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Liu S, Sharp A, Luo X, Lane S, Villanueva EV, Lu Z, Ma ZF. The use of breast milk iodine concentration in the first week of lactation as a biomarker of iodine status in breast-feeding women. Br J Nutr 2024; 131:286-295. [PMID: 37642155 DOI: 10.1017/s0007114523001897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Breast milk iodine concentration (BMIC) is a promising indicator of iodine status in lactating women. However, there are limited data on its usefulness to reflect maternal iodine deficiency. Therefore, the aim of our study was to assess iodine concentration in breast milk and urine samples in exclusively breast-feeding women. Eligible pregnant women undergoing routine antenatal care in a large hospital in Shaanxi Province, China, were followed up from the third trimester of pregnancy until the first week of lactation. Urine samples (20 ml) were collected during pregnancy and lactation. Iodine concentration in samples was measured based on Sandell-Kolthoff reaction. Breast milk samples (5 ml) were provided during lactation. A receiver operating curve (ROC) was constructed to determine the diagnostic performance of BMIC. An iodine-specific FFQ was completed twice during pregnancy and lactation. A total of 200 women completed the study. The overall median BMIC was 89 μg/l, indicating iodine sufficiency (i.e. BMIC reference range between 60 and 465 μg/l). Women reported similar median urinary iodine concentration (UIC) during pregnancy and lactation (112 and 113 μg/l, respectively), but their iodine status differed - mild-to-moderate iodine deficiency during pregnancy and iodine sufficiency during lactation. The ROC for BMIC using UIC as a reference standard was 0·755 (95 % CI: 0·644, 0·866). In conclusion, this study demonstrated that women were iodine sufficient in the first week of lactation as assessed by UIC, which was consistent with BMIC. These findings suggested that BMIC is a useful biomarker to assess iodine status in lactating women.
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Affiliation(s)
- Shuchang Liu
- Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou215123, People's Republic of China
- Harris-Wellbeing Research Centre, Faculty of Health & Life Sciences, University of Liverpool, LiverpoolL8 7SS, UK
| | - Andrew Sharp
- Harris-Wellbeing Research Centre, Faculty of Health & Life Sciences, University of Liverpool, LiverpoolL8 7SS, UK
| | - Xiaoqin Luo
- School of Public Health, Xi'an Jiaotong University, Xi'an710006, People's Republic of China
| | - Steven Lane
- Health Data Science, University of Liverpool, Liverpool, UK
| | - Elmer V Villanueva
- School of Science, Xi'an Jiaotong-Liverpool University, Suzhou215123, People's Republic of China
- Victoria University, Footscray Victoria Melbourne3011, Australia
| | - Zhiliang Lu
- Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou215123, People's Republic of China
| | - Zheng Feei Ma
- School of Science, Xi'an Jiaotong-Liverpool University, Suzhou215123, People's Republic of China
- Centre for Public Health and Wellbeing, School of Health and Social Wellbeing, College of Health, University of the West of England, BristolBS16 1QY, UK
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Pang J, Huang Y, Liu Y, Huang W. Applications of ion chromatography in urine analysis: A review. J Chromatogr A 2023; 1706:464231. [PMID: 37517316 DOI: 10.1016/j.chroma.2023.464231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 07/17/2023] [Accepted: 07/19/2023] [Indexed: 08/01/2023]
Abstract
Ion chromatography (IC) plays a crucial role in urine analysis for diverse medical diagnoses. This paper reviews a comprehensive investigation into urine pretreatment techniques, as well as the design and development of IC systems for the measurement of various chemicals. Prior to analysis, urine samples commonly undergo pretreatment procedures such as dilution, filtration, purification, and concentration. These steps effectively eliminate interfering factors and facilitate the accurate and sensitive analysis of ultra-trace components. To separate and quantify different chemical elements or ions present in urine, a range of homemade or commercially available columns coupled with various detectors were employed. This study focuses on the analysis of chemicals such as heavy metals, halogens, pesticides, drugs, and other essential or toxic substances by IC methods.
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Affiliation(s)
- Jiafeng Pang
- Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan 430078, Hubei, China
| | - Yongming Huang
- Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan 430078, Hubei, China
| | - Yanli Liu
- Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan 430078, Hubei, China
| | - Weixiong Huang
- Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan 430078, Hubei, China.
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Variations in Breast Milk Iodine Concentration over 24 h among Lactating Women in Northern China. J Nutr 2023; 153:208-214. [PMID: 36913455 DOI: 10.1016/j.tjnut.2022.11.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 11/10/2022] [Accepted: 11/28/2022] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Adequate breast milk iodine concentration (BMIC) is essential for the growth and cognitive development of exclusively breastfed infants; however, data on variations in BMIC over 24 h are limited. OBJECTIVE We aimed to explore in lactating women the variation in 24-h BMIC. METHODS Thirty pairs of mothers and breastfed infants aged 0-6 mo were recruited from the cities of Tianjin and Luoyang, China. A 3-d 24-h dietary record, including salt intake, was performed to assess the dietary iodine intake of lactating women. Breast milk samples before and after each feeding for 24 h and 24-h urine samples were collected from the women for 3 d to estimate iodine excretion. A multivariate linear regression model was used to analyze the factors influencing BMIC. A total of 2658 breast milk samples and 90 24-h urine samples were collected. RESULTS The median BMIC and 24-h urine iodine concentration (UIC) of lactating women for a mean of 3.6 ± 1.48 mo were 158 μg/L and 137 μg/L, respectively. The interindividual variability of BMIC (35.1%) was higher than that observed within individuals (11.8%). The variation in BMIC showed a "V" shaped curve over 24 h. The median BMIC at 08:00-12:00 (137 μg/L) was significantly lower than that at 20:00-24:00 (163 μg/L) and 00:00-04:00 (164 μg/L). A progressively increasing curve was obtained for BMIC until it peaked at 20:00 and plateaued at a higher concentration from 20:00 to 04:00 than at 08:00-12:00 (all P < 0.05). BMIC was associated with dietary iodine intake (β: 0.366; 95% CI: 0.004, 0.018) and infant age (β: -0.432; 95% CI: -1.07, -0.322). CONCLUSIONS Our study shows that the BMIC presents a "V" shaped curve over 24 h. We recommend that breast milk samples be collected between 08:00 and 12:00 for evaluation of the iodine status of lactating women.
