Arsenic speciation and valence / 中国中药杂志

As arsenic widely exists in nature and has been used in the pharmaceutical preparations, the traditional Chinese medicine(TCM) with arsenic include realgar(As_2S_2 or As_4S_4), orpiment(As_2S_3), and white arsenic(As_2O_3). Among the above representative medicine, the TCM compound formulas with realgar are utilized extensively. Just in Chinese Pharmacopoeia(2020 edition), there are 37 Chinese patent medicines including realgar. The traditional element analysis focuses on the detection of the total amount of elements, which neglects the study on the speciation and valence of elements. The activity, toxicity, bioavailability, and metabolic pathways of arsenic in vivo are closely related to the existence of its form, and different forms of arsenic have different effects on organisms. Therefore, the study on the speciation and valence of arsenic is of great importance for arsenic-containing TCMs and their compound formulas. This paper reviewed four aspects of the speciation and valence of arsenic, including property, absorption and metabolism, toxicity, and analytical assay.

Content and distribution of inorganic elements in Laminaria japonica based on ICP-MS and Micro-XRF / 中国中药杂志

In order to evaluate the composition and distribution characteristics of inorganic elements in Laminaria japonica, this study employed inductively coupled plasma mass spectrometry(ICP-MS) to detect the inorganic elements and used high performance liquid chromatography tandem ICP-MS(HPLC-ICP-MS) to determine the content of different arsenic species in L. japonica from diffe-rent origins. Micro X-ray fluorescence(Micro-XRF) was used to determine micro-area distribution of inorganic elements in L. japonica. The results showed that the average content of Mn, Fe, Sr, and Al was high, and that of As and Cr exceeded the limits of the national food safety standard. According to the results of HPLC-ICP-MS, arsenobetaine(AsB) was the main species of As contained in L. japonica. The more toxic inorganic arsenic accounts for a small proportion, whereas its content was 1-4 times of the limit in the national food safety standard. The results of Micro-XRF showed that As, Pb, Fe, Cu, Mn, and Ni were mainly distributed on the surface of L. japonica. Among them, As and Pb had a clear tendency to diffuse from the surface to the inside. The results of the study can provide a basis for the processing as well as the medicinal and edible safety evaluation of L. japonica.

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.

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.

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.

Cumulative Risk Assessment of Exposure to Heavy Metals through Aquatic Products in China / 生物医学与环境科学（英文）

Objective@#This study aimed to assess the risk of cumulative exposure to Pb, Cd, Hg, and iAs through aquatic products consumed by Chinese people.@*Methods@#Heavy metal concentration data were obtained from the national food contamination monitoring program during 2013-2017. Consumption data were derived from the China National Food Consumption Survey in 2014 and the relative potency factor (RPF) method was used to estimate cumulative exposure for neurotoxicity and nephrotoxicity.@*Results@#The results demonstrated that the cumulative exposure based on neurotoxicity was below the lower confidence limit on benchmark doses of lead (BMDL @*Conclusion@#The cumulative exposures of the 2-6 year-old group to the four heavy metals did not reach (but came close to) the corresponding safety threshold for both neurotoxicity and nephrotoxicity. Given that there are still other food sources of these four heavy metals, it is necessary to more closely study their cumulative health effects.

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.

Study on simultaneous determination of six arsenic species by HPLC-ICP-MS / 中国中药杂志

This study aims to establish a method for the determination of As B,As C,DMA,As( Ⅲ),MMA and As( Ⅴ) by using HPLC-ICP-MS. A Dioncx Ion PacTMAS7( 4 mm×250 mm) column was used for the HPLC-ICP-MS method. The mobile phase was 100 mmol·L-1 ammonium carbonate-1. 5 mmol·L-1 ammonium dibasic phosphate( gradient elution) at a flow rate of 1 m L·min-1. The injection volume was 10 μL. The linear relationships of As B,As C,DMA,As( Ⅲ),MMA,As( Ⅴ) were good with the concentration of10-500 μg·L-1. The average recovery rates( n = 6) were 105. 7%,100. 5%,102. 9%,105. 7%,100. 2%,92. 69%. The RSD were0. 50%,2. 4%,0. 93%,1. 3%,0. 89%,1. 5%. The precision and repeatability of this method were good. In this study,six forms of arsenic were separated effectively by this method. With methodological validation and sample determination,this method can be used to determine the morphological valence of arsenic in content determination.

