Metal Exposure in Arica, Chile: Examining Toxic Elements / Análisis de exposición a metales en Arica, Chile: niveles de elementos tóxicos

BACKGROUND: Bioaccumulation of toxic metals in the population is associated with adverse health effects. Although some elements are essential for humans, high levels of exposure can be dangerous. OBJECTIVE: To describe the levels of Inorganic Arsenic (AsIn), Cadmium (Cd), Chromium (Cr), and Mercury (Hg) in urine, and Lead (Pb) in blood in the population of Arica, Chile. METHODOLOGY: Descriptive study. Beneficiaries of the Health Surveillance Program of Law 20.590 in sites of higher risk of exposure in the commune of Arica were considered eligible. The results of biological samples to measure their concentrations of AsIn, Cd, Cr, Hg in urine, and Pb in blood between August 2016 and May 2021 are described. RESULTS: 9520 samples from a population with a mean age of 40.5 years were studied. 4.21% of the adult population and 6.57% of the children had AsIn values above 35 μg/L, while at least 95 % of the total samples had levels below 33 μg/L. At least 90 % of the samples had Cd levels below 1.1 μg/L, and 8.44 % had Cd levels above 2 μg/L, higher in males (11.67%). There were no values above the reference in children. 99.77% and 99.33% had Cr and Pb values below the reference limit, respectively (using the lowest reference range established by Chile Ministry of Health (MINSAL) < 5 μg/L). Children did not present risk values for Cr, and 0.16% presented Pb concentrations between 5-10 μg/dL. All samples presented Hg concentrations below risk levels (< 10 μg/L). CONCLUSIONS: The results of this study suggest that a small percentage of the samples analyzed in the beneficiary population of Arica register metal concentration levels above national reference levels established by MINSAL, mainly AsIn, Cd, and Pb. It is essential to continue biomonitoring to reduce and prevent exposure to these metals, which can have harmful effects on human health.

ANTECEDENTES: La bioacumulación de metales en la población está asociada a efectos adversos y pueden ser peligrosos. OBJETIVO: Describir los niveles de Arsénico Inorgánico (AsIn), Cadmio (Cd), Cromo (Cr), Mercurio (Hg) y Plomo (Pb) en la población de Arica, Chile. MATERIALES Y MÉTODOS: Estudio descriptivo. Se incluyeron todas las personas beneficiarias del Programa de Vigilancia de Salud de la Ley 20.590 en sitios de riesgo de mayor exposición en la comuna de Arica entre agosto 2016 y mayo 2021. RESULTADOS: Se estudiaron 9.520 muestras provenientes de una población con una edad media de 40.5 años. 4.21% de la población adulta y el 6.57% de los niños presentaron valores de AsIn superiores a 35 μg/L y al menos el 95% de las muestras totales tenía niveles inferiores a 33 μg/L. Más del 90 % de las muestras tuvieron niveles de Cd menores a 1.1 μg/L y un 8.44% registró niveles de Cd superiores 2 μg/L. El 99.77% y 99.33% exhibieron valores normales de Cr y Pb, respectivamente. Todas las muestras presentaron concentraciones de Hg por debajo de los niveles de riesgo (< 10 μg/L). CONCLUSIONES: Los resultados sugieren que un porcentaje pequeño de la población de Arica registra niveles de concentración de metales por sobre niveles de referencia nacional establecidos por el Ministerio de Salud de Chile, principalmente de AsIn, Cd y Pb. Es importante continuar con la vigilancia para reducir y prevenir la exposición a estos metales, que pueden generar efectos nocivos en la salud humana.

Avaliação de risco à saúde humana associada a exposição inalatória de arsênio, níquel e chumbo no MP10 de fonte veicular, na cidade de São Paulo, SP / Assessment of human health risks associated with airborne arsenic, nickel and lead exposure in PM10 from vehicular sources in Sao Paulo city

Introdução. O material particulado (MP) emitido pela queima de combustíveis fósseis de origem veicular é a principal fonte de exposição ambiental à elementos potencialmente tóxicos (EPTs) presentes no ar atmosférico dos centros urbanos, entre eles arsênio, níquel e chumbo. Objetivos. Este estudo avaliou os riscos à saúde humana de efeitos não carcinogênicos e efeitos carcinogênicos associados a exposição inalatória de arsênio, níquel e chumbo no MP10 de origem veicular, coletado em uma das estações de monitoramento da qualidade do ar, na cidade de São Paulo, ao longo dos anos 2002, 2006, 2009 e 2012. Métodos. Os dados de concentração dos EPTs foram obtidos pela Companhia Ambiental do Estado de São Paulo (CETESB) e estão disponíveis no website da agência. As amostras semanais foram coletadas em todas as estações do ano, durante 2002, 2006, 2009 e 2012 na estação de monitoramento Cerqueira César, localizada próximo a uma via de intenso tráfego veicular. A análise estatística foi realizada utilizando o Software R (versão 4.0.5) e RStudio (versão 1.2). O software ProUCL foi usado para estimar os valores UCL95%. A avaliação de risco à saúde humana foi realizada de acordo com os métodos da United States Environmental Protection Agency (USEPA). Resultados. As concentrações de arsênio e chumbo no ar apresentaram médias mais elevadas durante o inverno do que nas outras estações (p <0,05). O chumbo apresentou o maior risco de efeitos não carcinogênicos (HQ> 1,0). Arsênio e níquel apresentaram o maior risco de efeitos carcinogênicos, inclusive acima de 1E-06. O risco para ambos os efeitos foi maior no inverno. Conclusão. Esses achados destacam a importância da poluição do ar como fator de risco para a saúde da população, principalmente em centros urbanos com intenso tráfego veicular. Ações para reduzir a exposição à poluição do ar ambiente devem ser priorizadas nas agendas de políticas ambientais e de saúde.

