Mercurio y trastornos del neurodesarrollo en niños: una revisión sistemática / Mercury and neurodevelopmental disorders in children: A systematic review

El mercurio es un metal tóxico que puede atravesar la placenta y la barrera hematoencefálica, y causar la interrupción de varios procesos celulares. Estudios han investigado la exposición al mercurio y trastornos en el neurodesarrollo, por lo que se requiere un análisis crítico y riguroso de esta evidencia. El objetivo de esta revisión fue evaluar la evidencia científica disponible sobre los efectos de la exposición al mercurio durante las etapas prenatal y posnatal, y su relación con el desarrollo de trastornos neuroconductuales. Se realizó una búsqueda sistemática en las bases de datos MEDLINE y ScienceDirect; los resultados se presentaron a través de tablas y síntesis narrativa. Solo 31 estudios cumplieron los criterios de elegibilidad. En general, la evidencia es limitada sobre los efectos de la exposición al mercurio y trastornos del neurodesarrollo en niños. Entre los posibles efectos reportados, se hallan problemas en el aprendizaje, autismo y trastorno por déficit de atención e hiperactividad.

Mercury is a toxic metal which can cross the placenta and the blood-brain barrier and cause the disruption of various cellular processes. Studies have investigated mercury exposure and neurodevelopmental disorders; therefore, a critical and rigorous analysis of this evidence is required. The objective of this review was to evaluate the available scientific evidence on the effects of mercury exposure during the prenatal and postnatal periods and its relationship with the development of neurobehavioral disorders. A systematic search of the MEDLINE and ScienceDirect databases was conducted; the results were presented in tables and narrative synthesis. Only 31 studies met the eligibility criteria. Overall, the evidence on the effects of mercury exposure and neurodevelopmental disorders in children is limited. Learning disabilities, autism, and attention deficit hyperactivity disorder were some of the reported potential effects.

Analysis of heavy metal pollution in Lonicerae Japonicae Flos and its health risk assessment / 中国中药杂志

In this study, the content of five heavy metals(Pb, Cd, As, Hg, and Cu) in 59 batches of Lonicerae Japonicae Flos(LJF) medicinal materials and pieces were determined by inductively coupled plasma mass spectrometry(ICP-MS). The health risk assessment was processed using the maximum estimated daily intake(EDI), target hazard quotients(THQ), and carcinogenic risks(CR) assessment models. With reference to the limit standard for heavy metal content in LJF specified in 2020 edition of Chinese Pharmacopoeia, five batches produced in Hebei were found to contain excessive Pb, and the remaining 54 batches met the specifications, with the unqualified rate of 8.47%. Comparative analysis of heavy metal content in LJF samples from three different producing areas, namely Shandong, Henan, and Hebei showed that the levels of Pb, As, and Hg in LJF from Hebei were significantly higher than those from Henan and Shandong. The samples produced in Shandong contained the highest content of Cd. The samples from Hebei contained the highest content of Cu while those from Shandong had the lowest content of Cu. As demonstrated by health risk assessment based on the EDI, THQ and CR models, these 59 batches of LJF samples did not cause significant health hazards for the exposed population, and there was no potential non-carcinogenic or carcinogenic risk. In conclusion, a few of LJF samples contained excessive heavy metals, so some measures, including controlling production environment, cultivating management mode, and optimizing processing methods, should be taken for ensuring the medication safety of LJF.

The cost of gold: Mercury contamination of fishes in a Neotropical river food web

In South America, mercury contamination due to gold mining operations is a threat to both biodiversity and human health. We examined mercury (Hg) concentrations in fishes that constitute important subsistence fisheries from mined and non-mined tributaries in the middle Mazaruni River, Guyana. Mercury concentrations and trophic food web structure (based on carbon and nitrogen stable isotopes) were characterized for primary basal sources and 39 fish species representing seven trophic guilds. Fishes collected at mined sites had higher mercury concentrations; piscivores and carnivores had the highest Hg concentrations and exhibited significant Hg biomagnification. Our results showed that medium- to large-bodied fishes commonly eaten by local people contained Hg values that exceed the World Health Organization (WHO) criteria, and pose a health concern for riverine communities along the Mazaruni River that depend on fish as their main source of protein. Further research to determine the sources of Hg contamination and how it affects human health in this neotropical river must become a top priority. In addition, more research on how Hg contamination impacts the fishes themselves and overall aquatic biodiversity is also needed in the Mazaruni River which has both high fish endemism and diversity.(AU)