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Guo W, Wu W, Gao M, Yang Y, Pearce EN, Li S, Ren Z, Zhang N, Zhang K, Pan Z, Zhang W. Characteristics and predictors of breast milk iodine in exclusively breastfed infants: Results from a repeated-measures study of iodine metabolism. Front Nutr 2022; 9:1017744. [PMID: 36438740 PMCID: PMC9682142 DOI: 10.3389/fnut.2022.1017744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 10/19/2022] [Indexed: 11/10/2022] Open
Abstract
Background The iodine supply of exclusively breastfed infants entirely depends upon breast milk. Changes in breast milk iodine affect infants’ iodine nutritional status. This study aimed to comprehensively assess the characteristics and predictors of breast milk iodine concentration (BMIC). Materials and methods This 7-day iodine metabolism experiment was conducted in 25 exclusively breastfed mother-infant pairs. The duplicate portion method was used to measure the mother’s daily iodine intake from foods and water, and maternal 24-h urine excretion was assessed. We recorded the number of breastfeeds per mother per day and collected breast milk samples before and after each feeding. Results The median [quartile (Q)1–Q3 range] of BMIC was 115 (86.7, 172) μg/L. The BMIC before breastfeeding was generally higher than that after breastfeeding. Time-sequential analysis found that morning BMIC was most highly correlated with the prior day’s iodine intake. Breast milk samples taken in the afternoon or after midnight are closer to the median level of BMIC throughout the day. The number of breast milk samples needed to estimate the iodine level with 95% CI within precision ranges of ± 20% was 83 for a population, 9 for an individual, and 2 for an individual’s single day. Maternal total iodine intake (TII) and urine iodine were significantly associated with BMIC. 24-h urinary iodine excretion (24-h UIE) was found to be the best predictive indicator for the BMIC (β = 0.71, 95% CI: 0.64, 0.79). Conclusion BMIC is a constantly changing indicator and trended downward during each breastfeeding. Breast milk samples taken in the afternoon or after midnight are most representative. BMIC was significantly associated with recent iodine intake. Maternal 24-h UIE was the best predictor of BMIC.
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Affiliation(s)
- Wenxing Guo
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Wen Wu
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Min Gao
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Ying Yang
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Elizabeth N. Pearce
- Section of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, Boston, MA, United States
| | - Shaohan Li
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Zhiyuan Ren
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Naifan Zhang
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Kexin Zhang
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Ziyun Pan
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Wanqi Zhang
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
- The Key Laboratory of Hormone and Development (Ministry of Health), Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
- *Correspondence: Wanqi Zhang,
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Andersson M, Braegger CP. The Role of Iodine for Thyroid Function in Lactating Women and Infants. Endocr Rev 2022; 43:469-506. [PMID: 35552681 PMCID: PMC9113141 DOI: 10.1210/endrev/bnab029] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Indexed: 12/18/2022]
Abstract
Iodine is a micronutrient needed for the production of thyroid hormones, which regulate metabolism, growth, and development. Iodine deficiency or excess may alter the thyroid hormone synthesis. The potential effects on infant development depend on the degree, timing, and duration of exposure. The iodine requirement is particularly high during infancy because of elevated thyroid hormone turnover. Breastfed infants rely on iodine provided by human milk, but the iodine concentration in breast milk is determined by the maternal iodine intake. Diets in many countries cannot provide sufficient iodine, and deficiency is prevented by iodine fortification of salt. However, the coverage of iodized salt varies between countries. Epidemiological data suggest large differences in the iodine intake in lactating women, infants, and toddlers worldwide, ranging from deficient to excessive intake. In this review, we provide an overview of the current knowledge and recent advances in the understanding of iodine nutrition and its association with thyroid function in lactating women, infants, and toddlers. We discuss risk factors for iodine malnutrition and the impact of targeted intervention strategies on these vulnerable population groups. We highlight the importance of appropriate definitions of optimal iodine nutrition and the need for more data assessing the risk of mild iodine deficiency for thyroid disorders during the first 2 years in life.
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Affiliation(s)
- Maria Andersson
- Nutrition Research Unit, University Children's Hospital Zurich, CH-8032 Zürich, Switzerland
| | - Christian P Braegger
- Nutrition Research Unit, University Children's Hospital Zurich, CH-8032 Zürich, Switzerland
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Breast Milk Iodine Concentration (BMIC) as a Biomarker of Iodine Status in Lactating Women and Children <2 Years of Age: A Systematic Review. Nutrients 2022; 14:nu14091691. [PMID: 35565659 PMCID: PMC9104537 DOI: 10.3390/nu14091691] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/28/2022] [Accepted: 04/01/2022] [Indexed: 01/01/2023] Open
Abstract
Background: Iodine is needed for the production of thyroid hormones, which are essential for infant growth and development. Given that there are wide variations in breast milk iodine concentration (BMIC) and urinary iodine concentration (UIC), it is unclear if BMIC is associated with UIC in populations residing in iodine sufficient or deficient areas. Aim: To investigate if BMIC can be used as a biomarker for iodine status in lactating women and children <2 years of age. Methods: Electronic databases; PubMed, Web of Science and Scopus were searched until year 2021, for studies investigating the relationship between BMIC and UIC. Studies were reviewed for eligibility, according to inclusion and exclusion criteria, followed by data extraction, according to the PRISMA guidelines. Results: Overall, 51 studies met the criteria for inclusion in the systematic review. BMIC ranged from 18 to 1153 µg/L. In iodine-deficient and iodine-sufficient lactating women, BMIC ranged from 26 to 185 µg/L and 15 to 1006 µg/L, respectively. In most studies, the categorisation of iodine status assessed by median UIC was consistent with the categorisation of iodine status assessed by median BMIC cut off of ≥100 µg/L, to determine iodine sufficiency in lactating women and children <2 years of age. Conclusions: The systematic review indicated that BMIC is a promising biomarker of iodine status in lactating women and children <2 years of age. However, these data need to be interpreted cautiously, given the study limitations in the included studies. Future studies should consider investigating the optimal median BMIC, as there is a lack of high-quality observational and intervention studies in lactating women and infants.
