium disodium EDTA is used as the chelating agent and it has now become the material of choice in cases of lead poisoning. Except in massive doses it is almost nontoxic and treatment with CaNa2EDTA results in a rapid depletion of lead in the soft tissues prolonged treatment is necessary for the removal of lead from bone72). 

Calcium Disodium EDTA occurs as white, crystalline granules or as a white to off white powder. It is slightly hygroscopic and is stable in air. It is freely soluble in water. 

Chromatographic System (See Chromatography, Appendix IIIA.) Set up the system with reference to High-Performance Liquid Chromatography. The chromatograph has a 254-nm detector and a 15-cm x 4.6-mm column that contains 5-to 10-mm porous microparticles of silica bonded to octylsilane (Zorbax 8, or equivalent). Set the flow rate to about 2 mL/ min. Chromatograph three replicate injections of the Standard Preparation, and record the peak responses as directed under Procedure. The relative standard deviation is not more than 2.0%, and the resolution factor between nitrilotriacetic acid and Calcium Disodium EDTA is not less than 4.0. 

Procedure Separately inject equal volumes (about 50 jxL) of the Standard Preparation and the Test Preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. The retention times are about 3.5 min for nitrilotriacetic acid and 9 min for Calcium Disodium EDTA. The response of the nitrilotriacetic acid peak of the Test Preparation does not exceed the difference between the nitrilotriacetic acid peak responses obtained from the Standard Preparation and the Test Preparation. 

Calcium Carbonate, 55 Calcium Chloride, 56, (Sl)5 Calcium Chloride, Anhydrous, 56 Calcium Chloride Double Salt of dl- or d-Calcium Pantothenate, 66 Calcium Chloride Solution, 57, (Sl)6 Calcium Chloride TS, 850 Calcium Citrate, 58, (S2)4 Calcium Disodium Edetate, 59 Calcium Disodium EDTA, 59 Calcium Disodium... 

Saxena, G., Flora, S.J.S. (2004). Lead induced oxidative stress and hematological alterations and their response to combined administration of calcium disodium EDTA with a thiol chelator in rats. J. Biochem. Mol. Toxicol. 18 221-33. 

Preservatives including but not limited to the following within these maximum amounts in percent by weight of the finished food Sorbic acid, benzoic acid and their sodium, potassium, and calcium salts, individually, 0.1 percent, or in combination, 0.2 percent, expressed as the acids calcium disodium EDTA, 0.0075 percent propyl, octyl, and dodecyl gallates, BHT, BHA, ascorbyl palmitate, ascorbyl stearate, all individually or in combination, 0.02 percent stearyl citrate, 0.15 percent isopropyl citrate mixture, 0.02 percent. 

In chronic intoxication, the therapeutic objective is removal of the patient from the site of exposure and elimination of the noxa from the body (e. g. detoxification measures, infusions of calcium-disodium EDTA in cases of lead poisoning, etc.). There is no justification whatsoever for therapeutic nihilism. With the aid of dietetic measures (if necessary) and adjuvant therapy (N-acetylcysteine, antioxidants, ursodeoxycholic acid, S-adenosyl-methionine, etc.), the clinical course and hence the prognosis can be favourably influenced. Insufficient regression or inadequate normalization of laboratory parameters and histological changes despite removal of the patient from the area of exposure must arouse suspicion of a further, still existing noxa (alcohol, medicaments, other chemicals). 

Calcium disodium EDTA 9 0.01-0.1% Wydase (Wyeth-Ay erst) 0.1% w/v... 

In rats, more live fetuses resulted when calcium disodium EDTA was used to treat lead poisoning. However, in rats that were not lead poisoned, increases in submucous clefts, cleft palate, syndactyly, adactyly, abnormal ribs, and abnormal vertebrae occurred. Eurthermore, the doses of EDTA in the study were comparable to those used in man and without noticeable changes in the mother. Since zinc calcium EDTA did not cause teratogenicity at low levels in rats, zinc calcium EDTA should be available for use in pregnancy. 

Lanigan RS and Yamarik TA (2002) 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 HE-DTA. International Journal of Toxicology 21 95-142. 

Leckie WJH, Tomsett SL. The diagnostic and therapeutic use of edathamil calcium disodium (EDTA Versene) in excessive inorganic lead absorption. Q J Med 1958 27 65-82. 

Ibim SE, Trotman J, Musey PI, et al. 1992. Depletion of essential elements by calcium disodium EDTA treatment in the dog. Toxicology 73 229-237. 

EDTA, CALCIUM (CALCIUM DISODIUM EDTA, CALCIUM DISODIUM EDETATE, CALCIUM DISODIUM VERSENATE)... 

Section II Arsenic Arsine Lead Mercury Section III BAL (Dimercaprol) EDTA, Calcium (Calcium Disodium EDTA, Calcium Disodium Edetate, Calcium Disodium Versenate) Succimer (DMSA) Unithiol (DMPS)... 

Synonyms CAS 813-94-5 lime citrate tricalcium citrate Calcium Disodium Edta... 

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