Analysis of arsenic speciation in Sepiae Endoconcha and research on its limit standard / 中国中药杂志

Sepiae Endoconcha is a common marine animal medicine,which generally contains high concentration of arsenic( As).The Chinese Pharmacopoeia( 2010 edition,part I) stipulated that the total As content of Sepiae Endoconcha should not exceed 2 mg·kg~(-1),while this limit was revised to 10 mg·kg~(-1) in the 2015 edition. So far,there is no research on the speciation of As in Sepiae Endoconcha,which made it hard to accurately evaluate its security risk. In this study,32 batches of Sepiae Endoconcha from different sources were collected. The safety risk assessment was carried out by determining the total As content and As speciation,inorganic As[As( Ⅲ),As( Ⅴ) ]and organic As( MMA,DMA,As C,As B) by HPLC-ICP-MS,and then the limit standard was discussed. The results showed that As B was the main form of As in Sepiae Endoconcha,followed by DMA and As( Ⅴ) ． Of the 32 batches of Sepiae Endoconcha,9 batches( accounting for 28%) were detected possessing i As. The maximum concentration of As( Ⅲ) was 103. 3 μg·kg~(-1),and the maximum concentration of As( Ⅴ) was 222. 4 μg·kg~(-1). According to the limit of i As in food,18. 75% of the samples exceeded the standard. The results indicate that there is no simple positive correlation between total As and As morphology in Sepiae Endoconcha. Besides,there is a risk in the total As limit,especially after the relaxation of the total As limit. The problem of high i As content caused by pollution and other factors is difficult to regulate. Since the toxicity of inorganic As is much higher than that of organic As,it is of great practical significance to establish inorganic As form limits in Sepiae Endoconcha.

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.

Ingesta de arsénico: el impacto en la alimentación y la salud humana / Arsenic Intake: Impact in Human Nutrition and Health

RESUMEN El arsénico es un elemento que se encuentra ampliamente distribuido en todo el medio ambiente. Sus compuestos se hallan principalmente en estado de oxidación pentavalente y trivalente; y en formas inorgánicas y orgánicas. Las especies arsenicales varían en su grado de toxicidad, siendo los compuestos inorgánicos más tóxicos que los orgánicos, y los compuestos trivalentes más tóxicos que los pentavalentes. Habría interconversión entre las especies menos tóxicas a otras más toxicas y los métodos de cocción y de procesamiento podrían afectarla. El arsénico es un agente carcinogénico y ocasiona múltiples efectos negativos sobre la salud humana a corto y largo plazo. La exposición humana no ocupacional al arsénico se da principalmente por agua y alimentos. La normativa es variable para cada país, y se basa en los estándares de la OMS, Codex Alimentarius y la Unión Europea. Muchos estudios se enfocan en determinar el contenido total de arsénico mas no identifican las especies arsenicales en alimentos. A nivel global, pescado y mariscos, pollo, carnes, arroz y algas marinas tienen niveles elevados de arsénico. En Perú, hay escasos estudios sobre contenido de arsénico total y especies arsenicales en alimentos a pesar que tenemos zonas con altos niveles de contaminación ambiental. El objetivo de esta revisión es discutir la exposición al arsénico a través de la ingesta de alimentos y agua, la normativa relacionada, toxicidad, consecuencias en la salud humana y principales alimentos que contribuyen a su ingesta.

ABSTRACT Arsenic is an element that is widely distributed throughout the environment. Its compounds are mainly in the state of pentavalent and trivalent oxidation; and in inorganic and organic forms. Arsenical species vary in their degree of toxicity, with inorganic compounds being more toxic than organic and trivalent compounds more toxic than pentavalent compounds. There would be interconversion between the less toxic species and other more toxic species and the cooking and processing methods could affect it. Arsenic is a carcinogenic agent and causes multiple negative effects on human health in the short and long term. Non-occupational human exposure to arsenic occurs mainly through water and food. The regulation is variable for each country and is based on WHO standards, the Codex Alimentarius, and the European Union. Many studies focus on determining the total arsenic content but do not identify arsenical species in foods. Globally, fish and seafood, chicken, meat, rice, and seaweed have high levels of arsenic. In Peru, there are few studies on total arsenic content and arsenical species in food despite the fact that we have areas with high levels of environmental contamination. The objective of this review is to discuss exposure to arsenic through food and water intake, related regulations, toxicity, consequences on human health and main foods that contribute to its intake.