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Siro SS, Baumgartner J, Schoonen M, Ngounda J, Malan L, Symington EA, Smuts CM, Zandberg L. Characterization of Genetic Variants in the SLC5A5 Gene and Associations With Breast Milk Iodine Concentration in Lactating Women of African Descent: The NUPED Study. Front Nutr 2021; 8:692504. [PMID: 34368208 PMCID: PMC8342754 DOI: 10.3389/fnut.2021.692504] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 06/22/2021] [Indexed: 11/13/2022] Open
Abstract
Background: The sodium iodide symporter is responsible for the transfer of iodine into breast milk and is encoded for by the SLC5A5 gene. The role of genetic variants in the SLC5A5 gene locus in relation to the transfer of iodine from plasma into breast milk in healthy lactating individuals has, to our knowledge, not been explored. Objective: To identify and characterize possible genetic variants of the SLC5A5 gene in women of African descent living in urban South Africa, and to study associations with breast milk iodine concentrations (BMIC) in lactating women. Methods: This study is affiliated to the Nutrition during Pregnancy and Early Development (NuPED) cohort study (n = 250 enrolled pregnant women). In a randomly selected sub-sample of 32 women, the SLC5A5 gene was sequenced to identify known and novel variants. Of the identified variants, genotyping of selected variants was performed in all pregnant women who gave consent for genetic analyses (n = 246), to determine the frequency of the variants in the study sample. Urinary iodine concentration (UIC) in spot urine samples and BMIC were measured to determine iodine status. Associations of SLC5A5 genetic variants with BMIC were studied in lactating women (n = 55). Results: We identified 27 variants from sequencing of gene exomes and 10 variants were selected for further study. There was a significant difference in BMIC between the genotypes of the rs775249401 variant (P = 0.042), with the homozygous GG group having lower BMIC [86.8 (54.9-167.9) μg/L] compared to the (A) allele carriers rs775249401(AG+AA) [143.9 (122.4-169.3) μg/L] (P = 0.042). Of the rs775249401(GG), 49% had UIC <100 μg/L and 61% had BMIC <100 μg/L. On the other hand, 60% of the rs775249401(AG+AA) carriers had UIC <100 μg/L, and none had a BMIC <100 μg/L. Conclusion: Our results suggest that A-allele carriers of rs775249401(AG+AA) are likely to have higher iodine transfer into breast milk compared to the homozygous GG counterparts. Thus, genetic variations in the SLC5A5 gene may play an important role in the transfer of iodine from plasma into breast milk and may partially explain inter-individual variability in BMIC.
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Affiliation(s)
- Sicelosethu S. Siro
- Centre of Excellence for Nutrition, North-West University, Potchefstroom, South Africa
| | - Jeannine Baumgartner
- Centre of Excellence for Nutrition, North-West University, Potchefstroom, South Africa
- Human Nutrition Laboratory, Department of Health Sciences and Technology, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Maryke Schoonen
- Centre of Excellence for Nutrition, North-West University, Potchefstroom, South Africa
| | - Jennifer Ngounda
- Department of Nutrition and Dietetics, University of the Free State, Bloemfontein, South Africa
| | - Linda Malan
- Centre of Excellence for Nutrition, North-West University, Potchefstroom, South Africa
| | - Elizabeth A. Symington
- Department of Life and Consumer Sciences, University of South Africa, Johannesburg, South Africa
| | - Cornelius M. Smuts
- Centre of Excellence for Nutrition, North-West University, Potchefstroom, South Africa
| | - Lizelle Zandberg
- Centre of Excellence for Nutrition, North-West University, Potchefstroom, South Africa
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Manousou S, Augustin H, Eggertsen R, Hulthén L, Filipsson Nyström H. Inadequate iodine intake in lactating women in Sweden: A pilot 1-year, prospective, observational study. Acta Obstet Gynecol Scand 2021; 100:48-57. [PMID: 32880886 PMCID: PMC7756844 DOI: 10.1111/aogs.13986] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/12/2020] [Accepted: 08/25/2020] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Breastfed infants depend on breast-milk iodine for growth and brain development, as iodine is a trace element important for thyroid hormone production. Iodine need is higher during lactation; hence, mothers and children are at risk of iodine deficiency. We aimed to explore maternal iodine and thyroidal status during lactation. MATERIAL AND METHODS Pregnant women were recruited in Gothenburg, southwest Sweden. Maternal urine and serum were collected at pregnancy week 35-37 (n = 84) and 0.5, 4, and 12 months postpartum. Seventy mothers provided breast milk at 0.5 months. RESULTS Median (interquartile range) breast-milk iodine concentration was 90 (66-116) μg/L. About 58% had breast-milk iodine concentration <100 μg/L. Iodine supplement users (n = 13) had higher breast-milk iodine concentration than non-users (n = 49) (140 μg/L vs 71 μg/L, P = .001). Exclusively breastfeeding women at 4 months postpartum (n = 57) had lower median urinary iodine concentration (85 μg/L vs 133 μg/L, P = .004) and higher thyroglobulin serum concentration (22.3 μg/L vs 11.8 μg/L, P = .032) than non-exclusively breastfeeding women (n = 25). Concentrations of thyroid hormones were unaffected. CONCLUSIONS This pilot study suggests that lactating women in southwest Sweden present mildly inadequate iodine intake, mainly among non-iodine supplement users and exclusively breastfeeding mothers. Studies on the coverage of the iodine fortification program in breastfeeding women are warranted.
