ABSTRACT
Objectives To explore the efficacy of CaNa2EDTA in the treatment of chronic moderate lead poisoning, so as to optimize the chelation therapy for lead poisoning in children. Methods The clinical data of 14 patients with chronic moderate lead poisoning treated with CaNa2EDTA for 3 consecutive courses of lead removal during September 2014 to December 2016 were analyzed retrospectively. Twenty-four hour urinary lead levels during hospitalization were analyzed. The changes of blood lead levels before treatment, 3 days, and 5 days after treatment were also analyzed. Results In the 14 children (4 males and 10 females) average age was 2.35±1.47 years. After treatment with CaNa2EDTA for 3 consecutive courses, the blood lead levels were decreased significantly in all the patients, and the blood lead levels at 3 days after treatment were 0.76, 0.77, 0.72 times those at 5 days after treatment respectively. The decrease of blood lead levels per unit of drug in the first 3 days of treatment were significantly higher than those in 5 days of treatment (P<0.05). The decrease of blood lead levels at 3 days after treatment was 0.65, 0.71, 0.70 times , those in 5 days' treatment respectively. The decrease of urine lead levels per unit of drug in the first 3 days of treatment were significantly higher than those in 5 days of treatment (P<0.05). Conclusions CaNa2EDTA has an obvious effect on removal of lead.The efficiency of lead removal in 3 days of treatment was higher than in 5 days of treatment. Thus, a course of treatment for 3 days may be an altenative for a course of 5 days.
ABSTRACT
Calcium disodium ethylenediaminetetraacetate (Calcium Disodium EDTA, C10H12CaN2Na2O8.2H2O) is a derivative of EthylenediamineTetraacetic Acid and is an approved food additive (E385). It is used as preservative, sequestrant, flavouring agent, and colour retention agent in foods. As a drug it is used for the reduction of blood and mobile depot lead in the treatment of acute and chronic lead poisoning. Calcium Disodium EDTA is very poorly absorbed from the gastrointestinal tract following ingestion. The compound is metabolically inert and no accumulation in the body has been found. Acute, short-term, sub chronic and chronic toxicity studies carried out with Calcium Disodium EDTA in laboratory animals found that the compound is nephrotoxic at high doses. In similar high doses, application of Calcium Disodium EDTAcan result in complexation of zinc ions, thus interfering with the zinc homeostasis and causing developmental toxicity. No evidence exists suggesting the compound exerts genotoxic or carcinogenic effects. Overall, Calcium Disodium EDTAseems to be safe for use as a food additive, as the noted toxic doses are higher than can be achieved via the addition of Calcium Disodium EDTA to food. However, human data is limited and the gross of available (human and animal) data, as well as the ADI, stems from several decades ago. Caution should also be taken when Calcium Disodium EDTA is administered as treatment for lead poisoning, as the exposure increases greatly. Until 2020, EFSA will carry out new risk assessments, and subsequently the Commission will revise the list of food additives and the conditions of use specified therein. The deadline for food additives other than colours and sweeteners is 31 December 2018, which seems appropriate regarding the non-acute need for reevaluation of Calcium Disodium EDTA as food additive.