Blood cadmium is elevated in iron deficient U.S. children: a cross-sectional study.

Monica K Silver,Betsy Lozoff,John D Meeker

doi:10.1186/1476-069x-12-117

Monica K Silver, Betsy Lozoff + Show 1 more

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https://doi.org/10.1186/1476-069x-12-117

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Abstract

BackgroundCadmium (Cd), a widespread environmental contaminant, and iron deficiency (ID), the most common nutrient deficiency in the world, are known risk factors for neurodevelopmental delays, as well as other disorders, in infants and children. Studies assessing the cumulative effects of these factors are lacking in children, despite concerns of increased uptake of metals in the presence of ID. Here we sought to determine if blood and urine Cd levels were elevated in ID children compared to non-ID children.MethodsData for 5224 children, aged 3–19 years, were obtained from the 1999–2002 NHANES. ID was defined as ≥2 of 3 abnormal iron indicators (low serum ferritin [SF], high free erythrocyte protoporphyrin [FEP], low % transferrin saturation [TSAT]); ID anemia (IDA) was defined as ID plus low hemoglobin (Hgb). Logistic regression was used to evaluate associations between ID, IDA, and abnormal iron indicators and categories of blood and urine Cd.ResultsAdjusted odds of ID, IDA, low SF, and low TSAT were associated with increasing category of blood Cd but not urine Cd. Adjusted ORs (95% CI) for blood Cd ≥0.5 μg/L versus < LOD were = 1.74 (1.30-2.34), 4.02 (1.92-8.41), 4.08 (2.36-5.89) and 1.78 (1.32-2.39), for ID, IDA, low SF, and low TSAT, respectively. Age and sex specific analyses of blood Cd and ID/abnormal iron indicators revealed that the observed associations were strongest in females aged 16–19 years.ConclusionsGiven their shared neurotoxic effects in children, and that many people live in areas with high burdens of both ID and Cd, more research into the complex relationships between nutrient deficiencies and environmental toxicants is vital.

Highlights

Cadmium (Cd), a widespread environmental contaminant, and iron deficiency (ID), the most common nutrient deficiency in the world, are known risk factors for neurodevelopmental delays, as well as other disorders, in infants and children
The prevalence of ID was 7.0% (n = 365); ID anemia (IDA) was observed in 1.5% (n = 77). 29.2% of children (n = 1603) had at least one abnormal iron indicator: 8.1% (n = 422) had low serum ferritin (SF), 10.8% (n = 563) had high Free erythrocyte protoporphyrin (FEP), 17.6% (n = 920) had low transferrin saturation (TSAT), and 5.2% (n = 269) had low Hgb
Odds of ID, IDA, low SF, and low TSAT were associated with increasing category of blood Cd

Summary

Introduction

Cadmium (Cd), a widespread environmental contaminant, and iron deficiency (ID), the most common nutrient deficiency in the world, are known risk factors for neurodevelopmental delays, as well as other disorders, in infants and children. Cadmium (Cd) is a toxic heavy metal that naturally exists in the earth’s crust. It has non-corrosive properties that make it desirable for use in a number of industrial products and processes, such as batteries, metal coatings, pigments, and plastics [1]. ID is associated with a multitude of health problems in children and adults [16]. In infants and young children, ID has been associated with poorer physical and mental development, and reduced cognitive function [1,13,17,18,19,20]

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