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Affiliation(s)
- Sofia Manousou
- Institute of MedicineSahlgrenska AcademyUniversity of GothenburgSahlgrenska University HospitalGothenburgSweden
- Frölunda Specialist HospitalVästra FrölundaSweden
| | - Hanna Augustin
- Institute of MedicineSahlgrenska AcademyUniversity of GothenburgSahlgrenska University HospitalGothenburgSweden
- Department of Internal Medicine and Clinical NutritionSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Robert Eggertsen
- Institute of MedicineSahlgrenska AcademyUniversity of GothenburgSahlgrenska University HospitalGothenburgSweden
- School of Public Health and Community MedicineSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Lena Hulthén
- Institute of MedicineSahlgrenska AcademyUniversity of GothenburgSahlgrenska University HospitalGothenburgSweden
- Department of Internal Medicine and Clinical NutritionSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Helena Filipsson Nyström
- Institute of MedicineSahlgrenska AcademyUniversity of GothenburgSahlgrenska University HospitalGothenburgSweden
- Department of EndocrinologySahlgrenska University HospitalGothenburgSweden
- The Wallenberg Center for Molecular and Translational MedicineSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
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Delshad H, Azizi F. Iodine nutrition in pregnant and breastfeeding women: sufficiency, deficiency, and supplementation. Hormones (Athens) 2020; 19:179-186. [PMID: 31776808 DOI: 10.1007/s42000-019-00160-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Accepted: 11/12/2019] [Indexed: 10/25/2022]
Abstract
Iodine is a micronutrient used by the thyroid gland to produce thyroid hormones, which manage different aspects of body metabolism. Humans depend on exogenous sources of iodine to maintain the normal concentration of thyroid hormones. Pregnancy alters iodine turnover and is associated with significant changes in thyroid function. Daily iodine requirement during pregnancy increases to 250 μg, compared with 150 μg for nonpregnant women. According to recent guidelines of scientific organizations, to improve maternal thyroid status and to prevent child neurocognitive defects, all pregnant and breastfeeding women should take 150 μg of iodine supplementation, not only in iodine-deficient regions but also in iodine-sufficient areas. However, some recent studies have confirmed that iodine supplementation of mildly iodine-deficient pregnant women has no clear benefits as concerns maternal thyroid function or child neurodevelopment.
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Affiliation(s)
- Hossein Delshad
- Micronutrient Research Office, Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Velenjak, Parvaneh Avenue No. 24, Research Institute for Endocrine Sciences, Tehran, Islamic Republic of Iran.
| | - Fereidoun Azizi
- Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Islamic Republic of Iran
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Wang Z, Sparling M, Wang KC, Arbuckle TE, Fraser W. Perchlorate in human milk samples from the maternal-infant research on environmental chemicals study (MIREC). Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2019; 36:1837-1846. [DOI: 10.1080/19440049.2019.1668968] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Zhongwen Wang
- Bureau of Chemical Safety, Food Directorate, Health Product and Food Branch, Health Canada, Ottawa, ON, Canada
| | - Melissa Sparling
- Bureau of Chemical Safety, Food Directorate, Health Product and Food Branch, Health Canada, Ottawa, ON, Canada
| | - Kuan Chiao Wang
- Bureau of Food Surveillance and Science Integration, Food Directorate, Health Product and Food Branch, Health Canada, Ottawa, ON, Canada
| | - Tye E. Arbuckle
- Population Studies Division, Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, ON, Canada
| | - William Fraser
- Departement D'obstetrique et gynecologie, Centre de recherche du Centre hospitalier universitaire de Sherbrooke, Sherbrooke, QC, Canada
- Sainte Justine University Hospital Research Center, University of Montreal, Montreal, QC, Canada
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11
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Lehmann GM, LaKind JS, Davis MH, Hines EP, Marchitti SA, Alcala C, Lorber M. Environmental Chemicals in Breast Milk and Formula: Exposure and Risk Assessment Implications. ENVIRONMENTAL HEALTH PERSPECTIVES 2018; 126:96001. [PMID: 30187772 PMCID: PMC6375394 DOI: 10.1289/ehp1953] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 07/27/2018] [Accepted: 07/27/2018] [Indexed: 05/19/2023]
Abstract
BACKGROUND Human health risk assessment methods have advanced in recent years to more accurately estimate risks associated with exposure during childhood. However, predicting risks related to infant exposures to environmental chemicals in breast milk and formula remains challenging. OBJECTIVES Our goal was to compile available information on infant exposures to environmental chemicals in breast milk and formula, describe methods to characterize infant exposure and potential for health risk in the context of a risk assessment, and identify research needed to improve risk analyses based on this type of exposure and health risk information. METHODS We reviewed recent literature on levels of environmental chemicals in breast milk and formula, with a focus on data from the United States. We then selected three example publications that quantified infant exposure using breast milk or formula chemical concentrations and estimated breast milk or formula intake. The potential for health risk from these dietary exposures was then characterized by comparison with available health risk benchmarks. We identified areas of this approach in need of improvement to better characterize the potential for infant health risk from this critical exposure pathway. DISCUSSION Measurements of chemicals in breast milk and formula are integral to the evaluation of risk from early life dietary exposures to environmental chemicals. Risk assessments may also be informed by research investigating the impact of chemical exposure on developmental processes known to be active, and subject to disruption, during infancy, and by analysis of exposure-response data specific to the infant life stage. Critical data gaps exist in all of these areas. CONCLUSIONS Better-designed studies are needed to characterize infant exposures to environmental chemicals in breast milk and infant formula as well as to improve risk assessments of chemicals found in both foods. https://doi.org/10.1289/EHP1953.
