Methylmercury human exposure in riverine villages of Tapajos basin, Pará State, Brazil

Evaluation of total human exposure to mercury and methylmercury was effected in riverine villages along the Tapajos river and in the metropolitan area of Belem city, state of Para, Brazil, by using total mercury and methylmercury concentrations in hair samples in 1994 and 1995. It was observed that average concentrations of total mercury are in a range from 2 ± 1µg/g-1 to 20.5 ± 12.1µg/g-1. While methylmercury average concentration varies from 1.4 ± 0.7µg/g-1 to 18.5 ± 11µg/g-1. These results confirm mercury contamination in the Tapajos river and possible appearance of mercury intoxication symptoms, and recommends the monitoring of compounds in hair samples as well as the need for epidemiological and clinical studies for human health prevention and control of mercury intoxication.Avaliou-se a exposição humana ao metilmercúrio e ao mercúrio total em comunidades ribeirinhas do rio Tapajós e da região metropolitana de Belém, no Estado do Pará, Brasil, através da determinação de mercúrio total e metilmercúrio em amostras de cabelo nos anos de 1994 e 1995. Observou-se que as concentrações médias de mercúrio total variaram de 2 ± 1µg/g-1 a 20,5 ± 12,1µg/g-1, enquanto que as concentrações médias de metilmercúrio variaram de 1,4 ± 0,7µg/g-1 a 18,5 ± 11µg/g-1. Estes resultados confirmam a contaminação mercurial na região do rio Tapajós, admitem a possibilidade do aparecimento de sinais e sintomas de intoxicação mercurial e recomendam a manutenção da monitorização do mercúrio total e do metilmercúrio nas amostras de cabelo, bem como a necessidade de estudos clínico-epidemiológicos para implantação de medidas de prevenção e controle da intoxicação mercurial

Total mercury in hair samples of inhabitants of Tapajós river, Pará State, Brazil

This study evaluates human exposure to methylmercury in fishermen and their families in four villages on the Tapajós river: Rainha, Barreiras, São Luís do Tapajós and Paraná-Mirim. Hair analyses were performed with atomic absorption spectophotometry. Total hair mercury levels varied between 2.9mg/g and 71.5mg/g. Paraná-Mirim showed the lowest level. The highest level was found in São Luís do Tapajós and Barreiras. The hair mercury was six to seven times higher than the established safe limit of 10mg/g. No statistically significant difference was found between the mean level of total mercury taken from the inhabitants living downstream and upstream in Itaituba village (p > 0.05). These results confirm that human exposure to methylmercury is occurring on the Tapajós river and suggest that continued fish ingestion in that region is a potential risk factor for the appearance of symptoms and signs of Minamata disease. An immediate epidemiological survey program is recommended.Este estudo avalia a contaminação mercurial em comunidades de pescadores em quatro localidades nas margens do rio Tapajós: Rainha, Barreiras, São Luís do Tapajós e Paraná-Mirim. Análises toxocológicas das amostras de cabelo foram realizadas por espectofotometria de absorção atômica. Os níveis de mercúrio total em amostras de cabelo variaram entre 2,9µg/g e 71,5µg/g. Os valores mais baixos foram encontrados na comunidade de Paraná-Mirim. Os mais elevados, em São Luís do Tapajós e Barreiras, cerca de seis a sete vezes superiores ao valor estabelecido. As diferenças entre as concentrações médias de mercúrio total nas amostras, coletadas em populações ribeirinhas, a montante e a jusante do rio Tapajós em Itaituba, não apresentaram significância estatística (p > 0,05). Conclui-se que a exposição humana ao mercúrio por ingestão de peixes contaminados constitui risco potencial para o aparecimento de sintomas e sinais da doença de Minamata, o que recomenda a manutenção de um programa de vigilância epidemiológica

Comparative study of human exposure to mercury in riverside communities in the Amazon region