Background. Particulate matter (PM) emitted from the burning of fuels by vehicles is the main source of environmental exposure to potentially toxic elements (PTEs) present in atmospheric air in urban centers, between them arsenic, nickel and lead. Objective. This study evaluated the risk to human health from non-carcinogenic effects and carcinogenic effects associated with airborne arsenic, nickel and lead in PM10 exposure of the vehicular source collected at one of the air quality monitoring stations in the city of Sao Paulo over the years 2002, 2006, 2009 and 2012. Methods. The concentration data of the PTEs were obtained by the Sao Paulo State Environmental Protection Agency (CETESB) and are available on the agency's website. The statistical analysis was performed using the Software R (version 4.0.5) and RStudio (version 1.2). ProUCL software was used to estimate UCL95% values. The risk assessment for human health was carried out according to the methods of the United States Environmental Protection Agency (USEPA). Results. Airborne arsenic and lead concentrations showed higher means during the winter than in other seasons (p<0.05). Lead had the greatest risk of non-carcinogenic effects (HQ>1.0). Arsenic and nickel had the highest risk of carcinogenic effects, including above 1E-06. The risk for both effects was greatest in winter. Conclusion. These findings highlight the importance of air pollution as a risk factor for population health, especially in urban centers with high vehicular traffic. Actions to reduce air pollution exposure should be prioritized in environmental and health policies agendas.

Characterization of metal(loid)s and antibiotic resistance in bacteria of human gut microbiota from chronic kidney disease subjects

BACKGROUND: Human Gut Microbiota (HGM) is composed of more than one thousand species, playing an important role in the health status of individuals. Dysbiosis (an HGM imbalance) is augmented as chronic kidney disease (CKD) progresses, as loss of kidney function accelerates. Increased antibiotic use in CKD subjects and consumption of nephrotoxic heavy metals and metalloids such as lead, cadmium, arsenic, and mercury in tap water increases the dysbiosis state. Studies in people with stage 3 CKD are complex to carry out, mainly because patients are self-reliant who rarely consult a specialist. The current work focused on this type of patient. RESULTS: Lead and arsenic-resistant bacteria were obtained from self-reliant (that stands on its own) stage 3 CKD subjects. Pathogen-related Firmicutes and Proteobacteria genus bacteria were observed. Resistance and potentiation of antibiotic effects in the presence of metal(loid)s in vitro were found. Furthermore, the presence of the following genes markers for antibiotic and metal(loid) resistance were identified by qPCR: oxa10, qnrB1, mphB, ermB, mefE1, arr2, sulll, tetA, floR, strB, dhfr1, acrB, cadA2k, cadA3k, arsC, pbrA. We observed a decrease in the number of metal resistance markers. CONCLUSIONS: The presence of cadA and arsC genetic markers of antibiotics and metal(loid)s resistance were detected in samples from stage 3 CKD subjects. Lower gene amplification in advanced stages of CKD were also observed, possibly associated with a decrease in resident HGM during kidney disease progression.

Prevalencia de hipertensión arterial y factores de riesgo cardiovascular en una población rural expuesta al arsénico en Argentina / Prevalence of arterial hypertension and cardiovascular risk factors in a rural population exposed to arsenic in Argentina

RESUMEN Objetivos. Determinar la prevalencia de hipertensión arterial y factores de riesgo cardiovascular (FRC) en una población rural expuesta al arsénico (As) en el agua de consumo en la provincia de Tucumán, Argentina. Materiales y métodos. Participaron 352 habitantes adultos. Se midió el consumo de arsénico en agua de bebida y se evaluó la presión arterial, el tabaquismo, el consumo de alcohol de riesgo y perjudicial, la ingesta de sal, la actividad física, el índice de masa corporal, la glucemia y la dislipidemia. El riesgo cardiovascular fue calculado usando el score de Framingham. Resultados. Se dividió la población en Grupo Expuesto (GE) n=90 y Grupo No Expuesto (GNE) n=262. La prevalencia de hipertensión fue 48,9 y 51,1%; tabaquismo 31,1 y 39,7%; consumo de alcohol de riesgo 22,2 y 17,9%; perjudicial 36,6 y 36,6%; ingesta de sal 100 y 100%; actividad física 16,7 y 18,7%; sobrepeso 43,3 y 43,9%; obesidad 25,5 y 25,6%; diabetes 24,4 y 32,8%; y dislipidemia 58,9 y 66,4%. El score de riesgo bajo, moderado o alto fue 50; 21,1; y 28,9% para GE, y 54,6; 19,1 y 26,3% para GNE, respectivamente. Conclusiones. La exposición al As no afecta la prevalencia de FRC. Se identifica una población rural en situación de vulnerabilidad con elevados FRC. La Encuesta Nacional de Factores de Riesgo no refleja lo que ocurre en zonas rurales. La escala de Framingham concuerda con los FRC encontrados. Se requiere la implementación de políticas de promoción de salud que permita mejorar el pronóstico de sufrir eventos cardiovasculares a corto y mediano plazo.

ABSTRACT Objective. To determine the prevalence of arterial hypertension and cardiovascular risk factors (CRF) in a rural population exposed to arsenic (As) in drinking water in the province of Tucumán, Argentina. Materials and methods. A total of 352 adult inhabitants participated. Consumption of arsenic in drinking water was measured. Blood pressure, smoking, risk and harmful alcohol consumption, salt intake, physical activity, body mass index, glycemia and dyslipidemia were evaluated. Cardiovascular risk was calculated using the Framingham score. Results. The population was divided into Exposed Group (EG) n=90 and Non-Exposed Group (NEG) n=262. The prevalence of hypertension was 48.9 and 51.1% in each group, respectively; for smoking it was 31.1 and 39.7%; for risky alcohol consumption, 22.2 and 17.9%; for harmful alcohol consumption, 36.6 and 36.6%; for salt intake, 100 and 100%; for physical activity, 16.7 and 18.7%; for being overweight, 43.3 and 43.9%; for obesity, 25.5 and 25.6%; for diabetes, 24.4 and 32.8%; and for dyslipidemia, 58.9 and 66.4%. The scores for low, moderate, or high-risk were 50; 21.1; and 28.9% in the EG, and 54.6; 19.1 and 26.3% in the NEG, respectively. Conclusions. Exposure to As does not affect the prevalence of CRFs. We identified a rural population in a vulnerable condition with high CRFs. The National Risk Factor Survey does not reflect what happens in rural areas. The Framingham scale is consistent with the found CRFs. The implementation of health promotion policies is required to improve the prognosis of suffering cardiovascular events in the short and medium term.