Effect of phosphorus on arsenic uptake and metabolism in rice cultivars differing in phosphorus use efficiency and response

ABSTRACT A hydroponic experiment was carried out to investigate the effect of phosphorus (P) nutrition on arsenic (As) uptake and translocation within the seedlings of rice cultivars. The experiment occurred in three stages: I 5 days of acclimatization (nutritive solution); II 10 days under P (0.0 and 0.09 mM) and As (0.0 and 100 mM) treatments; III 5 days under recovery. The As exposure had significant effect reducing dry weights of shoots or roots, resulted in elevated concentrations of As in shoot tissues. BR-IRGA 409 showed the highest susceptibility to As in biomass production and root system parameters regardless the P level. This cultivar showed contrasting responses of As translocation to shoot tissue dependent on P levels, with the highest As concentration under low P and lowest under normal P levels. P nutrition was most striking on plants recovery for all cultivars under As exposure. Clearer separation of cultivars for phosphorus use efficiency (PUE) occurred at lower shoot P contents, that was, at higher levels of P deficiency stress. IRGA 424 showed higher PUE as compared to the others cultivars. Our results go some way to understanding the role of P nutrition in controlling the effects of As in rice shoots.

Riesgos potenciales de salud por consumo de agua con arsénico en Colima, México / Potential health risks from consumption of water with arsenic in Colima, Mexico

Resumen: Objetivo: Estimar los riesgos potenciales de salud debidos a la ingestión crónica de arsénico (As) en agua en Colima, México. Material y métodos: Se muestrearon aleatoriamente 36 pozos en 10 acuíferos locales. El análisis se hizo mediante ICP-OES siguiendo estándares internacionales. Se realizó una interpolación geoestadística con ArcGIS, implementando un modelo de ponderación del inverso de la distancia, para estimar la ruta de exposición de consumo en cada localidad. Se calcularon los coeficientes de peligro (HQ) y riesgo carcinogénico (R). Resultados: El HQ promedio ponderado de As para Colima es 2.41. Existen valores de HQ>1 para As que indican efectos adversos no carcinogénicos para la salud por ingestión continua y prolongada de agua; esto podría afectar a 183 832 individuos en el estado. El riesgo calculado de desarrollar cáncer debido a las concentraciones de arsénico en aguas subterráneas (R) es de 1.089E-3; estadísticamente esto podría ocasionar 446 casos de cáncer. Conclusiones: Los niveles actuales de arsénico en el agua de pozo incrementan los riesgos carcinogénicos y no carcinogénicos de salud humana en Colima.

Abstract: Objective: To estimate potential health risks due to chronic ingestion of arsenic from groundwater in Colima, Mexico. Materials and methods: Samples were randomly taken in 36 wells from 10 local aquifers. Analysis was performed by ICP-OES following international standards. Geostatistical interpolation was performed with ArcGIS, implementing a model weighting inverse distance to estimate arsenic routes of exposure and consumption on each locality. The Hazard Quotient Ratio (HQ) and carcinogenic risk (R) for As were estimated. Results: The weighted average HQ for arsenic in Colima is 2.41. There are HQ> 1 values indicating adverse non-cancer health effects by continuous and prolonged intake of water with arsenic, which could affect 183 832 individuals in the state. The risk of developing any type of cancer among the population in this study due to high arsenic concentrations in groundwater (R) is 1.089E-3, which could statistically cause 446 cases of cancer. Conclusions: Current levels of arsenic in groundwater increase carcinogenic and non-carcinogenic human health risks in Colima.

Environmental Source of Arsenic Exposure / 예방의학회지

Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.

Environmental Source of Arsenic Exposure / 예방의학회지

Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.

Concentración de Hg, Pb, Cd, Cr y As en hígado de Carcharhinus limbatus (Carcharhiniformes: Carcharhinidae) capturado en Veracruz, México

Concentration of Hg, Pb, Cd, Cr and As in liver Carcharhinus limbatus (Carcharhiniformes: Carcharhinidae) captured in Veracruz, Mexico. Pollution by heavy metals in marine ecosystems in the Gulf of Mexico is one of the hardest conservation issues to solve. Sharks as top predators are bioindicators of the marine ecosystem health, since they tend to bioaccumulate and biomagnify contaminants; they also represent a food source for local consumption. Thus, the objective of this study was to study the possible presence of heavy metals and a metalloid in livers of Carcharhinus limbatus. For this, a total of 19 shark livers were taken from animals captured nearby Tamihua, Veracruz, Mexico from December 2007 to April 2008. 12 out of the 19 captured sharks were males, one was an adult female, three were juvenile males, and three juvenile females. Four heavy metals (Hg, Pb, Cd, and Cr) and one metaloid (As) were analyzed in shark livers using an atomic absorption spectrophotometry with flame and hydride generator. Our results showed that the maximum concentrations found were: Hg=0.69mg/kg, Cd=0.43mg/kg, As=27.37mg/kg, Cr=0.70mg/kg. The minimum concentrations found were: As=14.91mg/kg, Cr=0.35mg/kg. The Pb could not be determined because the samples did not have the spectrophotometer minimum detectable amount (0.1mg/kg). None of the 19 samples analyzed showed above the permissible limits established by Mexican and American laws. There was a correlation between shark size and Cr and As concentration (Pearson test). The concentration of Cr and As was observed to be higher in bigger animals. There was not a significant difference in heavy metals concentration between juveniles and adults; however, there was a difference between males and females. A higher Cr concentration was found in females when compared to males. None of the samples exceed the maximum limit established by the laws of Mexico and the United States of America. Much longer studies are needed with C. limbatus and other species caught in the region, in order to determine the degree of contaminants exposure in aquatic ecosystems and to identify potential health risks to consumers.