Four populations in the Amazon area were selected for a comparative study of mercury-exposed and non-exposed populations: São Luiz do Tapajós, Barreiras, Panacauera, and Pindobal Grande. The highest mercury levels in human hair samples were found in São Luiz do Tapajós and Barreiras, greatly exceeding the limits established by the World Health Organization. Panacauera showed an intermediate level below 9 µg/g. This was the first comparative and simultaneous evaluation of mercury exposure in the Amazon area. Also, thanks to this type of monitoring, we were able to eliminate the uncertainties about the reference dose. On the basis of these data, we can conclude that the mercury levels detected in exposed populations of the Tapajós River basin may be dangerous not only because they are above the World Health Organization limits, but also because the simultaneous mercury detection in non-exposed populations with similar characteristics provided a valid control and revealed lower mercury levels. Our results support the importance of continuous monitoring in both exposed and non-exposed populations

Hormônios tireoidianos, anti-TPO e concentrações de mercúrio total na avaliação da disfunção glandular em população ribeirinha da Amazônia

There is evidence that mercury accumulation in the thyroid can cause endocrine and immune disorders. Riverside populations of the Amazon with a history of prolonged exposure to mercury have been investigated for neurological damage, but little is known about the hormonal disorders and specific immune thyroid. The objective of this study is to verify the existence of association between the total mercury concentrations in hair samples and concentrations of thyroid hormones and the anti-TPO antibody. The study included 86 riverine from Tapajos region mercury exposed to long-term. Participated this study men and women aged between 14 and 54 years, residents in place for more than five years. Measurements of serum hormone concentrations (TSH, T3 and free T4) and Anti-TPO titles were taken by enzyme immunoassay. Total mercury (THg) in hair samples was measured by atomic absorption spectrophotometry by cold vapor technique. Hormonal dysfunction occurred in 10.3% with an increase of T3, 2.3% with a reduction of T4L, 3.4% decrease in TSH and 4.6% with increased TSH expressed that the maximum value of 8.9 μU/m. Anti-TPO titles were normal in all participants. There was no correlation of hormonal markers (TSH, T3 and T4L) or the Anti-TPO with mercury levels. The results showed that THg concentrations in hair, serum TSH and anti-TPO titles were not influenced by sex; that hormonal changes in thyroid studied riparian not associated with the levels of THg suggesting the interference of protector factors on thyroid function.Há evidências que o acúmulo de mercúrio na tireóide pode causar distúrbios endócrinos e imunes. Populações ribeirinhas da Amazônia com histórico de exposição prolongada ao mercúrio têm sido investigadas para danos neurológicos, porém, pouco se conhece sobre os distúrbios hormonais e imunes específicos da tireóide. O objetivo deste estudo foi verificar a associação das concentrações de HgT em amostras de cabelo com as concentrações dos hormônios tireoidianos e com a titulação do anticorpo anti-TPO. O estudo incluiu 86 ribeirinhos do Tapajós com exposição em longo prazo ao mercúrio. Participaram homens e mulheres com idade entre 14 e 54 anos, residentes no local por mais de cinco anos. As concentrações hormonais no soro (TSH, T3 e T4 livre) e os títulos de Anti-TPO foram obtidas através de método imunoenzimático. Mercúrio total (HgT) em amostras de cabelo foi medido pela espectrofotometria de absorção atômica usando o Mercury Analyzer SP3D da Nippon Corporation. Disfunções hormonais ocorreram em 10,3% com aumento de T3, 2,3% com redução de T4L, 3,4% de redução de TSH e 4,6% com aumento de TSH que expressou o máximo valor de 8,9 μU/m. Títulos de Anti-TPO foram normais em todos os participantes. Não houve correlação dos marcadores hormonais (TSH, T3 e T4L) nem do Anti-TPO com os níveis de mercúrio. Os resultados mostraram que as concentrações de HgT em cabelo, de TSH no soro e os títulos de Anti-TPO não foram influenciados pelo sexo; que os níveis dos hormônios tireoidianos e os títulos de Anti_TPO não mostraram associação com os níveis de HgT sugerindo a interferência de fatores protetores na função tireoidiana

Anemia, parasitismo intestinal e exposição mercurial em duas comunidades ribeirinhas da Amazônia