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Affiliation(s)
- Geniece M Lehmann
- Office of Research and Development (ORD), U.S. Environmental Protection Agency (EPA), Research Triangle Park, North Carolina, USA
| | - Judy S LaKind
- LaKind Associates, LLC, Catonsville, Maryland, USA
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Matthew H Davis
- Office of Children's Health Protection, U.S. EPA, Washington, District of Columbia, USA
| | - Erin P Hines
- Office of Research and Development (ORD), U.S. Environmental Protection Agency (EPA), Research Triangle Park, North Carolina, USA
| | - Satori A Marchitti
- Oak Ridge Institute for Science and Education (ORISE), ORD, U.S. EPA, Athens, Georgia, USA
| | - Cecilia Alcala
- Association of Schools and Programs of Public Health (ASPPH), ORD, U.S. EPA, Washington, District of Columbia, USA
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12
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Abstract
Because infants are born with small amounts of stored intrathyroidal iodine, they depend on human-milk iodine for normal physical and neurologic growth and development. The mammary gland concentrates iodide; however, there is a lack of consensus on the concentrations of breast-milk iodine necessary to achieve equilibrium in the infant. The objectives of the present review are to consider trends in breast-milk iodine concentrations over the course of lactation, to determine which maternal factors or interventions influence breast-milk iodine concentrations, to examine the association between breast-milk iodine concentrations and infant iodine status, and to identify how newer data contribute to the literature and inform recommendations for achieving optimal breast-milk iodine concentrations. A systematic search of the published literature was undertaken by using the US National Library of Medicine's MEDLINE/PubMed bibliographic search engine. Observational and intervention studies were included if the research was original, the study had not been included in a previous review, and iodine concentration in human milk was measured at ≥1 time point during the first 12 mo of lactation. Results of the systematic review indicate that breast-milk iodine concentrations vary widely between populations but are highest in colostrum and decrease gradually throughout the lactation period. Included studies did not replicate earlier findings of an inverse correlation between breast-milk iodine and perchlorate concentrations. Supplementation with high-dose or daily iodine during lactation was effective in increasing breast-milk iodine concentrations with some evidence of a dose-response relationship, which is consistent with findings of earlier supplementation trials in pregnancy and lactation. Although additional and globally representative research is needed, data suggest that breast-milk iodine concentrations in the range of 150 μg/L during the first 6 mo of lactation would achieve or exceed infant iodine equilibrium and prevent the developmental consequences of iodine deficiency.
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Affiliation(s)
- Daphna K Dror
- US Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA
| | - Lindsay H Allen
- US Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA
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13
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Henjum S, Lilleengen AM, Aakre I, Dudareva A, Gjengedal ELF, Meltzer HM, Brantsæter AL. Suboptimal Iodine Concentration in Breastmilk and Inadequate Iodine Intake among Lactating Women in Norway. Nutrients 2017; 9:E643. [PMID: 28640217 PMCID: PMC5537763 DOI: 10.3390/nu9070643] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/15/2017] [Accepted: 06/17/2017] [Indexed: 11/24/2022] Open
Abstract
Breastfed infants depend on sufficient maternal iodine intake for optimal growth and neurological development. Despite this, few studies have assessed iodine concentrations in human milk and there is currently no published data on iodine status among lactating women in Norway. The aim of this study was to assess iodine concentrations in breast milk (BMIC) in lactating women and estimate iodine intake. Five Mother and Child Health Centres in Oslo were randomly selected during 2016, and 175 lactating women between 2nd and 28th weeks postpartum participated. Each of the women provided four breastmilk samples which were pooled and analysed for iodine concentrations. Participants also provided information on iodine intake from food and supplements covering the last 24 h and the habitual iodine intake (food frequency questionnaire). The median (p25, p75 percentiles) BMIC was 68 (45, 98) µg/L and 76% had BMIC <100 µg/L. Only 19% had taken an iodine-containing supplement during the last 24 h. The median 24 h iodine intake from food (p25, p75) was 121 (82, 162) µg/day and the total intake (food and supplements) was 134 (95, 222) µg/day. The majority of lactating women had suboptimal BMIC and inadequate intake of iodine from food and supplements.
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Affiliation(s)
- Sigrun Henjum
- Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University, College of Applied Sciences, Oslo 0310, Norway.
| | - Anne Marie Lilleengen
- Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University, College of Applied Sciences, Oslo 0310, Norway.
| | - Inger Aakre
- Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University, College of Applied Sciences, Oslo 0310, Norway.
| | - Anna Dudareva
- Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University, College of Applied Sciences, Oslo 0310, Norway.
| | - Elin Lovise Folven Gjengedal
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Aas 1433, Norway.
| | - Helle Margrete Meltzer
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo 0403, Norway.
| | - Anne Lise Brantsæter
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo 0403, Norway.
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14
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Dold S, Zimmermann MB, Aboussad A, Cherkaoui M, Jia Q, Jukic T, Kusic Z, Quirino A, Sang Z, San Luis TO, Vandea E, Andersson M. Breast Milk Iodine Concentration Is a More Accurate Biomarker of Iodine Status Than Urinary Iodine Concentration in Exclusively Breastfeeding Women. J Nutr 2017; 147:528-537. [PMID: 28228508 DOI: 10.3945/jn.116.242560] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 11/06/2016] [Accepted: 01/23/2017] [Indexed: 11/14/2022] Open
Abstract
Background: Iodine status in populations is usually assessed by the median urinary iodine concentration (UIC). However, iodine is also excreted in breast milk during lactation; thus, breast milk iodine concentration (BMIC) may be a promising biomarker of iodine nutrition in lactating women. Whether the mammary gland can vary fractional uptake of circulating iodine in response to changes in dietary intake is unclear.Objective: We evaluated UIC and BMIC as biomarkers for iodine status in lactating women with a wide range of iodine intakes.Methods: We recruited 866 pairs of lactating mothers and exclusively breastfed infants from 3 iodine-sufficient study sites: Linfen, China (n = 386); Tuguegarao, Philippines (n = 371); and Zagreb, Croatia (n = 109). We also recruited iodine-deficient lactating women from Amizmiz, Morocco (n = 117). We collected urine and breast milk samples and measured UIC and BMIC.Results: In the 3 iodine-sufficient sites, a pooled regression analysis of the estimated iodine excretion revealed higher fractional iodine excretion in breast milk than in urine at borderline low iodine intakes. In contrast, in the iodine-deficient site in Morocco, a constant proportion (∼33%) of total iodine was excreted into breast milk.Conclusions: In iodine-sufficient populations, when iodine intake in lactating women is low, there is increased partitioning of iodine into breast milk. For this reason, maternal UIC alone may not reflect iodine status, and BMIC should also be measured to assess iodine status in lactating women. Our data suggest a BMIC reference range (2.5th and 97.5th percentiles) of 60-465 μg/kg in exclusively breastfeeding women. This trial was registered at clinicaltrials.gov as NCT02196337.
