Children with Moderately Elevated Lead Levels: Is Chelation with DMSA Helpful?

Abstract

This study evaluates the effectiveness (use under routine circumstances) of DMSA (2,3 dimercaptosuccinic acid) and environmental remediation as compared with placebo and environmental remediation on children with blood lead (BPb) levels of 30-45 pg/dL (1.45-2.17 pmol/L). The endpoints were BPb at 1 month and 6 months after study entry. This double-blind placebo-controlled trial involved 39 children aged 2-5 years, who were randomized to one course of DMSA or placebo. The mean BPb levels of the two groups at study entry were similar, placebo group 33.0 pg/dL (1.59 pmol/L) and the DMSA group 34.9 pg/dL (1.68 pmol/L). At 1 month (the end of treatment) the mean BPb levels of the two groups were: placebo group 33.2 pg/dL (1.60 pmol/L) and the DMSA group 27.4 pg/dL (1.32 pmol/L), p=0.16. At 6 months, the mean BPb levels were 25.1 pg/dL (1.21 pmol/L) for the placebo group and 28.8 pg/dL (1.39 pmol/L) for the DMSA-treated group, p=0.06. Neither of these differences is statistically significant. All children with BPb, in the range studied here, should receive environmental evaluation and remediation; DMSA does not improve long-term blood lead levels.

Get full access to this article

View all access options for this article.

References

1. Baghurst PA , McMichael AJ , Wigg NR , et al. Environmental exposure to lead and children's intelligence at the age of seven years. The Port Pirie Cohort Study. N Engl J Med. 1992;327:1279-1284.

2. Needleman HL , Schell A , Bellinger D , et al. The long-term effects of exposure to low doses of lead in childhood: an 11-year follow-up report. N Engl J Med. 1990;322:83-88.

3. Needleman HL , Gatsonis CA . Low-level lead exposure and the IQ of children; a meta-analysis of modern studies. JAMA. 1990;263:673-678.

4. Pirkle JL , Brody DJ , Gunter EW , et al. The decline in blood lead levels in the United States: the National Health and Nutrition Examinations Surveys (NHANES). JAMA. 1994;272:284-291.

5. MMWR 1997;Feb 21:142-145.

6. Graziano JH , Lolacono NJ , Moutlon T , et al. Controlled study of meso-2,3-dimercaptosuccinic acid for the management of childhood lead intoxication.J Pediatr. 1992;120:133-139.

7. Graziano JH , Lolacono NJ , Meyer P . Dose-response study of oral 2,3-dimercaptosuccinic acid in children with elevated blood lead concentrations.J Pediatr. 1988;113:751-757.

8. Liebelt EL , Shannon M , Graef JW . Efficacy of oral meso-2,3-dimercaptosuccinic acid therapy for low-level childhood plumbism. J Pediatr. 1994;124:313-317.

9. Besunder JB , Anderson RL , Super DM . Short-term efficacy of oral dimercaptosuccinic acid in children with low to moderate lead intoxication. Pediatrics. 1995;96:683-687.

10.

10. Markowitz ME , Bijur PE , Ruff H , Rosen JF . Effects of calcium disodium versenate (CaNa2EDTA) chelation in moderate childhood lead poisoning. Pediatrics. 1993;92:265-271.

11.

11. Committee on Drugs , American Academy of Pediatrics . Treatment guidelines for lead exposure in children. Pediatrics. 1995;96:155-160.

12.

12. Charney E , Kessler B , Farfel M , Jackson D . Childhood lead poisoning: a controlled trial of the effect of dustcontrol measures on blood lead levels. N Engl J Med. 1983;309:1089-1093.

13.

13. O'Hara D . Social factors in the recurrence of increased lead absorption in children. In: Chilsolm JJ , O'Hara DM , eds. Lead Absorption in Children. Baltimore: Urban and Schwarzenberg; 1982:89-101.

14.

14. Staes C , Matte T , Copley CG , et al. Retrospective study of the impact of lead-based paint hazard remediation on children's blood lead levels in St. Louis, Missouri. Am JEpidemiol. 1994;139:1016-1026.

15.

15. Last J . Medical Dictionary of Epidemiol- ogy, 3rd ed. New York: Oxford University Press; 1995:52-52.