High arsenic tolerance in Brevundimonas aurantiaca PFAB1 from an arsenic-rich Indian hot spring

BACKGROUND Arsenic contamination in the ground water of rural India is a recurrent problem and decon tamination is mostly based on the chemical or physical treatments until now. Microbial bioremediation is eco-friendly, cheap, time-efficient and does not produce any toxic by-products. RESULT In the present study, a high arsenic tolerant bacteria Brevundimonas aurantiaca PFAB1 was iso lated from Panifala hot spring located in West Bengal, India. Previously Panifala was also reported to be an arsenic-rich hot spring. B. aurantiaca PFAB1 exhibited both positive arsenic reductase and arsenite oxidase activity. It was tolerant to arsenite up to 90 mM and arsenate up to 310 mM. Electron microscopy has proved significant changes in cellular micromorphology and stalk appearance under the presence of arsenic in growth medium. Bioaccumulation of arsenic in As (III) treated cells were 0.01% of the total cell weight, while 0.43% in case of As (V) treatment. CONCLUSIONS All experimental lines of evidence prove the uptake/accumulation of arsenic within the bac terial cell. All these features will help in the exploitation of B. aurantiaca PFAB1 as a potent biological weapon to fight arsenic toxicity in the near future

Exposição a metais em população adulta residente em áreas industriais: revisão sistemática da literatura / Exposure to metals in the adult population living in industrial areas: a systematic review of the literature

Resumo Este artigo objetivou revisar os estudos de biomonitoramento humano (BMH) que avaliaram a exposição a chumbo (Pb), cádmio (Cd), mercúrio (Hg), níquel (Ni), arsênio (As) e manganês (Mn) em adultos residentes próximo a áreas industriais. Realizou-se uma revisão sistemática, sem limite de data inicial até dezembro de 2017, utilizando a base de dados da MEDLINE e a BVS. Foram incluídos estudos originais em inglês, português ou espanhol, com uso de sangue e/ou urina como biomarcador. Os artigos foram avaliados pelos critérios metodológicos, incluindo-se estudos com grupo de comparação e/ou amostragem probabilística. Dos 28 estudos incluídos, 54% foram realizados na Europa, 36% na Ásia, 7% na América do Norte e 4% na África. Fundições, metalúrgicas e siderúrgicas foram as indústrias mais estudadas. Urina e sangue foram usados em 82% e 50% dos estudos, respectivamente. Os elementos mais investigados foram Cd, Pb e As. Embora com metodologias heterogêneas, em geral, os estudos observaram maiores concentrações de metais em expostos, especialmente As e Hg, do que nos grupos de comparação. Esta revisão evidencia a necessidade de estudos de BMH com maior rigor metodológico, reforçando a importância da vigilância em saúde de populações expostas a metais tóxicos, sobretudo nos países em desenvolvimento.

Abstract This study aimed to review studies of human biomonitoring (HBM) that evaluated exposure to lead (Pb), cadmium (Cd), mercury (Hg), nickel (Ni), arsenic (As) and manganese (Mn) in adults living close to industrial areas. A systematic review of studies was selected, without initial date limit through to December 2017, from the MEDLINE and BVS databases. Original studies in English, Portuguese or Spanish conducted among the adult population using blood and/or urine as biomarkers were included. The articles were evaluated according to methodological criteria, including studies with comparison groups and/or probabilistic sampling. Of the 28 studies selected, 54% were conducted in Europe, 36% in Asia, 7% in North America and 4% in Africa. Foundries, metal works and steel mills were the most frequently studied. Urine and blood were used in 82% and 50% of studies, respectively. The elements most investigated were Cd, Pb and As. Despite using heterogeneous methodologies, the results revealed higher metal concentrations, especially from As and Hg in general, than in the comparison group. This review highlights the need for more rigorous methodological studies of HBM, stressing the importance of public health vigilance among populations exposed to toxic metals, especially in developing countries.

Arsenotoxicidad aguda experimental en ratones Balb/c: marcadores orgánicos y compromiso esplénico / Experimental acute arsenic toxicity in Balb/c mice: organic markers and splenic involvement

Resumen | Introducción. El arsénico es un tóxico ambiental ampliamente diseminado en todo el mundo. En hombres y animales, diversos órganos y tejidos son blancos de sus efectos deletéreos, entre ellos, el los del sistema inmunológico. Objetivo. Determinar la intoxicación aguda por arsénico en tejidos y células diana de ratones Balb/c in vivo. Materiales y métodos. Se aplicó una inyección intraperitoneal de 9,5 o 19 mg/kg de arsenito de sodio (NaAsO2) o un volumen equivalente de solución fisiológica como control, en ratones Balb/c con 3 por cada grupo experimental. Tras media hora, los animales fueron sacrificados y se extrajeron bazos, timos, hígados, riñones y sangre. En cada muestra, se determinó la concentración de arsénico, polifenoles y hierro, y también, se evaluaron marcadores oxidativos, como peróxidos, productos avanzados de oxidación proteica y grupos sulfhidrilos libres. En los esplenocitos obtenidos del bazo, se determinaron la viabilidad celular y el potencial mitocondrial. Resultados. La dosis aguda inyectada de NaAsO2 redujo la función mitocondrial de los esplenocitos, lo que derivó en muerte celular. La presencia confirmada de arsénico en las muestras de bazo y la citotoxicidad resultante, produjeron disminución de los polifenoles y de los grupos sulfhidrilos libres, y alteraron el contenido y la distribución del hierro, pero no se aumentó la producción de peróxidos. Conclusión. Estos hallazgos aportan evidencia científica sobre los cambios en biomarcadores involucrados en la inmunotoxicidad del arsénico y ofrecen, además, una metodología para ensayar potenciales tratamientos frente a la acción deletérea de este compuesto en el sistema inmunológico.

