Title

Effects of Iron and/or Zinc Supplementation in Mexican School Children Exposed to Lead
Effects of Iron and Zinc Supplementation on Neuropsychological and Educational Achievement in Lead-exposed School Children
  • Phase

    N/A
  • Study Type

    Interventional
  • Status

    Completed No Results Posted
  • Study Participants

    602
Lead is negatively linked to nutritional status, behavior and cognition in children. Despite extensive knowledge of its toxicity and efforts to reduce exposure, lead continues to be a problem in developed and developing countries. When lead exposure is unavoidable due to its pervasive nature, effective means of protecting or disrupting that exposure need to be developed. Nutritional interventions are one such option. We conducted a 2x2 factorial, placebo-controlled trial of 6-month iron and zinc supplementation among lead-exposed children in Torreón, Mexico (altitude 1060 m). Nine schools were selected based on proximity to a lead smelter and first-graders were individually randomized to daily treatment with 30 mg iron, 30 mg zinc, both, or placebo. In addition to biochemical indicators, cognitive functions and behavior were evaluated at baseline, after the 6-month supplementation period, and again after another 6 months (without supplementation).

At baseline, 602 children ages 6.2-8.5 years were enrolled.
We conducted a 2x2 factorial, placebo-controlled trial of 6-month iron and zinc supplementation among lead-exposed children in Torreón, Mexico (altitude 1060 m) to test the hypothesis that supplementation with iron, zinc or both will reduce blood lead concentrations of the children and improve their cognition and behavior. Nine schools were selected based on proximity to a lead smelter and first-graders were individually randomized to daily treatment with 30 mg iron, 30 mg zinc, both, or placebo. In addition to biochemical indicators (blood lead, serum ferritin, CRP, serum zinc, urinary arsenic concentrations), cognitive functions and behavior were measured. Assessments were conducted at three time points: at baseline, after the 6 month treatment, and again after another 6 months without treatment. At baseline, 602 children ages 6.2-8.5 years were enrolled.
Study Started
Jan 31
2000
Primary Completion
Dec 31
2001
Study Completion
Dec 31
2001
Last Update
Jan 26
2015
Estimate

Dietary Supplement Ferrous fumarate

Tablet formulated from 30 mg ferrous fumarate.

Dietary Supplement Zinc oxide

Tablet formulated from 30 mg zinc oxide

Dietary Supplement Placebo

Ferrous fumarate Experimental

Tablet formulated as ferrous fumarate, 30 mg. Given once daily for 6 months.

Zinc oxide Experimental

Tablet formulated as zinc oxide, 30 mg. Given once daily by mouth for 6 months.

Ferrous fumarate and zinc oxide Experimental

Tablet, formulated as ferrous fumarate 30 mg plus zinc oxide 30 mg. Given once daily by mouth for 6 months.

Placebo Placebo Comparator

Sugar tablet formulated to look like the experimental arms of the study. Given daily by mouth for 6 months.

Criteria

Inclusion Criteria:

1st grade child

Exclusion Criteria:

Blood lead concentration =>45 ug/dL
Hemoglobin concentration < 9 g/dL
No Results Posted