Na América do Sul, a contaminação por mercúrio devido às operações de mineração de ouro é uma ameaça à biodiversidade e à saúde humana. Nós examinamos as concentrações de mercúrio (Hg) em peixes que constituem importantes pescarias de subsistência em afluentes minerados e não minerados no médio rio Mazaruni, Guiana. As concentrações de mercúrio e a estrutura trófica da teia alimentar (baseada em isótopos estáveis ​​de carbono e nitrogênio) foram caracterizadas para fontes basais primárias e 39 espécies de peixes representando sete guildas tróficas. Os peixes coletados em locais minerados tiveram maiores concentrações de mercúrio; piscívoros e carnívoros tiveram as maiores concentrações de Hg e exibiram biomagnificação significativa de Hg. Nossos resultados mostraram que peixes de corpo médio a grande comumente consumidos pela população local continham valores de Hg que excedem os critérios da Organização Mundial de Saúde (OMS) e representam uma preocupação para a saúde das comunidades ribeirinhas ao longo do rio Mazaruni que dependem dos peixes como sua principal fonte de proteína. Outras pesquisas para determinar as fontes de contaminação por Hg e como isso afeta a saúde humana neste rio neotropical devem se tornar uma prioridade. Além disso, mais pesquisas sobre como a contaminação por Hg impacta os próprios peixes e a biodiversidade aquática em geral também são necessárias no rio Mazaruni, que tem alto endemismo e diversidade de peixes.(AU)

Total mercury in wild felids occurring in protected areas in the central Brazilian Amazon

This is the first study to investigate mercury (Hg) contamination in felid species in the Brazilian Amazon. We collected 26 fur samples from wild felids of four species (Puma concolor, Panthera onca, Leopardus pardalis and Leopardus wiedii) occurring in the Mamirauá and Amanã sustainable development reserves, in the state of Amazonas. Samples were from museum specimens, except for five P. onca samples collected from free-living individuals. Total Hg concentrations ranged from 0.12 to 48.1 µg g-1. Concentrations of Hg did not differ significantly between museum specimens and live individuals of P. onca, but varied significantly among species, with significantly higher concentrations for P. onca and L. pardalis, which could be related to factors such as diet and habitat. (AU)

La amalgama dental en el futuro / Dental amalgam in the future

Las convenciones internacionales relacionadas con las posibles consecuencias ambientales del empleo del mercurio a las que ha adherido la República Argentina llevan a la paulatina desaparición de la posibilidad del empleo de este elemento. Consecuentemente, se genera la necesidad de reducir y, en última instancia, eliminar el uso de productos médicos que lo contengan, como es el caso de la amalgama dental. Se requiere de la decisión conjunta de las comunidades académica y asistencial para definir estrategias a aplicar en la reducción gradual del uso de la amalgama dental. La forma de hacerlo y la tecnología para su reemplazo aún son inciertas (AU)

International conventions related to the possible environmental consequences of the use of mercury that the Argentine Republic has subscribed lead to the gradual disappearance of the possibility of using this element. Consequently, there is a need to reduce and ultimately eliminate the use of medical products that contain it, as is the case with dental amalgam. The joint decision of academic and healthcare communities is required to define strategies to be applied in the gradual reduction of the use of dental amalgam. The way to do it and the technology for its replacement still remain uncertain (AU)

Effects of Chronic Exposure to Mercury on Angiotensin-Converting Enzyme Activity and Oxidative Stress in Normotensive and Hypertensive Rats / Efeitos da Exposição Crônica ao Mercúrio sobre a Atividade da Enzima Conversora de Angiotensina e Estresse Oxidativo em Ratos Normotensos e Hipertensos