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Affiliation(s)
- Susanne Dold
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland;
| | - Michael B Zimmermann
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.,Iodine Global Network, Ottawa, Canada
| | | | - Mohamed Cherkaoui
- Laboratory of Human Ecology, Faculty of Sciences Semlalia, Cadi Ayyad University, Marrakesh, Morocco
| | - Qingzhen Jia
- Shanxi Institute for Prevention and Treatment of Endemic Disease, Linfen, China
| | - Tomislav Jukic
- Department of Nuclear Medicine and Oncology, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Zvonko Kusic
- Department of Nuclear Medicine and Oncology, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Antonio Quirino
- St. Luke's Medical Center, Quezon City, Manila, Philippines; and
| | - Zhongna Sang
- Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | | | - Elena Vandea
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Maria Andersson
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.,Iodine Global Network, Ottawa, Canada
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15
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Abstract
Perchlorate is an endocrine-disrupting chemical that interferes with the normal functioning of the thyroid gland. Maternal thyroid dysfunction during gestation may alter fetal brain development. Perchlorate contamination is widespread: it is present in the body of all Americans tested and the majority of foods tested. The main sources of food contamination appear to be hypochlorite bleach, a disinfectant and sanitizer, that when poorly managed quickly degrades to perchlorate and perchlorate-laden plastic food packaging for dry food or localized contamination from manufacturing or processing of the chemical. Eliminating perchlorate from food packaging and improving bleach management, such as reducing concentration and storage time and temperature, would result in reduced perchlorate contamination of food and water.
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16
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Jorgensen A, O'Leary P, James I, Skeaff S, Sherriff J. Assessment of Breast Milk Iodine Concentrations in Lactating Women in Western Australia. Nutrients 2016; 8:nu8110699. [PMID: 27827913 PMCID: PMC5133086 DOI: 10.3390/nu8110699] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 10/26/2016] [Accepted: 11/01/2016] [Indexed: 11/16/2022] Open
Abstract
Breast-fed infants may depend solely on an adequate supply of iodine in breast milk for the synthesis of thyroid hormones which are essential for optimal growth and cognitive development. This is the first study to measure breast milk iodine concentration (BMIC) among lactating women in Western Australian (n = 55). Breast milk samples were collected between 2014 and 2015 at a mean (±SD) of 38.5 (±5.5) days post-partum. The samples were analysed to determine median BMIC and the percentage of samples with a BMIC < 100 µg/L, a level considered adequate for breast-fed infants. The influence of (a) iodine-containing supplements and iodised salt use and (b) consumption of key iodine-containing foods on BMIC was also examined. The median (p25, p75) BMIC was 167 (99, 248) µg/L and 26% of samples had a BMIC < 100 µg/L. Overall, BMIC tended to be higher with iodine-containing supplement usage (ratio 1.33, 95% confidence interval (CI) (1.04, 1.70), p = 0.030), cow's milk consumption (ratio 1.66, 95% CI (1.23, 2.23), p = 0.002) and lower for Caucasians (ratio 0.61, 95% CI (0.45, 0.83), p = 0.002), and those with secondary school only education (ratio 0.66, 95% CI (0.46, 0.96), p = 0.030). For most women, BMIC was adequate to meet the iodine requirements of their breast-fed infants. However, some women may require the use of iodine-containing supplements or iodised salt to increase BMIC to adequate levels for optimal infant nutrition.
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Affiliation(s)
- Anita Jorgensen
- School of Public Health, Curtin University, Perth 6102, Australia.
| | - Peter O'Leary
- Faculty of Health Sciences, Curtin University, Perth 6102, Australia.
| | - Ian James
- Institute for Immunology & Infectious Diseases, Murdoch University, Murdoch 6150, Australia.
| | - Sheila Skeaff
- Department of Human Nutrition, University of Otago, Dunedin 9054, New Zealand.
| | - Jillian Sherriff
- School of Public Health, Curtin University, Perth 6102, Australia.
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17
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Zhang T, Ma Y, Wang D, Li R, Chen X, Mo W, Qin X, Sun H, Kannan K. Placental transfer of and infantile exposure to perchlorate. CHEMOSPHERE 2016; 144:948-954. [PMID: 26432537 DOI: 10.1016/j.chemosphere.2015.09.073] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 09/17/2015] [Accepted: 09/18/2015] [Indexed: 06/05/2023]
Abstract
Fetuses and infants are vulnerable to perchlorate toxicity. We assessed fetal and infantile exposure to perchlorate in two Chinese cities (Nanchang and Tianjin). Perchlorate was widely found (82%-100%) in breast milk, dissolved infant formula, infants' urine, maternal and cord blood samples. Perchlorate levels in infants' urine (mean ± standard deviation: 22.4 ± 35.6 ng mL(-1)), breast milk (36.6 ± 48.1 ng mL(-1)), and cord blood (3.18 ± 3.83 ng mL(-1)) samples collected from Nanchang and Tianjin were approximately an order of magnitude higher than those reported for the U.S. Perchlorate concentrations in cord blood were comparable to that in maternal blood, indicating that perchlorate is transferred from mother to fetus through placenta. Among all infants providing urine samples, the average daily intake of perchlorate (DOSEU) was estimated to be 1.17 ± 1.57 μg kg(-1) bw d(-1), and 40% of these infants had DOSEU exceeding the RfD (0.7 μg kg(-1) bw d(-1)) recommended by U.S. EPA. However, approximately 70% of exclusively breast-fed infants had perchlorate exposure dose via breast milk exceeding the RfD. For breast-fed infants, breast milk was the overwhelmingly predominant exposure pathway; while infant formula and indoor dust ingestion were major perchlorate exposure sources for formula-fed infants. To our knowledge, this is the first report to assess the fetal and infantile exposure to perchlorate in China.
