The Behavior Of Thyroid Hormones In A Population Exposed To Mercury And Selenium, Which Inhabit A Municipality Located In The Western Amazon, In Brazil

Objective: To investigate the behavior of thyroid hormones in a population exposed to mercury and selenium, which lives in a municipality located in the Western Amazon, in Brazil. Methodology: Observational, descriptive, cross-sectional study, conducted with 141 people, distributed by neighborhoods based on the epidemiological study of clusters that occurred randomly in 21 neighborhoods. Blood was the material used to analyze total Hg, total Se and TSH and free T4. In addition, hair was used only for the analysis of total Hg.Results: The researched population shows average levels of total Hg in blood and hair samples above the biological limits of normality recommended by the WHO. In addition, the Se deficiency was not identified in the population sample of the studied municipality, that is, there is availability of the mineral in the region. The results of the free T4 hormone in the blood, in comparison with the concentrations of total Hg and total Se, do not seem to have produced changes in the averages of the studied sample, this finding suggests that the studied population may be exposed to the mineral in a recent or acute form. Conclusion: high levels of total Hg in the blood and hair in the population sample confirm human exposure. In addition, this study acutely identified the population's health risk in relation to the presence of Hg in the body and the thyroid gland was impaired in relation to the synthesis of free T4 hormone in prolonged exposure to the metal, even in the face of the high presence of Se in the diet of the studied population.