Abstract | Introduction: Arsenic is an environmental toxic present worldwide. In men and animals, various organs and tissues are targets of its deleterious effects including those of the immune system. Objective: To determine acute arsenic toxicity in tissues and target cells of Balb/c mice using an in vivo methodology. Materials and methods: We injected Balb/c mice intraperitoneally with 9.5 or 19 mg/ kg of sodium arsenite (NaAsO2), or an equivalent volume of physiological solution as a control (with 3 per experimental group). After 30 minutes, the animals were sacrificed to obtain spleen, thymus, liver, kidneys, and blood. We determined arsenic, polyphenols, and iron concentrations in each sample and we evaluated the oxidative markers (peroxides, advanced products of protein oxidation, and free sulfhydryl groups). In splenocytes from the spleen, cell viability and mitochondrial potential were also determined. Results: The exposure to an acute dose of NaAsO2 reduced the mitochondrial function of splenocytes, which resulted in cell death. Simultaneously, the confirmed presence of arsenic in spleen samples and the resulting cytotoxicity occurred with a decrease in polyphenols, free sulfhydryl groups, and an alteration in the content and distribution of iron, but did not increase the production of peroxides. Conclusion: These findings provide scientific evidence about changes occurring in biomarkers involved in the immunotoxicity of arsenic and offer a methodology for testing possible treatments against the deleterious action of this compound on the immune system.

Elaboration of reference material for cadmium and arsenic in hydrobiological products, for the purpose of being used in a laboratory intercomparation program / Elaboración de un material de referencia para cadmio y arsénico en productos hidrobiológicos, para propósito de ser utilizado en un programa de intercomparación de laboratorios

Reference materials (RM) are tools used in the comparability and traceability of measurements. They are widely used by laboratories for method validation and quality control of assay. Chile must evaluate theperformance of laboratories that analyzing metals in fishery products, despite RM have high prices and are scarce. For that reason, a RM in a hydrobiological product was developed. Reference values for arsenic and cadmium elements for a fishmeal were assigned. The measurement methods for characterization of the material were Inductively Coupled Plasma Mass Spectrometry, Atomic Absorption Spectrometry and Neutron Activation Analysis. Reference values with their expanded uncertainty (U) were established for arsenic 2.64 ± 0.42 mg/kg (U; k = 2) and for cadmium 0.86 ± 0.16 mg/kg (U; k = 2). Homogeneity and stability of the RM allowed its use in a proficiency test for eleven food control laboratories. Results for median were 2.114 mg/kg for arsenic, and 0.863 mg/kg for cadmium. The performance values of the participants were evaluated with a z score obtaining 60% satisfaction for arsenic and 73% for cadmium.The material demonstrated to be suitable for use in interlaboratory proficiency assay. (AU)

Materiales de referencia (MR) son herramientas utilizadas en la comparabilidad y trazabilidad entre mediciones. Laboratorios los utilizan ampliamente en validación de métodos y control de calidad. Chile debe evaluar el desempeño de los laboratorios que analizan metales en productos pesqueros, a pesar de los altos precios y escasez del MR. Por esa razón, se desarrolló un MR en producto hidrobiológico. Se asignaron valores de referencia para arsénico y cadmio en harina de pescado. Los métodos de medición para la caracterización del material fueron Espectrometría de Masas de Plasma Acoplado Inductivamente, Espectrometría de Absorción Atómica y Análisis de Activación de Neutrones. Se establecieron valores de referencia con su incertidumbre (U) para arsénico 2.64 ± 0.42 mg/kg (U; k = 2) y para cadmio 0.86 ± 0.16 mg/kg (U; k = 2). La homogeneidad y estabilidad del MR permitieron su uso en una prueba de aptitud para once laboratorios de control de alimentos. Las medianas fueron 2,114 mg/kg para arsénico y 0,863 mg/kg para cadmio. Se evaluaron los rendimientos de los participantes con un estadístico de puntaje z satisfactorio del 60% para el arsénico y 73% para el cadmio. El material demostró ser adecuado para uso en ensayo de aptitud de intercomparación. (AU)

Effects of Curcumin on Sodium Arsenite Induced Neoplastic Cell Transformation in Balb/c 3T3 Cells

HIGHLIGHTS Sodium arsenite can cause neoplastic transformation in cells. Curcumin reduced cell viability and increased LDH activity in transformed Balb/c 3T3 cells. Curcumin caused DNA damage in transformed Balb/c 3T3 cells. Curcumin may play a protective role in sodium arsenite-induced toxicity.

Abstract Arsenic is a toxic substance that spreads widely around the environment and accumulates as metalloid in the earth's crust. Arsenic and its derivatives are found in drinking water, nutrients, soil, and air. Exposure to arsenic is associated with lung, blood, skin cancer and various lesions. Curcumin is a polyphenolic compound derived from Curcuma longa (turmeric) rhizome and is one of the main curcuminoids. Curcumin is known to be antioxidant, antibacterial, anti-inflammatory, analgesic effects. This study aimed to investigate the potential of sodium arsenite to transform embryonic fibroblast cells and to evaluate the cytotoxic and genotoxic effects of curcumin in neoplastic transformed cells. Neoplastic cells transformation was induced by sodium arsenite in Balb/c 3T3 cells at the end of 32 days. After transformation assay, the transformed cells were treated with various concentration of curcumin to evaluate cell viability, lactate dehydrogenase activity and DNA damage for 24h. The results revealed that curcumin decreased cell viability and increased the activity of lactate dehydrogenase enzyme in neoplastic transformed Balb/c 3T3 cells. In conclusion, the results demonstrated that curcumin has an anticancer effect on neoplastic transformed Balb/c 3T3 cells by causing DNA damage.

Reusable Enzymatic Strip for Detection of Arsenic

HIGHLIGHTS Arsenic is considered as one of the highly hazardous elements in the environment and a serious carcinogen for the human health. An enzymatic method has been described by using arsenite oxidase for arsenic detection. Residual activity of the immobilized enzyme was 43% of the initial activity after being recycled 10 times.