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Affiliation(s)
- Tao Zhang
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-Sen University), Guangzhou 510275, China; College of Environmental Sciences and Engineering, Nankai University, Tianjin 300071, China.
| | - Yufang Ma
- College of Environmental Sciences and Engineering, Peking University, Beijing, China
| | - Dou Wang
- College of Environmental Sciences and Engineering, Nankai University, Tianjin 300071, China
| | - Rudan Li
- College of Environmental Sciences and Engineering, Nankai University, Tianjin 300071, China
| | - Xiaojia Chen
- College of Environmental Sciences and Engineering, Nankai University, Tianjin 300071, China
| | - Weiwen Mo
- College of Environmental Sciences and Engineering, Nankai University, Tianjin 300071, China
| | - Xiaolei Qin
- College of Environmental Sciences and Engineering, Nankai University, Tianjin 300071, China; Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin 300071, China
| | - Hongwen Sun
- College of Environmental Sciences and Engineering, Nankai University, Tianjin 300071, China; Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin 300071, China.
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Albany, NY 12201, USA
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18
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Nazeri P, Mirmiran P, Shiva N, Mehrabi Y, Mojarrad M, Azizi F. Iodine nutrition status in lactating mothers residing in countries with mandatory and voluntary iodine fortification programs: an updated systematic review. Thyroid 2015; 25:611-20. [PMID: 25811835 DOI: 10.1089/thy.2014.0491] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND The aim of this review is to assess data available on iodine nutrition status in lactating mothers residing in countries with mandatory and voluntary iodine fortification programs and/or iodine supplementation. SUMMARY A systematic review was conducted by searching articles published between 1964 and 2013 in Pub Med, ISI Web, and Cochrane Library using iodine nutrition, lactation, iodine supplementation, and iodine fortification as keywords for titles and/or abstracts. Relevant articles were included if they reported urinary iodine concentration (UIC) in lactating mothers and, if determined, the type of iodine fortification program and/or iodine supplementation. Forty-two studies met the inclusion criteria. Among these, 21 studies assessed lactating mothers in countries with a mandatory iodine fortification program, 17 studies were from countries with voluntary and/or without iodine fortification programs, and four studies assessed iodine nutrition status in lactating mothers undergoing iodine supplementation. Among countries with mandatory iodine fortification programs, the range of salt iodization level in lactating mothers with a UIC <100 μg/L was between 8 and 40 ppm, whereas among lactating mothers with UIC >100 μg/L, it was between 15 and 60 ppm. Levels of UIC <100 μg/L were observed among lactating women in India, Denmark, Mali, New Zealand, Australia, Slovakia, Sudan, and Turkey, whereas in countries such as Chile, Iran, Mongolia, New Guinea, and Nigeria, the median or mean of UIC was >100 μg/L. There was a median or mean UIC <100 μg/L in nearly all lactating mothers residing in countries where implementation of universal salt iodization program was voluntary, including Switzerland, Australia, New Zealand, Ireland, and Germany. However, in some countries with voluntary iodine fortification programs, such as the United States, Spain, and Japan, a mean or median UIC of >100 μg/L has been reported. CONCLUSIONS Although universal salt iodization is still the most feasible and cost-effective approach for iodine deficiency control in pregnant and lactating mothers, UIC in lactating mothers of most countries with voluntary programs and in areas with mandatory iodine fortification is still within the iodine deficiency range, indicating that iodine supplementation in daily prenatal vitamin/mineral supplements in lactating mothers is warranted. However, further investigations are still recommended in this regard.
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Affiliation(s)
- Pantea Nazeri
- 1Nutrition and Endocrine Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- 2Obesity Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Parvin Mirmiran
- 1Nutrition and Endocrine Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- 2Obesity Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Niloofar Shiva
- 3Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Yadollah Mehrabi
- 4Department of Epidemiology, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mehdi Mojarrad
- 3Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fereidoun Azizi
- 3Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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19
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Abstract
O₂-generating reactions are exceedingly rare in biology and difficult to mimic synthetically. Perchlorate-respiring bacteria enzymatically detoxify chlorite (ClO₂(-) ), the end product of the perchlorate (ClO(4)(-) ) respiratory pathway, by rapidly converting it to dioxygen (O₂) and chloride (Cl(-)). This reaction is catalyzed by a heme-containing protein, called chlorite dismutase (Cld), which bears no structural or sequence relationships with known peroxidases or other heme proteins and is part of a large family of proteins with more than one biochemical function. The original assumptions from the 1990s that perchlorate is not a natural product and that perchlorate respiration might be confined to a taxonomically narrow group of species have been called into question, as have the roles of perchlorate respiration and Cld-mediated reactions in the global biogeochemical cycle of chlorine. In this chapter, the chemistry and biochemistry of Cld-mediated O₂generation, as well as the biological and geochemical context of this extraordinary reaction, are described.