The incidence of anemia, intestinal parasitism and mercurial exposure prevalence in two Amazon riverside communities, São Luiz of Tapajós (Tapajós River) and Igarapé-Mirim (Tocantins River), where social-economics standards are similar. Eighty hair simples, blood and stool were analyzed. The results demonstrated incidence of intestinal parasitism of 42.5% in São Luiz of Tapajós and 75,15% in Igarapé-Mirim. The hematimetrics indexes indicated incidence of anemia of 40% in São Luiz do Tapajós and 25% in Igarapé-Mirim. The medium total mercury concentrations in hair samples of the residents in São Luiz of Tapajós were 14.9 ± 6.6 µg/g in male individuals and 13,4 ± 3,4 µg/g in the females sex, while in Igarapé-Mirim they were of 2,5 ± 1,4 µg/g in the male probant and 3,5 ± 1,6 µg/g in the female one. It was observed in São Luiz do Tapajós, 82,5% of concentrations of total mercury are above the 10 µg/g, value of reference for population no exposed, while in Igarapé-Mirim, any values above these were fround values. It can be concluded that the quality of life of the riverine people analyzed is committed by the appraised factors, becoming necessary the adoption of preventive ways of educative actions in those communities by government authorities sponsor.A incidência de anemia, parasitismo intestinal e prevalência da exposição mercurial foi avaliada em duas comunidades amazônicas ribeirinhas, São Luiz do Tapajós (Rio Tapajós) e Igarapé-Mirim (Rio Tocantins) cujos padrões sócio-econômicos são semelhantes. Foram analisadas amostras de cabelo, sangue e fezes dos residentes nestas comunidades, empregando metodologia analítica oficialmente reconhecida. Oitenta amostras de cabelo, sangue e fezes foram analisadas. Os resultados demonstraram incidência média de 42,5 % de parasitose intestinal em São Luiz do Tapajós e 75,15 % em Igarapé-Mirim. Os índices hematimétricos indicaram incidência de anemia de 40 % em São Luiz do Tapajós e 25 % em Igarapé-Mirim. Os teores médios de mercúrio total nas amostras de cabelo dos residentes em São Luiz do Tapajós foram de 14,9 ± 6,6 µg/g nos indivíduos do sexo masculino e 13,4 ± 3,4 µg/g no sexo feminino, enquanto que em Igarapé-Mirim foi de 2,5 ± 1,4 µg/g na população masculina e 3,5 ± 1,6 µg/g na feminina. Observou-se que em São Luiz do Tapajós, 82 % das concentrações de mercúrio total encontram-se acima de 10µg/g, valor considerado de referência para população não exposta, enquanto que em Igarapé-Mirim, não foram encontrados valores acima destes. Pode-se concluir que a qualidade de vida dos ribeirinhos analisados é comprometida pelos fatores avaliados, tornando-se necessária à adoção de medidas preventivas e ações educadoras nestas comunidades pelas autoridades governamentais responsáveis

Biomarker release after coronary artery bypass grafting without established myocardial infarction assessed by cardiac magnetic resonance with late gadolinium enhancement