Abstract Background: Mercury's deleterious effects are associated with increased cardiovascular risk. Objective: To determine whether chronic exposure to inorganic mercury increases the activity of angiotensin-converting enzyme and its relationship with oxidative stress in several organs and tissues. Methods: We studied male Wistar and spontaneously hypertensive rats (SHR) (3-month-old) exposed or not to HgCl2 for 30 days. At the end of treatment, we investigated the following: changes in body weight, hemodynamic parameters, angiotensin-converting enzyme (ACE) activity and oxidative stress in the heart, aorta, lung, brain and kidney in hypertensive compared to normotensive animals. A value of p < 0.05 was considered significant. Results: Chronic exposure to HgCl2 did not affect weight gain in either group. Systolic blood pressure, measured weekly, did not increase in Wistar rats but showed a small increase in SHR rats. We also observed increases in left ventricular end-diastolic pressure and ACE activity in the plasma and hearts of normotensive rats. In the SHR+Hg group, ACE activity increased in plasma but decreased in kidney, lung, heart, brain and aorta. Oxidative stress was assessed indirectly by malondialdehyde (MDA) production, which increased in Hg-treated rats in both plasma and heart. In the SHR+Hg group, MDA increased in heart and aorta and decreased in lungs and brain. Conclusion: These results suggest that chronic exposure to inorganic mercury aggravates hypertension and produces more expressive changes in ACE activity and oxidative stress in SHRs. Such exposure affects the cardiovascular system, representing a risk factor for the development of cardiovascular disorders in normotensive rats and worsening of pre-existing risks for hypertension.

Resumo Fundamento: Os efeitos deletérios do mercúrio estão associados ao risco cardiovascular aumentado. Objetivo: Determinar se a exposição crônica ao mercúrio inorgânico aumenta a atividade da enzima conversora de angiotensina e sua relação com o estresse oxidativo em vários órgãos e tecidos. Métodos: Estudamos ratos Wistar e ratos espontaneamente hipertensos (SHR) (3 meses de idade) expostos ou não a HgCl2 por 30 dias. Ao final do tratamento, investigamos: alterações de peso, parâmetros hemodinâmicos, atividade da enzima conversora de angiotensina (ECA) e estresse oxidativo no coração, aorta, pulmão, cérebro e rim de animais hipertensos comparados a animais normotensos. Um valor de p < 0,05 foi considerado significativo. Resultados: A exposição crônica ao HgCl2 não afetou o ganho de peso em nenhum dos grupos. A pressão arterial sistólica, medida semanalmente, não aumentou em ratos Wistar, mas mostrou um pequeno aumento nos ratos SHR. Também observamos aumentos na pressão diastólica final do ventrículo esquerdo e na atividade da ECA no plasma e no coração de ratos normotensos. No grupo SHR + Hg, a atividade da ECA aumentou no plasma, mas diminuiu no rim, pulmão, coração, cérebro e aorta. O estresse oxidativo foi avaliado indiretamente pela produção de MDA, que aumentou nos ratos tratados com Hg tanto no plasma quanto no coração. No grupo SHR + Hg, o MDA aumentou no coração e na aorta e diminuiu nos pulmões e no cérebro. Conclusão: Estes resultados sugerem que a exposição crônica ao mercúrio inorgânico agrava a hipertensão e produz mudanças mais expressivas na atividade da ECA e no estresse oxidativo em SHRs. Essa exposição afeta o sistema cardiovascular, representando um fator de risco para o desenvolvimento de distúrbios cardiovasculares em ratos normotensos e para piorar riscos pré-existentes para hipertensão.

Use of zebrafish ( Danio rerio ) embryos as a model to assess effects of mercury on developing skeletal muscle: a morphometric and immunohistochemical study / Uso de embriones de pez cebra ( Danio rerio ) como modelo para evaluar los efectos del mercurio en el desarrollo del músculo esquelético: un estudio morfométrico e inmunohistoquímico

