Original ArticleIron and Zinc Supplementation does not Improve Parent or Teacher Ratings of Behavior in First Grade Mexican Children Exposed to Lead
Section snippets
Participants
This randomized, double-blind trial was conducted in the city of Torreón, in the northern Mexican state of Coahuila. The main source of lead exposure was a metal foundry located close to the city center. Nine public elementary schools located within a 3.5-km radius of the foundry comprised the study site, and 724 children regularly attending first grade at the schools were eligible for enrollment (Figure). Signed parental consent was returned for 602 children. The exclusion criteria were a PbB
Sample Characteristics at Baseline
The mean (SD) blood lead concentration for the whole sample was 11.5 (6.1) μg/dL, and 51% of children had PbBs ≥ 10μg/dL.16 The overall prevalence of iron (ID; SF < 15 μg/L) and zinc deficiency (ZnD; serum zinc < 65 μg/dL) was 21.7% and 28.9%, respectively. In all other respects, the randomized groups were similar (Table I).
The mean scores at baseline for both parent and teacher ratings were well within the clinically normal range; Table II). According to parents, 17% of the children exhibited
Discussion
This study was conducted to determine whether supplementation with iron or zinc would benefit behavior ratings by parents or teachers in lead-exposed children. In this sample of children aged 6 to 8 years, 51% had PbB ≥ 10 μg/dL, and 6% were rated by both parents and teachers as exhibiting ADHD-like behaviors. Alternative treatment of ADHD and other behavior problems in children is not new, either because parents prefer not to use stimulant medication with young children or because children do
References (29)
- et al.
A twelve-year follow-up of preschool hyperactive children
J Am Acad Child Adolesc Psychiatry
(1991) - et al.
Pre- and postnatal lead exposure and behavior problems in school-aged children
Environ Res
(1994) - et al.
Early exposure to lead and juvenile delinquency
Neurotoxicol Teratol
(2001) - et al.
Relationship between blood lead and dietary iron intake in preschool children
Ann of Epidemiol
(1996) - et al.
Association between iron deficiency and blood lead level in a longitudinal analysis of children followed in an urban primary care clinic
J Pediatr
(2003) - et al.
Effects of iron therapy on infant blood lead levels
J Pediatr
(2003) - et al.
Double-blind, placebo-controlled study of zinc sulfate in the treatment of attention deficit hyperactivity disorder
Progr Nuero-Psychopharmacol Biol Psychiatry
(2004) - et al.
Blood lead, anemia, and short stature are independently associated with cognitive performance in Mexican school children
J Nutr
(2004) The evidence linking zinc deficiency with children's cognitive and motor functioning
J Nutr
(2003)- et al.
Zinc deficiency in attention-deficit hyperactivity disorder
Biol Psychiatry
(1996)
Effects of repletion of zinc and other micronutrients on neuropsychologic performance and growth of Chinese children
Am J Clin Nutr
A randomized, double-blind, placebo-controlled trial of docosohexaenoic acid supplementation in children with attention-deficit/hyperactivity disorder
J Pediatr
Lifetime low-level exposure to environmental lead and children's emotional and behavioral development at ages 11-13 years. The Port Pirie Cohort Study
Am J Epidemiol
Association between iron deficiency and low-level lead poisoning in an urban primary care clinic
Am J Public Health
Cited by (44)
Effects of environmental and occupational lead toxicity and its association with iron metabolism
2022, Toxicology and Applied PharmacologyCitation Excerpt :The occurring iron deficiency may be also associated with higher sensitivity of ferrochelatase (that is sensitive to the toxic effects of lead), thus iron supplementation is considered a good approach to prevent the toxic effect of Pb on hematopoiesis (Martínez-Hernanz et al., 2020). A majority of reviewed studies proved that introducing iron supplements to lead-exposed subjects resulted in a significant decline in blood Pb levels (Wasserman et al., 1994; Ruff et al., 1996; Wolf et al., 2003; Kordas et al., 2005; Zimmermann et al., 2006; Park et al., 2014; Bouhouch et al., 2016; Salendu et al., 2017; Tiwari et al., 2020). A longitudinal study on the role of diet and daily consumption of protein, iron, zinc, calcium, vitamin D and fat, shown an inverse association between dietary iron intake at 3–6 months of age and Pb levels of 6-month children, and between iron intake at 9–12 months of age and Pb concentrations of 12-month subjects (Schell et al., 2004).
Relationship between lead absorption and iron status and its association with oxidative stress markers in lead-exposed workers
2021, Journal of Trace Elements in Medicine and BiologyAssociation between circulating zinc/ferritin levels and parent Conner's scores in children with attention deficit hyperactivity disorder
2019, European PsychiatryCitation Excerpt :In group 2, there was statistically significant improvement in all Conner’s rating scale including oppositional, cognitive problems, hyperactivity, impulsivity, emotion liability and inattention subscales after iron and zinc supplementation for 6 months (P < 0.05). In Consistent with our findings, Kordas et al. [34] reported that there was also an iron by zinc interaction. Children with Zn deficiency receiving either placebo or the combined treatment had greater declines in mean hyperactive score than the other 2 groups (iron alone and zinc alone).
Iron and Zinc Supplementation Does Not Impact Urinary Arsenic Excretion in Mexican School Children
2017, Journal of Pediatrics
Supported by The Spencer Foundation, Chicago, Ill