Abstract Arsenic is considered as one of the highly hazardous elements in the environment and a serious carcinogen for the human health. More attention has taken towards the arsenic due to its presence in ground water in India, China, Bangladesh, Inner Mongolia and several other regions of the world. It's been a challenge to remove arsenic due to the lack of its efficient detection approach in the complicated environmental matrix. The proposed method describes an enzymatic method for arsenic determination using arsenite oxidase, which catalyzes the oxidation of arsenite to arsenate. Hence, a colorimetric PVC strip with immobilized arsenite oxidase has been developed to detect the arsenic concentration and also having potential for the field-testing. The influence of the optimal conditions i.e. pH, temperature, storage stability, and reusability of free and immobilized enzyme were evaluated and compared. The results have shown that the stabilities were significantly enhanced compared with free counterpart. Residual activity of the immobilized enzyme was 43% of the initial activity after being recycled 10 times. We approve that this novel low cost immobilized carrier presents a new approach in large scale applications and expected to act as a model for establishment of indigenous arsenic sensor in miniature form.

Avaliação de risco à saúde humana devido a presença de arsênio e outros elementos em arroz no Brasil / Risk assessment from exposure to arsenic and other elements in rice from Brazil

Introdução: Arroz pode ser a principal fonte de exposição a arsênio inorgânico (iAs), que é carcinogênico e está associado a diversos efeitos não-carcinogênicos. Produtos feitos de arroz, como cereais infantis, e água para consumo podem ser importantes fontes de exposição a iAs. Embora o arroz seja um componente básico da dieta da população brasileira, há poucos estudos avaliando os riscos à saúde decorrentes da exposição ao iAs. Objetivo: Avaliar o risco da exposição a iAs e/ou outros elementos tóxicos e essenciais em arroz integral, arroz branco, cereais infantis, e água potável no Brasil, e identificar possíveis medidas para mitigar o risco. Método: O incremento de risco de câncer no tempo de vida (ILCR), o risco não-carcinogênico (HQ) e o hazard Index (HI) foram estimados através de análise probabilística com simulações de Monte Carlo. A concentração de elementos em arroz e cereais infantis foi obtida de pesquisas realizadas no Brasil, e a concentração de arsênio em água provém do monitoramento nacional de vigilância da qualidade da água. Resultados e discussão: O ILCR médio para exposição a iAs em arroz branco foi 1.3 × 10-04, arroz integral 5.4 × 10-06, e para exposição a chumbo (Pb) em arroz integral foi 2.5 x 10-8. O HQ para arroz foi estimado abaixo de 1 para todos os elementos, assim como o HI, sugerindo que efeitos não carcinogênicos não são esperados. O ILCR médio decorrente da exposição a iAs em água foi 6.5 × 10-05, acima do limite de 1 × 10-5, e o HQ foi inferior a 1. Cereais infantis feitos de arroz foram o tipo de cereal com maior ILCR (4.0 x 10-5) e com mais elementos com HQ acima de 1. Todos os cereais infantis apresentaram HQ acima de 1 para ao menos um elemento. Cadmio foi o elemento tóxico mais significativo, e zinco o elemento essencial mais relevante. Estimou-se que através de ações de mitigação o risco carcinogênico devido ao consumo de arroz poderia ser reduzido em até 68%, e para cereais infantis em 24%. O ILCR para arroz foi considerado elevado, ainda que as concentrações de iAs estejam dentro dos limites permitidos. O risco para arroz integral foi menor que para arroz branco, devido à baixa concentração de iAs nas amostras avaliadas, e as possíveis razões para isto foram exploradas, como o local do cultivo, práticas agrícolas e o tipo de cultivar de arroz. O risco carcinogênico e não-carcinogênico referente a exposição a Pb foi considerado baixo, entretanto nenhum nível de exposição a este elemento é considerado seguro. Conclusões: O ILCR para consumo de arroz, cereal infantil e água foi considerado elevado. O risco não-carcinogênico foi considerado elevado apenas para cereais infantis, incluindo elementos tóxicos e essenciais, e cereais infantis feitos de arroz apresentaram risco mais significativo. O consumo de água representou um menor risco carcinogênico, entretanto considerado não tolerável. Com o suporte de políticas públicas, medidas para reduzir os riscos relativos ao consumo de arroz e cereais infantis poderiam ter um impacto positivo para a saúde pública no Brasil.

Introduction: Rice can be the main source of exposure to inorganic arsenic (iAs), which is classified as carcinogenic and is also associated with non-cancer effects. Rice products, such as infant cereals, and drinking water are also important sources of exposure to iAs. Although rice is a staple food in Brazil, there have been few studies about the health risks for the Brazilian population. Objective: The objective of this study was to assess the risks of exposure to iAs and other toxic and essential elements from brown rice, white rice (only iAs), infant cereal (made of rice and different raw materials), and drinking water (only iAs) in Brazil, and to identify possible measures to mitigate those risks. Method: The incremental lifetime cancer risk (ILCR) and the non-cancer risk, or hazard quotient (HQ), and hazard index (HI) were calculated. A probabilistic analysis was performed with Monte Carlo simulation. Results and discussion: The mean ILCR was 1.3 × 10-04 for exposure to iAs in white rice and 5.4 × 10-06 for brown rice, and for exposure to Pb it was 2.5 x 10-8 for brown rice. The HQ was under 1 for all elements in brown rice, as the HI, suggesting that health effects are unlikely. The mean ILCR for exposure to iAs from drinking water was 6.5 × 10-05, above the tolerable value of 1 × 10-5 recommended by the World Health Organization, and the HQ was below 1. Rice cereal was the kind of infant cereal with highest ILCR (4.0 x 10-5) and with more elements with HQ above 1. All the infant cereals had an HQ above 1 for at least one element. Cd was the non-essential element more significative in this scenario, and Zn was the essential element more relevant. Various mitigation measures discussed in this dissertation are estimated to reduce the risk from rice consumption by 68%, and from infant cereal by 24%. The ILCR for white and brown rice was high, even though the iAs concentration in rice is below the maximum contaminant level. The risk for brown rice consumption was lower because the iAs concentrations were low in the brown rice samples evaluated, which possible reasons were explored, such as the location of cultivation, agricultural practices and the kind of rice cultivar. The estimated cancer and non-cancer risk from exposure to Pb is low, however no exposure to this element from diet is considered safe. Conclusions: The ILCR for rice, infant cereal and water consumption was considered high. The non-cancer risk was not tolerable only for infant cereal, including essential and non-essential elements, and rice cereal showed to be more concerning. Water consumption represents a small part of the risk for adults, although it was estimated to be not tolerable. With the support of public policies, measures to reduce these risks from rice and infant cereal would have a positive impact on public health in Brazil.