Exposure to mercury in the environment continues to be a significant worldwide concern, especially for developing embryos and fetuses. While extensive research effort has focused on the effects of mercury on the developing nervous system, much less is known concerning adverse effects of mercury on other organ systems, including the development of skeletal muscle. We exposed developing zebrafish embryos to a range of concentrations of mercuric chloride (100 to 400 µg/liter or ppb) and compared them to control embryos (0 µg/L mercuric chloride). Embryos were examined at 48 hours post fertilization (hpf) for morphometry and morphological deformities of skeletal muscle fibers in the trunk and tail. Embryos exposed to 400 ppb mercuric chloride showed decreased trunk and tail areas compared to control embryos. A dose-dependent reduction in muscle fiber length was observed, and exposure to all concentrations of mercuric chloride used in this study resulted in decreased muscle fiber immunohistochemical staining with anti-myosin antibodies. Irregular muscle fiber diameters, twisted muscle fibers, and degenerated muscle fibers were observed in sections of embryos stained with eosin at the higher exposure concentrations. Evidence presented in this study suggests that exposure to even low concentrations of mercuric chloride adversely affects skeletal muscle fiber development or muscle fiber integrity, or both.

La exposición al mercurio en el medio ambiente sigue siendo una preocupación mundial importante, especialmente para el desarrollo de embriones y fetos. Si bien un amplio esfuerzo de investigación se ha centrado en los efectos del mercurio en el sistema nervioso en desarrollo, se sabe mucho menos sobre los efectos adversos en otros sistemas orgánicos, incluido el desarrollo del músculo esquelético. Expusimos embriones de pez cebra en desarrollo a un rango de concentraciones de cloruro de mercurio (100 a 400 mg / l o ppb) y los comparamos con embriones de control (0 mg / L de cloruro de mercurio). Los embriones se examinaron a las 48 horas después de la fertilización (HPF) pararealizar la morfometría y verificar las deformidades morfológicas de las fibras del músculo esquelético en el tronco y la cola. Los embriones expuestos a 400 ppb de cloruro de mercurio mostraron una disminución de las áreas del tronco y la cola en comparación con los embriones de control. Se observó una reducción dependiente de la dosis en la longitud de la fibra muscular, y la exposición a todas las concentraciones de cloruro de mercurio utilizadas en este estudio, dio como resultado una tinción inmunohistoquímica de fibra muscular disminuida con anticuerpos anti-miosina. Se observaron diámetros irregulares de fibras musculares, fibras musculares retorcidas y fibras musculares degeneradas en secciones de embriones teñidos con eosina en las concentraciones de exposición más altas. La evidencia presentada en este estudio sugiere que la exposición incluso a bajas concentraciones de cloruro mercúrico afecta negativamente el desarrollo de la fibra del músculo esquelético o la integridad de la fibra muscular, o ambas.

Assessment of mercury contamination in Brycon falcatus (Characiformes: Bryconidae) and human health risk by consumption of this fish from the Teles Pires River, Southern Amazonia

Brycon falcatus is one of the most highly consumed species of fish within the region in the Teles Pires basin, and has great commercial importance in sport and professional artisanal fishing. The objective of this study was to analyze the presence and concentration of total mercury (THg) in the muscle, liver and gills of B. falcatus, and calculate the risk to human health of THg contamination from ingestion of the fish. THg concentrations were similar in the liver (0.076 mg kg-1) and muscle (0.052 mg kg-1), and higher than in the gills (0.009 mg kg-1). The levels of HgT present in B. falcatus tissues did not influence weight gain and nutritional status. Based on the condition factor, weight and length ratio and hepatosomatic index, it seems that the concentrations of THg did not influence the health and well-being of B. falcatus collected in the Teles Pires River basin. THg concentrations in the muscle of B. falcatus are below the limit recommended by the World Health Organization for people who consume until 250 g of fish per week. The risk of deleterious effects on human health may exist if there is a greater consumption of B. falcatus such as 340 g/day, that is the mean of fish consumption by indigenous and riverine.(AU)

