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Association of Salt Iodization and Urine Iodine Concentration in Schoolchildren from Public Schools in Northeast of Brazil

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Abstract

Iodine deficiency (ID) is recognized as a leading risk factor for child development. Universal salt iodization (USI) is an effective and well-established intervention strategy for the prevention of iodine deficiency disorders (IDD). To evaluate the levels of iodine in household salt samples and the urinary iodine concentration (UIC) in schoolchildren aged 6 to 14 years in public schools in Bahia, Brazil. A cross-sectional study was conducted with 1231 students (6 to 14 years old) from 17 public schools in Bahia. The iodine concentration was evaluated in salt and UIC samples. The adapted Sandell–Kolthoff reaction was used to determine urinary iodine levels. A spectrophotometer (UV-Vis) was used to examine the reduction of ceric ammonium sulfate. A standard iodine solution using a potassium iodate was used to extrapolate the iodine concentrations. The total of 665 salt samples had a median iodine concentration of 24 mg/kg (25th–75th percentile 17.0 to 28.5 mg/kg). The largest proportion (79.6%) of salt samples had iodine concentration in the recommended range, 17.6% of the samples presented iodine at a salt concentration below the established level (<15 mg/kg) and a small proportion was above it (2.8%). The general mean urinary iodine concentration (MUIC) was 217.53 ± 28.30 μg/L and median was 205.50 μg/L. The students evaluated and the salt samples analyzed showed satisfactory results, as recommended by Brazilian legislation and nutritional recommendations of the World Health Organization (WHO).

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Data Availability

The data that support the findings of this study are available from the corresponding author, [HER], upon reasonable request.

Abbreviations

UIC:

Urinary iodine concentration

USC:

Urinary selenium concentration

TH:

Thyroid hormones

WHO:

World Health Organization

IoD:

Iodine deficiency

IDD:

Iodine deficiency disorder

EII:

Excessive iodine intake

TSH:

Thyroid-stimulating hormone

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Funding

Fapesb (Fundação de Apoio à Pesquisa no Estado da Bahia).

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Authors and Affiliations

  1. Health and Science Center, Federal University of Bahia Reconcavo, BA, Santo Antonio de Jesus, Brazil

    Renata de Oliveira Campos

  2. Postgraduate Program in Interactive Processes of Organs and Systems, Health & Science Institute, Federal University of Bahia, Salvador, BA, Brazil

    Renata de Oliveira Campos & Helton Estrela Ramos

  3. Bioregulation Department, Health and Science Institute, Federal University of Bahia, Avenida Reitor Miguel Calmon, S/N. Vale do Canela. Room 301, Salvador, BA, Brazil

    Renata de Oliveira Campos, Sara Cristina Rebouças Lima, Jair de Souza Braga Filho, Joice Santos de Jesus, Sara Moreira Anunciação, Gabriela Flor Martins, Lorena Maia de Jesus, Aline dos Anjos Santana & Helton Estrela Ramos

  4. Health & Science Center, Federal University Recôncavo da Bahia, Santo Antonio de Jesus, Bahia, Brazil

    Sara Moreira Anunciação

  5. Department of Veterinary Medicine, Faculty of Animal Science and Food Engineering of University of São Paulo, Pirassununga, São Paulo, Brazil

    Vanessa Cristina de Oliveira Souza

  6. Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto of University of São Paulo, Ribeirão Preto, São Paulo, Brazil

    Fernando Barbosa Júnior

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  1. Renata de Oliveira Campos
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Corresponding author

Correspondence to Helton Estrela Ramos.

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The authors declare that they have no conflict of interest.

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The study was approved by the Committee on Ethics in Research of the Federal University of Bahia. CAAE: 11859113.8.0000.5531.

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All participants voluntarily participated in the study, and written consent was obtained from at least one parent or guardian.

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de Oliveira Campos, R., Lima, S.C.R., de Souza Braga Filho, J. et al. Association of Salt Iodization and Urine Iodine Concentration in Schoolchildren from Public Schools in Northeast of Brazil. Biol Trace Elem Res 199, 4423–4429 (2021). https://doi.org/10.1007/s12011-020-02571-4

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