Mercury Pollution and Alimentation Change through the Globalization Process in two Amazon River Communities

Background: Excess body weight and metabolic comorbidities represent a risk for the emergence of chronic diseases and premature deaths, a growing phenomenon observed in riverside communities in the Amazon. Methods: The study developed was a descriptive and analytical cohort of the risk factors predisposing to excess body weight in communities of the Tapajós valley region exposed to mercurial contamination. The sample population includes 130 adult individuals from Barreiras and 80 from São Luiz do Tapajós, of both sexes, who agreed to participate in this study. A semi-structured questionnaire was applied to obtain epidemiological and nutritional information, and validated conventional methods were used to evaluate the anthropometric parameters. Results: Total mercury in hair was measured using the atomic absorption spectrometry technique. In both communities, the prevalence of overweight was 60%, and abdominal adiposity among these individuals was higher than in those without overweight. The consumption of fish in the overweight and eutrophic groups in the inhabitants of the community of São Luiz do Tapajós differed, as well as and the average levels of mercury in the hair were higher in those who were overweight. However, this association was not observed in the community of Barreiras, where about approximately 61% of individuals, regardless of body weight, consumed little fish and in turn had low average levels of mercury in their hair. Conclusions: The evidence indicates changes in the eating habits of the studied communities, determining a nutritional imbalance through an increasing body weight gain among individuals, high BMI, and consequently the measurement of abdominal adiposity, which are factors for non-transmissible chronic diseases. Moreover, not only the excessive caloric intake and sedentary lifestyle, but also it is note, that mercurial toxicity must have contributed to affect affecting endocrine homeostasis and the physiology of metabolism; and, therefore, it is essential to seek appropriate interventions to combat public health diseases in communities exposed to mercurial contamination.