Brycon falcatus é um dos peixes mais consumidos na região da bacia do rio Teles Pires, tendo grande importância comercial na pesca esportiva e profissional artesanal. O objetivo deste estudo foi analisar a presença e concentrações de mercúrio total (HgT) no músculo, fígado e brânquias do peixe B. falcatus. Foi calculado o risco para a saúde humana de contaminação por Hg pela ingestão deste pescado. As concentrações de HgT foram similares no fígado (0,076 mg.kg-1) e no músculo (0,052 mg.kg-1) e maiores do que nas brânquias (0,009 mg.kg-1). Os níveis de HgT presentes nos tecidos de B. falcatus não influenciaram no incremento de peso e estado nutricional. Com base no fator de condição, relação peso e comprimento e índice hepatossomático, aparentemente as concentrações de THg não influenciaram a saúde e o bem-estar de B. falcatus coletados na bacia do rio Teles Pires. As concentrações de THg no músculo de B. falcatus estão abaixo do limite recomendado pela Organização Mundial de Saúde para pessoas que consomem até 250 g de peixe por semana. O risco de efeitos deletérios para a saúde humana pode existir se houver um maior consumo de B. falcatus, como 340 g/dia, que é a média do consumo de peixe por indígenas e ribeirinhos.(AU)

Evaluación de los Niveles de Mercurio en Productos Pesqueros en Costa Rica, Durante 2003-2013, como insumo para recomendar una ingesta semanal tolerable / Evaluation of Mercury Levels in Fishery Products in Costa Rica, During 2003-2013, as an Input to recommend a tolerable weekly intake

ResumenLos peces y mariscos pueden acumular mercurio en sus tejidos. En este trabajo se establecen recomendaciones de consumo de productos pesqueros para los residentes de Costa Rica, a partir de la evaluación de los niveles de mercurio en pescados y mariscos analizados durante los años 2003-2013.Objetivo: Evaluar los niveles de mercurio (en mg/kg) en muestras de productos pesqueros, analizadas por el Laboratorio Nacional de Servicios Veterinarios (LANASEVE) del Servicio Nacional de Salud Animal (SENASA) de Costa Rica, durante el período 2003-2013, para sugerir un valor de Ingesta Semanal Tolerable Recomendada (ISTR) de pescados y mariscos.Materiales y métodos: Los ensayos de mercurio se realizaron, bajo un esquema de análisis de riesgo determinado por el Programa Nacional de Residuos del SENASA, en pescados y mariscos. Las muestras de músculo fueron recolectadas por personal del SENASA y enviadas al LANASEVE para evaluar los niveles de Hg. Las concentraciones de mercurio fueron luego comparadas con los dos valores límite establecidos por la normativa nacional e internacional para productos pesqueros: 1 mg Hg/kg para pescados depredadores y 0,5 mg Hg/kg para otros productos pesqueros.Resultados: Se encontró que aproximadamente el 85 % de las muestras de pescados depredadores cumplió con el valor límite de 1 mg Hg/kg. Por su parte, el 93 % de los otros productos pesqueros evaluados, mostraron niveles de mercurio por debajo de 0,5 mg Hg/kg.Conclusión: Para mujeres embarazadas se establecieron valores de ISTR de 171 g de pescados depredadores o 889 g de otros productos pesqueros, en tanto para niños los ISTR recomendados fueron 100 g de pescados depredadores y 519 g de otros productos pesqueros.

AbstractFish and seafood can accumulate mercury in their tissues. This work establishes fishery products intake recommendations for the residents of Costa Rica, based upon the evaluation of mercury levels on fish and seafood analyzed during years 2003-2013.Objective: To evaluate mercury levels (in mg/kg) in fishery samples, as analyzed by the National Veterinary Services Laboratory (LANASEVE) of the National Animal Health Service (SENASA) of Costa Rica, during the 2003-2013 period, to suggest a Tolerable Weekly Intake Recommendation (TWIR) for fish and seafood.Methods: Mercury assays were performed, under a risk-analysis scheme determined by the National Residue Program of SENASA, in fish and seafood. Muscle samples were collected by SENASA staff and sent to LANASEVE for evaluation of Hg contents. Mercury concentrations were then compared to two limit values established by national and international regulations for seafood: 1 mg Hg/kg for predatory fish, and 0,5 mg Hg/kg for other fishery products.Results: It was found that, approximately, 85 % of predatory fish samples complied with the 1 mg Hg/kg limit value. Meanwhile, 93 % of the other fishery products analyzed, showed mercury levels below 0,5 mg/kg.Conclusion: For pregnant women TWIR values were established at 171 g for predatory fish and 889 g for other fishery products, while for children the TWIR values were 100 g for predatory fish and 519 g for other fishery products.