Evaluation of salivary protein patterns among a rural population exposed and non-exposed to arsenic-contaminated drinking water in areas of Tucumán (Argentina): a pilot study

Abstract Arsenic contamination in the environment and groundwater is a major global public health problem. Several researchers suggest that the toxicity of arsenic could be related to oral cancer development, usually resulting from potentially malignant lesions. During pathological processes, salivary proteins suffer modifications, which could lead to the discovery of new biomarkers. Objective To analyze the protein profile in human saliva samples from a rural population exposed to high levels of arsenic in drinking water and its association with potentially malignant lesions. Methodology This observational, analytic and cross-sectional design included 121 patients from the state of Graneros (Tucumán, Argentina). Arsenic concentration in drinking water was determined and, according to the values obtained, individuals were divided into 2 groups: exposed group and non-exposed group. Saliva samples were obtained, and total protein concentration was measured by Bradford method. Finally, Laemmli SDS-polyacrylamide gel electrophoresis was conducted to obtain the protein profile. Results Total protein concentration in saliva was lower in the exposed group than in the non-exposed group. Average areas of 20 and 42 KDa bands were significantly lower in exposed group than non-exposed group. Conclusion Chronic intake of high arsenic concentrations in drinking water produces changes in the salivary protein profile, which is associated with the presence of potentially malignant lesions.

Oral Squamous Cell Carcinoma Associated with Arsenic Exposure: A Case Series from Argentina / Carcinoma Oral de Células Escamosas Asociado con la Exposición al Arsénico: Una Serie de Casos de Argentina

ABSTRACT: Many areas of South America are directly affected by Arsenic (As) contaminated groundwater. A high percentage of the water samples taken in multiple areas of Argentina had As concentrations above the WHO level recommended guidelines. This condition was previously associated with an increased risk of chronic diseases, including different cancers. Long-term As exposure was proposed as a risk factor for Oral Squamous Cell Carcinoma (OSCC). The aim of this study is to present a series cases of Argentine patients diagnosed with OSCC who have consumed water contaminated with As for more than 10 years. Clinical data were obtained from the archive of Clinical Records Histories of the Oral Medicine Department of the Dentistry School, Universidad Nacional de Córdoba and Universidad Católica de Córdoba, Argentina. 15 cases of OSCC were included. The male: female sex ratio was 2:1. The average age was 66 years (31-89 years). Regarding location, the gum or edentulous alveolar ridge was the most prevalent site (6/15; 40 %), followed by the tongue margin. The average years of exposure to arsenical waters were 24 years (13 - 40 years of exposure). The majority of the presented cases were non drinkers non smokers. 60 % of the tumors were diagnosed at advanced stages. the epidemiological studies carried out in As-contaminated areas that address oral cancer should always incorporate the record of variables related to As exposure. Patients who live or lived at As-contaminated areas must be regularly followed up for early diagnosis of potentially malignant or malignant lesions. The high frequency of gum cancer among these cases, should raise awareness of periodontic specialists to perform a careful and thorough periodontal examination.

RESUMEN: Muchas regiones de América del Sur están directamente afectadas por aguas subterráneas contaminadas con arsénico (As). Un alto porcentaje de las muestras de agua tomadas en múltiples áreas de Argentina tenían concentraciones de As superiores al nivel aprobado por la OMS. Esta condición se asociaba previamente con un mayor riesgo de enfermedades crónicas, incluidos diferentes tipos de cáncer. La exposición a largo plazo se propuso como un factor de riesgo para el carcinoma oral de células escamosas (OSCC). El objetivo de este estudio es presentar una serie de casos de pacientes diagnosticados con OSCC que han consumido agua contaminada con As durante más de 10 años. Se obtuvieron datos clínicos del archivo de Historias de registros clínicos del Departamento de Medicina Oral de la Facultad de Odontología, Universidad Nacional de Córdoba y Universidad Católica de Córdoba, Argentina. Se incluyeron 15 casos de OSCC. La relación de género masculino: femenino fue de 2: 1. La edad promedio fue de 66 años (31-89 años). En cuanto a la ubicación, la encía o la cresta alveolar edéntula fue el sitio más frecuente (6/15; 40 %), seguido del borde de la lengua. El promedio de años de exposición a las aguas arsenicales fue de 24 años (13 - 40 años de exposición). La mayoría de los casos presentados fueron de pacientes no bebedores y no fumadores. El 60 % de los tumores fueron diagnosticados en etapas avanzadas. Los estudios epidemiológicos realizados en áreas contaminadas con As que abordan el cáncer oral siempre deben incorporar el registro de variables relacionadas con la exposición a As. Se debe hacer un seguimiento continuo de los pacientes que viven o que vivieron en áreas contaminadas con As para el diagnóstico temprano de lesiones potencialmente malignas. La alta frecuencia de cáncer de encías en estos casos, debe concienciar a los especialistas en periodoncia para que realicen un examen periodontal cuidadoso y completo.

Arsenic exposure in northern Mexican women / Exposición a arsénico en mujeres del norte de México

Abstract: Objective: To describe interindividual metabolism variations and sociodemographic characteristics associated to urinary arsenic, and to estimate the arsenic contamination in water from urinary total arsenic (TAs). Materials and methods: Women (n=1 028) from northern Mexico were interviewed about their sociodemographic characteristics and their urinary concentrations of arsenic species were measured by liquid chromatography. Inorganic arsenic (iAs) in water was estimated from urinary TAs. Results: Women were 20-88 years old. TAs in urine ranged from p10=3.41 to p90=56.93 μg/L; 74% of women had levels >6.4 μg/L. iAs in water varied from p10=3.04 to p90=202.12 μg/L; 65% of women had concentrations >10 μg/L, and 41%, concentrations >25 μg/L. Large variations in iAs metabolism were observed. TAs was significantly negatively associated with age and schooling, and positively with the state of residence. Conclusion: Exposure to iAs is an environmental problem in Mexico. Individual variations in metabolism are a challenge to design prevention and control programs.

