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Introduction: adequate iodine intake during pregnancy is essential for the synthesis of thyroid hormones, which are important for the physiological functions of the mother and appropriate maturation of the central nervous system of the fetus. Objective: the objective of the present study was to determine the levels of urinary iodine excretion and thyroid function, antioxidants and oxidative stress markers in pregnant women. Methods: the study was conducted on 191 pregnant women and 62 non-pregnant women who were evaluated regarding nutritional status. Analyses of urinary iodine, of oxidative stress markers and thyroid function were performed, revealing iodine insufficiency in 81 pregnant women. Results: there was no change in the thyroid stimulating hormone concentration in 89% of the pregnant women. Antithyroperoxidase antibody values were higher in the control group compared to the pregnant women's group (64.5% and 12.6%, respectively) and antithyroglobulin antibody values were also higher in the control group (11.6%). Assessment of oxidative stress revealed higher levels of advanced oxidation protein products, of total antioxidant capacity and of superoxide dismutase antioxidants in pregnant women. Classification of ioduria with respect to oxidative stress markers revealed lower α-tocopherol levels for the pregnant women with iodine insufficiency. Conclusion: on this basis, the results suggest that iodine insufficiency did not induce changes in thyroid stimulating hormone levels or antibodies and those pregnant women with adequate urinary iodine excretion had a better profile of the α-tocopherol antioxidant, indicating that iodine may play a significant role in antioxidant capacity during gestation. Resumen Introducción: la ingesta adecuada de yodo durante el embarazo es esencial para la síntesis de las hormonas tiroideas, que son importantes para las funciones fisiológicas de la madre y la maduración apropiada del sistema nervioso central del feto. Objetivo: el objetivo del presente estudio fue determinar los niveles de excreción de yodo urinario y función tiroidea, antioxidantes y marcadores de estrés oxidativo en mujeres embarazadas. Métodos: el estudio se realizó en 191 mujeres embarazadas y 62 mujeres no embarazadas que fueron evaluadas con respecto al estado nutricional. Se realizaron análisis de yodo urinario, marcadores de estrés oxidativo y función tiroidea, que revelaron insuficiencia de yodo en 81 embarazadas. Resultados: no hubo cambios en la concentración de hormona estimulante tiroidea en el 89% de las mujeres embarazadas. Los valores de anticuerpos antitiroperoxidasa fueron mayores en el grupo control en comparación con el grupo de mujeres embarazadas (64,5% y 12,6%, respectivamente) y los de anticuerpos antitiroglobulina fueron también mayores en el grupo control (11,6%). La evaluación del estrés oxidativo reveló niveles más altos de productos avanzados de proteína de oxidación, de capacidad antioxidante total y de antioxidantes de superóxido dismutasa en mujeres embarazadas. La clasificación de la yoduria con respecto a marcadores de estrés oxidativo reveló menores niveles de α-tocopherol para las mujeres embarazadas con insuficiencia de yodo. Conclusión: sobre esta base, los resultados sugieren que la insuficiencia de yodo no indujo cambios en los niveles de hormona estimulante de la tiroides o anticuerpos y las mujeres embarazadas con excreción urinaria adecuada de yodo tuvieron un mejor perfil del antioxidante α-tocopherol, lo que indica que el yodo puede desempeñar un papel significativo en la capacidad antioxidante durante la gestación.

Introduction: adequate iodine intake during pregnancy is essential for the synthesis of thyroid hormones, which are important for the physiological functions of the mother and appropriate maturation of the central nervous system of the fetus. Objective: the objective of the present study was to determine the levels of urinary iodine excretion and thyroid function, antioxidants and oxidative stress markers in pregnant women. Methods: the study was conducted on 191 pregnant women and 62 non-pregnant women who were evaluated regarding nutritional status. Analyses of urinary iodine, of oxidative stress markers and thyroid function were performed, revealing iodine insufficiency in 81 pregnant women. Results: there was no change in the thyroid stimulating hormone concentration in 89% of the pregnant women. Antithyroperoxidase antibody values were higher in the control group compared to the pregnant women's group (64.5% and 12.6%, respectively) and antithyroglobulin antibody values were also higher in the control group (11.6%). Assessment of oxidative stress revealed higher levels of advanced oxidation protein products, of total antioxidant capacity and of superoxide dismutase antioxidants in pregnant women. Classification of ioduria with respect to oxidative stress markers revealed lower α-tocopherol levels for the pregnant women with iodine insufficiency. Conclusion: on this basis, the results suggest that iodine insufficiency did not induce changes in thyroid stimulating hormone levels or antibodies and those pregnant women with adequate urinary iodine excretion had a better profile of the α-tocopherol antioxidant, indicating that iodine may play a significant role in antioxidant capacity during gestation.