Analysis for the presence of determinants involved in the transport of mercury across bacterial membrane from polluted water bodies of India

Abstract Mercury, which is ubiquitous and recalcitrant to biodegradation processes, threatens human health by escaping to the environment via various natural and anthropogenic activities. Non-biodegradability of mercury pollutants has necessitated the development and implementation of economic alternatives with promising potential to remove metals from the environment. Enhancement of microbial based remediation strategies through genetic engineering approaches provides one such alternative with a promising future. In this study, bacterial isolates inhabiting polluted sites were screened for tolerance to varying concentrations of mercuric chloride. Following identification, several Pseudomonas and Klebsiella species were found to exhibit the highest tolerance to both organic and inorganic mercury. Screened bacterial isolates were examined for their genetic make-up in terms of the presence of genes (merP and merT) involved in the transport of mercury across the membrane either alone or in combination to deal with the toxic mercury. Gene sequence analysis revealed that the merP gene showed 86–99% homology, while the merT gene showed >98% homology with previously reported sequences. By exploring the genes involved in imparting metal resistance to bacteria, this study will serve to highlight the credentials that are particularly advantageous for their practical application to remediation of mercury from the environment.

Intoxicación por mercurio elemental por inyección intramuscular: presentación de caso y revisión de literatura / Poisoning with elemental mercury by intramuscular injection. Case report and review of literature

Se han reportado en la literatura pocos casos de intoxicación por mercurio por administración en tejidos blandos. No se cuenta con suficiente evidencia acerca del manejo con terapia quelante en este tipo de intoxicación. Se reporta el caso de una mujer de 34 años con antecedente psiquiátrico la cual se administró mercurio intramuscular en fosa cubital izquierda con fines autolíticos. Acudió al servicio de urgencias 24 horas posteriores a su administración, el motivo principal fue el dolor intenso en la zona y la presencia de edema, sin efectos sistémicos. La radiografía mostró depósitos metálicos en 1/3 de brazo, localizados en músculo, y que migraron a través de la fascia hacia 2/3 del antebrazo. La placa de tórax no mostró alteraciones. Fue intervenida quirúrgicamente en 3 ocasiones extrayendo mínimas cantidades de mercurio. La paciente fue manejada con antibióticos por presencia de celulitis. Un mes después presentó temblor mercurial, razón por la cual se tomaron muestras de sangre y orina para la determinación de mercurio, el cual resulto elevado en ambas muestras, por lo que se le administró terapia quelante con D-penicilamina.

There are just a few cases of mercury toxicity after administration in soft tissue, reported in the literature. There is insufficient evidence about the management with chelation therapy in this type of poisoning. We report the case of a 34 year-old woman with a psychiatric history who administered herself a mercury injection into de muscle in the left cubital fossa, referred as a suicide attempt. She came to the emergency department 24 hours after administration; the main reason was the intense pain in the area and the presence of edema, with no systemic effects. Radiography showed metallic deposits in 1/3 arm, located in muscle, which moved through the fascia to 2/3 of the forearm. Chest radiography was normal. She underwent surgery trhee times extracting trace amounts of mercury. The patient was managed with antibiotics by the presence of cellulite. One month later she had tremor mercuralis, so a blood and urine samples were sent to the laboratory in order to determinate mercury levels, which resulted high in both fluids, therefore chelation therapy with D-penicillamine was administered.

Níveis de metais no solo e na água da microbacia do distrito Industrial do Pequiá, município de Açailândia, MA / Levels of metals in soil and water catchment Industrial District Pequiá, municipality of Açailândia, MA