Resumen: Objetivo: Describir las variaciones interindividuales del metabolismo y las características sociodemográficas asociadas con el arsénico urinario, así como estimar su contaminación en el agua. Material y métodos. Se entrevistó a 1 028 mujeres del norte de México; por cromatografía de líquidos se midieron los metabolitos urinarios de arsénico y, a partir de ellos, se estimó la concentración en agua. Resultados: Las mujeres tuvieron 20-88 años. El arsénico urinario varió de p10=3.41 a p90=56.93 μg/L; 74% de las mujeres tuvieron niveles >6.4 μg/L. El arsénico en agua varió de p10=3.04 a p90=202.12 μg/L; 65% de las mujeres tenían concentraciones >10 μg/L, y 41%, >25 μg/L. Se observaron amplias variaciones en el metabolismo del arsénico. El arsénico urinario se asoció negativamente con la edad y escolaridad, y positivamente con el estado de residencia. Conclusión: La exposición a arsénico es un problema ambiental en México. Las variaciones individuales en su metabolismo son un desafío para diseñar programas de prevención y control.

Bioremediation of heavy metals in food industry: application of Saccharomyces cerevisiae

Heavy metals are natural elements in the Earth's crust that can enter human food through industrial or agricultural processing, in the form of fertilizers and pesticides. These elements are not biodegradable. Some heavy metals are known as pollutants and are toxic, and their bioaccumulation in plant and animal tissues can cause undesirable effects for humans; therefore, their amount in water and food should always be under control. The aim of this study is to investigate the conditions for the bioremediation of heavy metals in foods. Various physical, chemical, and biological methods have been used to reduce the heavy metal content in the environment. During the last decades, bioremediation methods using plants and microorganisms have created interest to researchers for their advantages such as being more specific and environmentally friendly. The main pollutant elements in foods and beverages are lead, cadmium, arsenic, and mercury, which have their own permissible limits. Among the microorganisms that are capable of bioremediation of heavy metals, Saccharomyces cerevisiae is an interesting choice for its special characteristics and being safe for humans, which make it quite common and useful in the food industry. Its mass production as the byproduct of the fermentation industry and the low cost of culture media are the other advantages. The ability of this yeast to remove an individual separated element has also been widely investigated. In countries with high heavy metal pollution in wheat, the use of S. cerevisiae is a native solution for overcoming the problem of solution. This article summarizes the main conditions for heavy metal absorption by S. cerevisiae.

Screening and optimization of arsenic degrading bacteria and their potential role in heavy metal bioremediation / Triagem e otimização de bactérias que degradam arsê nicos e seu papel potencial na biorremediação de metais pesados

Industrialization has added extremely toxic metalloid arsenic into the environment which at high concentration severely threatens the biota. Naturally, some microbes possess the ability to bio-accumulate metals and also to transform arsenite (As III) a toxic form to a non-toxic arsenate As V. The present study aimed to isolate arsenic resistant bacterias from the arsenic contaminated soil and water. Among eleven bacterial isolates, three FAs 1, 4 and 9 exhibited tolerance against sodium arsenite at 100mM concentration by achieving growth of 7.48×109,1.57×109 and 2.23×109 C.F.U./ml, respectively. Optimization at differentconditions such as temperature, pH and arsenic concentration revealed high arsenic tolerance from isolate FAs 4 (5.33×108) at 37°C and FAs 1 (4.43×108 C.F.U./ml) at pH 7. Arsenic resistance at optimum conditions for the bacterial strains FAs 1, FAs 4 and FAs 9 showed maximum growth at 80mM concentration of arsenite. These bacterial isolates did not show redox ability to oxidize arsenite As III to arsenate As V. However bacterial isolates FAs 1, FAs 4 and FAs 9 were able to accumulate arsenic 39.16, 148 and 125 µ g/L on the 4th, 3rd and 5thday of incubation, respectively. The isolates FAs 1, FAs 4 and FAs 9 were identified as Gram negative non endospore forming rods. In future, these novel isolates possess a great potential in biotechnology field, as bioremediation of arsenic contaminated soil and water can be done by employing arsenic accumulating bacteria which is an eco-friendly and cost effective method.

A industrialização adicionou arsênico metalóide extremamente tóxico ao ambiente que, em alta concentração, ameaça severamente a biota. Naturalmente, alguns micróbios possuem a capacidade de bio-acumular metais e também transformar arsenito (As III) uma forma tóxica a um arsenato não-tóxico Como V. O presente estudo visa o isolamento de bactérias resistentes ao arsênico do solo contaminado com arsênico e água . Entre onze isolados bacterianos, três FAs 1, 4 e 9 exibiram tolerância à concentração de 100 mM de arseatura de sódio, obtendo crescimento de 7,48 × 109,157 × 109 e 2,23 × 109 C.F.U./ml, respectivamente. Otimização em diferentes condições como temperatura, pH e concentração de arsênio revelaram alta tolerância ao arsênico do isolado FAs 4 (5,33 × 108) a 37 ° C e FAs 1 (4,43 × 108 UFC / ml) em pH 7. Resistência ao arsênico em condições ótimas para as cepas bacterianas FAs 1, FAs 4 e FAs 9 apresentaram crescimento máximo na concentração de 80 mM de arsenito. Estes isolados bacterianos não mostraram capacidade redoxpara oxidar o arsenito As III para arseniar como V. No entanto, os isolados bacterianos FAs 1, FAs 4 e FAs 9 foram capazes de acumular arsênico 39,16, 148 e 125 µ g / L no 4º, 3º e 5º dia de incubação, respectivamente. Os isolados FAs 1, FAs 4 e FAs 9 foram identificados como bastonetes gram-negativos não endoscópicos. No futuro, esses novos isolados possuem um grande potencial no campo da biotecnologia, já que a biorremediação de solo e água contaminados com arsênico pode ser feita empregando-se bactérias que acumulam arsênico, o que é um método ecologicamente correto e econômico.