Introdução: O diagnóstico infarto do miocárdio (IAM) Tipo 5 é bastante complexo, especialmente após o surgimento de ensaios com a troponina de alta sensibilidade. Objetivo: Mensurar a liberação de biomarcadores de necrose miocárdica após cirurgia de revascularização (RM) utilizando a circulação extracorpórea (CEC) na ausência de novo realce tardio pelo gadolínio (RTG). Métodos: Neste estudo, avaliamos pacientes com doença arterial coronária estável, multiarterial, função do ventrículo esquerdo preservada, biomarcadores cardíacos basais normais e indicação formal para a cirurgia de revascularização eletiva com CEC. Eletrocardiograma, coleta de amostras de sangue para a mensuração de troponina e CKMB, e ressonância magnética cardíaca (RMC) com realce tardio pelo gadolíneo (RTG) foram efetuadas antes e após o procedimento. O diagnóstico de IM foi definido como acima de 10 vezes o percentil 99 URL, para troponina e CK-MB, respectivamente, e novo RTG pela RMC. Resultados: De 75 pacientes selecionados para RM com CEC, 69 foram analisados; destes, 54 não apresentaram RTG (IAM tipo 5 na RMC). 39 pacientes eram do sexo masculino (72,2%), com idade média de 61,3 (±8,3) anos. A pontuação média do SYNTAX Score foi de 28 (±10). Após a cirurgia, 54 (100%) pacientes tiveram um pico de troponina acima do percentil 99; destes, em 52 (96%) este pico foi maior do que 10 vezes o percentil 99. Por outro lado, 54 (100%) pacientes alcançaram pico de CK-MB acima do limite do percentil 99 e em apenas 13 (24%) foi maior do que 10 vezes o percentil 99. A troponina apresentou mediana do pico de 3,15 (2,0 - 4,9) ng/mL, 78,75x superior ao percentil 99. Conclusão: Nesta amostra estudada, a CKMB, diferentemente da troponina, teve níveis de liberação dentro dos padrões recomendados pelas diretrizes e coincidiu com ausência de realce na RMC. Estes dados permitem sugerir um maior ponto de corte de troponina para o diagnóstico do IAM relacionado ao procedimentoBackground: The diagnosis of periprocedural myocardial infarction is complex, especially after the emergence of high-sensitive markers of myocardial necrosis. Methods: In this prospective study, patients with stable multivessel coronary disease, preserved left ventricular function, normal baseline cardiac biomarkers, and formal indication for elective on-pump coronary bypass surgery (ONCAB) were evaluated. Electrocardiograms, cardiac biomarkers CKMB and troponin I (cTnI), and cardiac magnetic resonance imaging (CMR) with late gadolinium enhancement were performed before and after procedures. Myocardial infarction (MI) was defined as more than ten times the upper reference limit of the 99th percentile for cTnI and for CKMB and by the findings of new late gadolinium enhancement on CMR. We assessed the release of cardiac biomarkers in patients with no evidence of myocardial infarction on CMR. Results: From 75 patients referred to ONCAB, 69 were analyzed in this study. From these, 54 patients did not have evidence of MI on CMR. This group had 39 men (72.2%), mean age of 61.3 (± 8.3) years and a mean SYNTAX Score of 28 (± 10). After CABG, all 54 (100%) patients had a peak cTnI above the 99th percentile, and 52 (96%) had an elevation 10 times higher than the 99th percentile. Regarding CKMB, 54 (100%) patients had a peak CKMB above the 99th percentile limit, and only 13 (24%) had an elevation greater than 10 times the 99th percentile. The median value of cTnI peak was 3.15 (2.0 to 4.9) ng/mL. This represented 78.75 times the 99th percentile. Conclusion: In this sample, CKMB, unlike cTnI, had levels of release within the standards recommended by the guidelines and coincided with lack of enhancement in CMR. These data suggest a higher troponin cutoff point for the diagnosis of MI related to the procedur

Abnormal elevation of myocardial necrosis biomarkers after coronary artery bypass grafting without established myocardial infarction assessed by cardiac magnetic resonance

Abstract Background The diagnosis of peri-procedural myocardial infarction is complex, especially after the emergence of high-sensitivity markers of myocardial necrosis. Methods In this study, patients with normal baseline cardiac biomarkers and formal indication for elective on-pump coronary bypass surgery were evaluated. Electrocardiograms, cardiac biomarkers, and cardiac magnetic resonance imaging with late gadolinium enhancement were performed before and after procedures. Myocardial infarction was defined as more than ten times the upper reference limit of the 99th percentile for troponin I and for creatine kinase isoform (CK-MB) and by the findings of new late gadolinium enhancement on cardiac magnetic resonance. We assessed the release of cardiac biomarkers in patients with no evidence of myocardial infarction on cardiac magnetic resonance. Results Of 75 patients referred for on-pump coronary bypass surgery, 54 (100%) did not have evidence of myocardial infarction on cardiac magnetic resonance. However, all had a peak troponin I above the 99th percentile; 52 (96%) had an elevation 10 times higher than the 99th percentile. Regarding CK-MB, 54 (100%) patients had a peak CK-MB above the 99th percentile limit, and only 13 (24%) had an elevation greater than 10 times the 99th percentile. The median value of troponin I peak was 3.15 (1.2 to 3.9) ng/mL, which represented 78.7 times the 99th percentile. Conclusion In this study, different from CK-MB findings, troponin was significantly increased in the absence of myocardial infarction on cardiac magnetic resonance. Thus, CK-MB was more accurate than troponin I for excluding procedure-related myocardial infarction. These data suggest a higher troponin cutoff for the diagnosis of coronary bypass surgery related myocardial infarction. Clinical trial registration http://www.isrctn.com/ISRCTN09454308 . Registered 08 May 2012