Arsenic is considered a semimetal, and its wide distribution in the Earth's crust in different chemical forms, including organic and inorganic species, has a great deal of influence on the mechanisms of toxicity. Exposure to arsenic can be either through occupational practice (use of pesticides) or by the consumption of water and food containing the element. Rice is considered a fundamental constituent of the basic diet of Brazilians and is usually cultivated in flooded conditions. Such a plantation system results in an increased amount of As in the soil and hence a greater accumulation of As in the plant, which is highlighted by the inorganic species' classification as highly toxic. Besides the use of mitigation techniques to reduce the toxicological risk, monitoring the concentration of As and its chemical species in rice and rice products is required through the establishment of legislation in the area. Thus, some world organizations are conducting improved research to determine and establish acceptable concentrations of As and its chemical species in rice, e. g., in 2012, FDA researchers described a chemical speciation methodology for As in rice and rice products. Hence, the application of existing chemical speciation methods and the establishment of parameters for ensuring food security and exposure risk assessment deserve particular consideration.

Arsenic is considered a semimetal, and its wide distribution in the Earth's crust in different chemical forms, including organic and inorganic species, has a great deal of influence on the mechanisms of toxicity. Exposure to arsenic can be either through occupational practice (use of pesticides) or by the consumption of water and food containing the element. Rice is considered a fundamental constituent of the basic diet of Brazilians and is usually cultivated in flooded conditions. Such a plantation system results in an increased amount of As in the soil and hence a greater accumulation of As in the plant, which is highlighted by the inorganic species' classification as highly toxic. Besides the use of mitigation techniques to reduce the toxicological risk, monitoring the concentration of As and its chemical species in rice and rice products is required through the establishment of legislation in the area. Thus, some world organizations are conducting improved research to determine and establish acceptable concentrations of As and its chemical species in rice, e. g., in 2012, FDA researchers described a chemical speciation methodology for As in rice and rice products. Hence, the application of existing chemical speciation methods and the establishment of parameters for ensuring food security and exposure risk assessment deserve particular consideration.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Evidências sugerem uma relação entre as concentrações de elementos essenciais e tóxicos e o agravo de fatores de risco cardiometabólicos. Este estudo objetivou investigar as concentrações de zinco, cobre, selênio, arsênio, cádmio e mercúrio e suas relações com fatores de risco cardiometabólicos em adultos e idosos. Este trabalho de delineamento transversal foi realizado com 112 indivíduos de ambos os sexos, residentes no município de Natal/RN, participantes do Estudo Brazilian Usual Consumption Assessment (BRAZUCA) Natal. Foram coletados dados sociodemográficos, clínicos e estilo de vida. Avaliou-se parâmetros antropométricos (perímetro da cintura – PC e índice de adiposidade visceral – VAI), perfil glicêmico e lipídico, pressão arterial e proteína C-reativa ultra sensível (PCR-us). Foi calculado o Escore de Risco Global (ERG) e definido o risco cardiovascular. As concentrações dos elementos químicos essenciais foram medidas no plasma e, dos tóxicos, na urina, considerando a técnica de espectrometria de massas com plasma indutivamente acoplado (ICP-MS). Foram construídos modelos de regressão linear múltipla, ajustados por idade, sexo, índice de massa corporal (IMC), tabagismo e frequência de consumo de bebidas alcoólicas, para identificar a relação dos elementos químicos com os fatores de risco cardiometabólicos. Observou-se associação inversa entre o arsênio na urina e o índice de adiposidade visceral (VAI) (β -0,03, R² 18,22, p