Evaluación de riesgo a la salud y contaminantes en agua de bebida: Importancia de la ingesta de agua / Evaluation of health risk and contaminants in drinking water: Importance of the water intake

Se evaluó la importancia del consumo diario de agua por ingesta en la evaluación de riesgo a la salud humana (ERS) de contaminantes presentes en agua subterránea de pozos domiciliarios en la ciudad de Azul, Argentina. El riesgo probabilístico acumulativo se calculó en base al modelo de la Agencia de Protección Ambiental de Estados Unidos (USEPA) para cuatro grupos de edad (5, 10, 15 años y adultos). Los resultados fueron comparados mediante la aplicación de un consumo diario de agua por ingesta estimado utilizado con frecuencia en la literatura frente a una cantidad ingerida local. De las seis variables usadas (Concentración de la sustancia peligrosa en el agua; Ingesta diaria de agua (I); Frecuencia de exposición; Duración de la exposición; Peso corporal del individuo expuesto; Factor de corrección para el tiempo promedio de exposición crónica), la Ifue la variable más influyente en el va­lor del riesgo presentando diferencias significativas entre los resultados derivados de ambos tipos de I. La diferencia más alta fue en los 5 años de edad, grupo que presentó un riesgo acumulado asociado con I local 98% más bajo respecto del riesgo calculado utilizando I basada en la literatura. La selección de la I tuvo un impacto significativo en los resultados del riesgo, lo que sugiere una cuidadosa elección de las variables de entrada al modelo de la evaluación del riesgo para evitar subestimaciones o sobreestimaciones.

We evaluated the importance of the daily consumption of water by ingestion on health risk assessment (HRA) from pollutants present in shallow groundwater from residential wells in the city of Azul, Argentina. The probabilistic cumulative risk was calculated based on the model of the United States Environmental Protection Agency (USEPA) for four age groups (5, 10, 15 years and adults). The results were compared by applying a daily consumption of water by estimated intake frequently used in the literature against a local ingested amount. From the six variables used (Concentration of the hazardous substance in water, Daily water intake (I), Frequency of exposure, Duration of exposure, Body weight of the exposed individual, Correction factor for the average time of chronic exposure), I was the most influential variable in the value of risk, presenting significant differences between the results de­rived from both types of I. The highest difference was in the 5 years of age, a group that presented an accumulated risk associated with local I 98% lower regarding the risk calculated using I based on the literature. The selection of I had a significant impact on risk outcomes, suggesting a careful choice of input variables to the risk assessment model to avoid underestimation or overestimation.

Bioleaching of realgar nanoparticles using the extremophilic bacterium Acidithiobacillus ferrooxidans DLC-5

BACKGROUND: This paper presents micro- and nano-fabrication techniques for leachable realgar using the extremophilic bacterium Acidithiobacillus ferrooxidans (A. ferrooxidans) DLC-5. RESULTS: Realgar nanoparticles of size ranging from 120 nm to 200 nm were successfully prepared using the highenergy ball mill instrument. A. ferrooxidans DLC-5 was then used to bioleach the particles. The arsenic concentration in the bioleaching system was found to be increased significantly when compared with that in the sterile control. Furthermore, in the comparison with the bioleaching of raw realgar, nanoparticles could achieve the same effect with only one fifth of the consumption. CONCLUSION: Emphasis was placed on improving the dissolvability of arsenic because of the great potential of leachable realgar drug delivery in both laboratory and industrial settings

Evaluación de la remoción de arsénico en agua superficial utilizando filtros domiciliarios / Evaluation of the arsenic removal in superficial waters using home filters

RESUMEN El objetivo del estudio fue evaluar filtros domiciliarios para remover arsénico presente en agua proveniente del río Sama. El sistema estuvo compuesto de un filtro tradicional de arena y un filtro con el material adsorbente de hierro cerovalente estabilizado en quitosano. La evaluación del sistema fue por un período de 12 semanas en 18 puntos de uso; las primeras ocho semanas se determinó la concentración de arsénico del agua filtrada empleando tiras reactivas, y las cuatro últimas fueron a través de espectrometría de absorción atómica (EAA-FIAS). Durante las primeras ocho semanas se redujo la concentración de arsénico en el rango de 0,005 y 0,025 mg/L, y durante las cuatro últimas en el rango de 0,001 y 0,052 mg/L, a partir de una concentración promedio de 0,51 mg/L. Se demostró que el sistema de filtración es eficiente para remover arsénico a condiciones naturales.

ABSTRACT The objective of the study was to evaluate home filters to remove arsenic present in waters coming from the Sama river. The system consisted of a traditional sand filter and a filter with the adsorbent zerovalent iron material stabilized in quitosan. The evaluation of the system lasted for a period of 12 weeks in 18 points of usage; the first eight weeks the arsenic concentration of the filtered water was determined using reactive strips, and the last four assessment was made through atomic absorption spectrometry (AAS). During the first eight weeks the arsenic concentration was reduced in a range of 0.005 and 0.025 mg/L, and during the last four weeks in the range of 0.001 and 0.052 mg/L, from an average concentration of 0.51 mg/L. This research showed that the filtration system is efficient to remove arsenic to natural conditions

Analysis of the association between bladder carcinoma and arsenic concentration in soil and water in southeast Brazil

ABSTRACT In approximately 50% of cases of bladder carcinoma, an associated predisposing factor can be established. The main factors are exposure to tobacco, arsenic (As) ore and aromatic compounds. Arsenic is a metalloid with a low average concentration in the earth's crust, and one of the most dangerous substances for human health. The present study aims to evaluate the incidence of hospitalization and mortality from bladder neoplasia and its possible association with As concentration in water and soil in two of the most critical regions of Brazil: the states of São Paulo and Minas Gerais. We have investigated bladder cancer hospitalization and mortality in the states of Sao Paulo and Minas Gerais during 2010-2014. Water and soil samples were analyzed and As concentrations were established. Data were obtained through the Department of Informatics of the Brazilian Unified Health System. Correlation was made with water samples from São Paulo and with data on soil analysis from Minas Gerais. The results revealed no direct association in the distinctive municipalities. Areas with high environmental As concentration had a low bladder cancer rate, while areas with normal as levels had similar cancer rates. The quantitative variables did not present a normal distribution (p < 0.05). In conclusion, we did not observe a correlation between as concentration in water or soil and bladder cancer's hospitalization and mortality rates in the states of São Paulo and Minas Gerais.