Este estudo determinou a concentração de vários metais no solo e na água da microbacia do distrito industrial do Pequiá, Açailândia-MA, e investigou a variação das concentrações dos metais no solo em função da distância às indústrias. Os metais investigados os metais foram Arsênio (As), Cádmio (Cd), Manganês (Mn), Mercúrio (Hg), Chumbo (Pb) e Níquel (Ni), que podem acarretar diversos agravos na saúde em virtude da sua toxicidade em diferentes alvos biológicos. O distrito industrial do Pequiá é caracterizado por indústrias siderúrgicas e rodovias com intenso tráfego de veículos a combustão, o que desperta a necessidade de se conhecer as concentrações ambientais desses metais. Metodologia: Foram coletadas 44 amostras de solo do entorno das indústrias nos período seco e chuvoso, respectivamente, e água de três pontos do córrego Pequiá no período chuvoso. A determinação da concentração de metais em solo foi realizada por Espectrometria de Emissão Atômica por Plasma Acoplado Indutivamente (ICP-OES), e em água por meio de Espectrometria de Massa com Plasma Acoplado Indutivamente (ICP-MS). (...) O único metal detectado em todas as amostras no período seco foi o Hg. A análise de correlação entre as concentrações no solo em cada período revelou correlação positiva estatisticamente significativa entre Pb e Mn no período chuvoso e correlação negativa com significância limítrofe entre Mn e Hg. Em relação ao gradiente de concentração, se observou diminuição apenas da concentração de Pb ao longo da linha reta entre as indústrias e o bairro Pequiá. A diminuição da concentração de Pb com a distância foi estatisticamente significativa, tanto no período chuvoso quanto no seco. Conclusão: Os metais Mn e Pb foram os mais frequentemente encontrados e com as concentrações mais elevadas tanto no solo quanto na água, muito provavelmente devido ao processo de fabricação do ferro gusa e ao intenso tráfego de veículos...

This study determined the concentration of heavy metals in soil and surface water in the industrial district of Pequiá, Açailândia-MA, as well as investigated the variation in concentration of metals in soil with the distance to the industries. Metals investigated were Arsenic (As), Cadmium (Cd), Manganese (Mn), Mercury (Hg), Lead (Pb) and Niquel (Ni), which may cause several health effects. The Pequiá industrial district is composed by several steel plants and roads with heavy vehicle traffic. Methods: Soil samples were collected from 44 points around the industrial district in the dry and rainy season, respectively, and water samples were collected at three points of the Pequiá stream during the rainy season. Concentrations of metals in soil were determined by inductively coupled plasma optical emission spectrometry (ICP-OES), and by inductively coupled plasma mass spectrometry (ICP-MS). (...) Hg was the only metal detected in all soil samples in the dry season. Correlation analysis between concentrations of metals in soil showed a statistically significant positive correlation between Pb e Mn in the rainy season. Pb was the only metal showing a reduction in concentration across the straight line between the industries and Pequiá neighborhood. Reduction in Pb concentration with increasing distance was statistically significant in both seasons. Conclusions: Mn e Pb were the metals most frequently found and those presenting the highest concentrations in soil and water, suggesting that the main sources of these metals in the study area may be iron manufacturing process and motor vehicle traffic...

A study of sister chromatid exchange in patients with dental amalgam restorations.

Study Background: Dental amalgam is still widely used as a restorative material in developing countries due to its low cost and ease of manipulation. The health risks associated with the components of this restorative material has always been a matter of concern. Our study was designed to address this question regarding dental amalgam. Objective: To study sister chromatid exchange (SCE) as an indicator of systemic genotoxicity, due to the exposure from the components of amalgam restorations during its placement and chronic use. Materials and Methods: Systemic genotoxicity in subjects exposed to amalgam during its placement (Group II; n = 5) and subjects with chronic exposure to amalgam (Group III; n = 5) were compared with controls (Group I; n = 5) by SCE assay in cultured peripheral blood lymphocytes. Result: Subjects exposed to amalgam during its placement and subjects having chronic exposure to amalgam showed an increase in the frequency of SCE, but the change was not statistically significant (P = 0.84, P = 0.123 respectively). Conclusion: Systemic genotoxicity was not observed due to the components of amalgam restorations released during its placement and chronic use. The findings of this study can be considered as preliminary information on the systemic toxicity due to the components of amalgam restorations.