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Affiliation(s)
- Jennifer L DuBois
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA,
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20
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Yang B, Zhang M, Kanyanee T, Stamos BN, Dasgupta PK. An Open Tubular Ion Chromatograph. Anal Chem 2014; 86:11554-61. [DOI: 10.1021/ac503249t] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Bingcheng Yang
- Department
of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States
- School
of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Min Zhang
- Department
of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States
| | - Tinakorn Kanyanee
- Department
of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States
- Department
of Chemistry, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Brian N. Stamos
- Department
of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States
| | - Purnendu K. Dasgupta
- Department
of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States
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21
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Scientific Opinion on the risks to public health related to the presence of perchlorate in food, in particular fruits and vegetables. EFSA J 2014. [DOI: 10.2903/j.efsa.2014.3869] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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22
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Kirk AB, Dyke JV, Ohira SI, Dasgupta PK. Relative source contributions for perchlorate exposures in a lactating human cohort. THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 443:939-943. [PMID: 23253938 DOI: 10.1016/j.scitotenv.2012.11.072] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 11/20/2012] [Accepted: 11/20/2012] [Indexed: 06/01/2023]
Abstract
Perchlorate is an iodine-uptake inhibitor and common contaminant of food and drinking water. Understanding the amount of perchlorate exposure occurring through non-water sources is essential for accurate estimates of human exposure levels, and establishment of drinking water limits for this pervasive contaminant. The study objective was to determine the amount of perchlorate intake derived from diet rather than water. Subjects provided drinking water samples, detailed fluid-intake records, 24h urine collections and four milk samples for nine days. Samples were analyzed for perchlorate by isotope dilution ion chromatography-tandem mass spectrometry. Amounts of perchlorate derived from drinking water and dietary sources were calculated for each individual. Water of local origin was found to contribute a minor fraction of perchlorate intake. Estimated fraction intake from drinking water ranged from 0 to 36%. The mean and median dose of perchlorate derived from non-water sources by lactating women was 0.18 μg/kg/day (range: 0.06 to 0.36 μg/kg/day.) Lactating women consumed more fluid (mean 2.424 L/day) than has been assumed in recent risk assessments for perchlorate. The data reported here indicate that lactating women may be exposed to perchlorate through dietary sources at markedly higher levels than estimated previously. Exposures to perchlorate from non-water sources may be higher than recent estimates, including those used to develop drinking water standards.
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Affiliation(s)
- Andrea B Kirk
- University of North Texas Health Sciences Center, USA
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23
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Leung AM, Braverman LE, He X, Heeren T, Pearce EN. Breastmilk iodine concentrations following acute dietary iodine intake. Thyroid 2012; 22:1176-80. [PMID: 23050787 PMCID: PMC3487113 DOI: 10.1089/thy.2012.0294] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Breastmilk iodine levels may vary temporally in response to recent changes in dietary iodine intake. We assessed the effect of and time to peak breastmilk iodine levels after potassium iodine ingestion, which has never been studied and is important toward interpretation of studies of breastmilk iodine measurements. METHODS Sixteen healthy lactating Boston-area women with no known thyroid disease were each given 600 μg oral potassium iodide (KI) (456 μg iodine) after an overnight fast. Iodine was measured in breastmilk and urine at baseline and hourly for 8 hours following iodine intake. All dietary iodine ingested during the study period was also measured. RESULTS Mean age of mothers was 30.2±4.1 (SD) years. Median (interquartile range [IQR]) baseline breastmilk and urine iodine levels were 45.5 μg/L (IQR 34.5-169.0) and 67.5 μg/L (IQR 57.5-140.0), respectively. Following 600 μg KI administration, median increase in breastmilk iodine levels above baseline was 280.5 μg/L (IQR 71.5-338.0), and median peak breastmilk iodine concentration was 354 μg/L (IQR 315-495). Median time to peak breastmilk iodine levels following KI administration was 6 hours (IQR 5-7). Dietary iodine sources provided an additional 36-685 μg iodine intake during the 8-hour study. CONCLUSIONS Following ingestion of 600 μg KI, there is a measurable rise in breastmilk iodine concentrations, with peak levels occurring at 6 hours. These findings strongly suggest that breastmilk iodine concentrations should be interpreted in relation to recent iodine intake.
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Affiliation(s)
- Angela M Leung
- Section of Endocrinology, Diabetes, and Nutrition, Boston Medical Center, School of Medicine, Boston University, Boston, Massachusetts 02118, USA.
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24
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Leung AM, Braverman LE, He X, Schuller KE, Roussilhes A, Jahreis KA, Pearce EN. Environmental perchlorate and thiocyanate exposures and infant serum thyroid function. Thyroid 2012; 22:938-43. [PMID: 22827469 PMCID: PMC3429284 DOI: 10.1089/thy.2012.0058] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Breastfed infants rely on maternal iodine for thyroid hormone production required for neurodevelopment. Dietary iodine among women of childbearing age in the United States may be insufficient. Perchlorate (competitive inhibitor of the sodium/iodide symporter [NIS]) exposure is ubiquitous. Thiocyanate, from cigarettes and diet, is a weaker NIS inhibitor. Environmental perchlorate and thiocyanate exposures could decrease breast milk iodine by competitively inhibiting NIS in lactating breasts (thus impairing infants' iodine availability), and/or infants' thyroidal NIS to directly decrease infant thyroid function. The current study assessed the relationships between environmental perchlorate and thiocyanate exposures and infant serum thyroid function. METHODS Iodine, perchlorate, and thiocyanate in breast milk, maternal and infant urine, and infant serum thyroid function tests were cross-sectionally measured in Boston-area women and their 1-3 month-old breastfed infants. Univariate and multivariable analyses assessed relationships between iodine, perchlorate, thiocyanate, thyroid-stimulating hormone (TSH), and free thyroxine (FT4) levels. RESULTS In 64 mothers and infants, median (range) iodine levels were 45.6 μg/L (4.3-1080) in breast milk, 101.9 μg/L (27-570) in maternal urine, and 197.5 μg/L (40-785) in infant urine. Median perchlorate concentrations were 4.4 μg/L (0.5-29.5) in breast milk, 3.1 μg/L (0.2-22.4) in maternal urine, and 4.7 μg/L (0.3-25.3) in infant urine. There were no correlations between infant TSH or FT4 and iodine, perchlorate, and thiocyanate levels in breast milk, maternal urine, and infant urine. In multivariable analyses, perchlorate and thiocyanate levels in breast milk, maternal urine, and infant urine were not significant predictors of infant TSH or FT4. CONCLUSIONS Boston-area mothers and their breastfed infants are generally iodine sufficient. Although environmental perchlorate and thiocyanate are ubiquitous, these results do not support the concern that maternal and infant environmental perchlorate and thiocyanate exposures affect infant thyroid function.
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Affiliation(s)
- Angela M Leung
- Section of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, 88 East Newton St., Boston, MA 02118, USA.
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