Nefropatía membranosa secundaria a exposición laboral con mercurio metálico

Las nefropatías tóxicas secundarias a la exposición ocupacional a metales han sido ampliamente estudiadas. La nefropatía membranosa por mercurio es poco frecuente.La intoxicación ocupacional con mercurio sí es frecuente, siendo las principales formas de presentación las manifestaciones clínicas neurológicas. La afectación renal secundaria a la exposición crónica a mercurio metálico puede desarrollar enfermedad glomerular por depósito de inmunocomplejos. La glomerulopatía membranosa y a cambios mínimos son las más frecuentemente comunicadas.Se presenta el caso de un paciente con exposición ocupacional a mercurio metálico, con síndrome nefrótico y biopsia renal con glomerulopatía membranosa que presentó respuesta favorable luego del tratamiento quelante e inmunosupresor.

Toxic nephrophaties secondary to occupational exposure to metals have been widely studied, including membranous nephropathy by mercury, which is rare. Occupational poisoning by mercury is frequent, neurological symptoms are the main form of clinical presentation. Secondary renal involvement in chronic exposure to metallic mercury can cause glomerular disease by deposit of immune-complexes. Membranous glomerulopathy and minimal change disease are the most frequently reported forms. Here we describe the case of a patient with occupational exposure to metallic mercury, where nephrotic syndrome due to membranous glomerulonephritis responded favorably to both chelation and immunosuppressive therapy.

Mercurio en pescados y su importancia en la salud / Mercury in fish and its importance in health

The contamination of fish with methylmercury (MeHg) could hamper the health promoting properties of fish. Currently, there is strong evidence about the health benefits of seafood consumption. When consumed by the mother before and during pregnancy it improves neurodevelopment of infants and toddlers. Thereafter it reduces the risk of cardiovascular and other chronic diseases. The benefits of fish are mainly due to its content of omega-3 long chain polyunsaturated fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Other constituents, such as high biological value proteins, fat-soluble vitamins, minerals and trace elements contribute to the benefits. On the other hand, there is also convincing evidence about the adverse effects of MeHg on neurodevelopment both during gestation and in early childhood. We herein review the effects of mercury on health. Based on international evidence and new data on the mercury content in Chilean fish, we also propose a recommendation for fish consumption for our population.

O uso de Timerosal em vacinas, as implicações para o Programa Nacional de Imunizações Brasileiro e a nova Convenção de Minamata sobre o mercúrio / The use of Thimerosal in vaccines, the implications for the Brazilian National Immunization Program and the new Minamata Convention on Mercury

Este trabalho teve por objetivo contextualizar a discussão em relação ao uso de Timerosal em Vacinas e suas implicações para a saúde das pessoas, tendo em vista a discussão no Conselho de Ministros do Programa das Nações Unidas para o Meio Ambiente (PNUMA), onde se montou um Grupo de Trabalho para o estabelecimento de uma Convenção com o objetivo de banir o metal mercúrio e seus subprodutos do uso cotidiano, como forma de reduzir a exposição antrópica e a toxidade desse elemento em todas as cadeias humanas de produção. Nesse processo de discussão, com a participação dos Países Partes do PNUMA, da sociedade civil internacional,da academia, de outros Órgãos das Nações Unidas - a exemplo da Organização Mundial da Saúde (OMS) - e da indústria, foi concretizada a Convenção de Minamata para o Mercúrio. Esse trabalho reflete as participações do pesquisador nos encontros entre os Países e inúmeras outras reuniões entre os grupos de contato, onde participou como delegado do Ministério da Saúde.Trabalhos de pesquisa, onde o pesquisador é ator participante da discussão e de seus ensinamentos, permitem uma visão do contexto da criação da normatização que tem utilidade no contexto de Políticas Públicas para o Setor Saúde.

This study aimed to contextualize the discussion regarding the use of Thimerosal in vaccines and their implications for human health, in view of the discussion in the Council of Ministers of the United Nations Environment Programme (UNEP), where a Working Group was set for the establishment of a Convention with the purpose of banning mercury and by products of every day use, as a way to reduce anthropogenic exposure and toxicity of this element in all human production chains. The Minamata Convention on Mercury is the result of a process of discussion, with the participation of UNEP Country Parties, international civil society, academia, other United Nations bodies - such as the World Health Organization (WHO) - and industry. This work reflects the participation of the researcher, as delegate of the Ministry of Health, to the meetings of the Working Groups, and all other ones held by contact groups, and its learning, which made possible to be inside the context of the creation of norms, which is useful to a better understanding of Public Policies for the Health Sector.