La contaminación de los ecosistemas marinos y costeros por metales pesados en el Golfo de México es uno de los problemas que afectan a los recursos naturales del medio acuático. Los tiburones por situarse en niveles tróficos superiores de la red alimenticia acumulan y magnifican cantidades considerables de contaminantes. Por esta razón, el objetivo de este trabajo fue determinar la concentración de cuatro metales pesados (Hg, Cd, Pb y Cr) y un metaloide (As) en el tiburón punta negra (Carcharhinus limbatus) por medio de espectrofotometría de absorción atómica con flama y generador de hidruros. Se muestrearon 19 hígados de tiburones capturados cerca de Tamiahua, Veracruz entre noviembre 2007 y marzo 2008, de los cuales 12 fueron machos adultos, una hembra adulta, tres machos jóvenes y tres hembras jóvenes. Las concentraciones máximas registradas para cada metal fueron: Hg=0.69mg/ kg, Cd=0.43mg/kg, As=27.37mg/kg, Cr=0.35mg/kg. El Pb no fue detectado, no al menos la cantidad mínima de detección requerida por el espectrofotómetro de absorción atómica (0.1mg/kg). Ninguna de las muestras analizadas rebasó los límites máximos permisibles por las leyes mexicanas y americanas.

Riesgo sanitario de la población vulnerable expuesta al arsénico en la provincia de Buenos Aires, Argentina / Health risk for the vulnerable population exposed to arsenic in the province of Buenos Aires, Argentina

OBJETIVO: Analizar la concentración de arsénico en agua recolectada en localidades de la provincia de Buenos Aires, Argentina, y su relación epidemiológica con factores de susceptibilidad y patologías asociadas. MÉTODOS: Se cuantificó la concentración de arsénico en 152 muestras provenientes de 52 localidades de Buenos Aires durante el período 2003-2008 mediante generación de hidruros-espectrofotometría de absorción atómica. Se construyó un índice compuesto de salud (ICS) considerando el contenido de arsénico, el porcentaje de hogares con necesidades básicas insatisfechas (NBI) y el de viviendas sin acceso al agua de red. A partir del ICS se definieron zonas de riesgo que fueron asociadas con la mortalidad por tumores malignos relacionados con el arsénico. RESULTADOS: Las concentraciones de arsénico se ubicaron en un rango amplio, desde 0,3 hasta 187 µg/L, con una mediana de 40 µg/L. El 82 por ciento de las muestras presentaron niveles de arsénico superiores al valor límite aceptable de 10 µg/L, y más de la mitad de ellas provenían de agua de red. La mortalidad promedio (defunciones/100 000 habitantes) por tumores en los departamentos estudiados fue mayor en los varones que en las mujeres: vías respiratorias (310 frente a 76), vías urinarias (44 frente a 11) y piel (21 frente a 11), respectivamente. Las regiones de mayor concentración de arsénico y pobreza, junto con la falta de agua de red, presentaron un riesgo relativo incrementado de 2 a 4 veces. CONCLUSIONES: La caracterización realizada a través del índice compuesto de salud sintetizó el riesgo sanitario de la exposición al arsénico de la población con niveles de carencia socioeconómica de una amplia región de la provincia de Buenos Aires.

OBJECTIVE: To analyze the concentration of arsenic in water collected in localities of the province of Buenos Aires, Argentina, and the epidemiological relationship of that concentration to factors of susceptibility and associated pathologies. METHODS: In 152 samples from 52 localities of Buenos Aires from 2003-2008, the concentration of arsenic was quantified through the generation of hydride spectrophotometry of atomic absorption. A composite index of health (CIH) was constructed using the content of arsenic and the percentages of households with unmet basic needs and dwellings without access to the potable water. Through the CIH, risk areas associated with mortality from malignant neoplasms related to arsenic were defined. RESULTS: Concentrations of arsenic spanned a broad range from 0.3 to 187 mg/L, with a median of 40 mg/L. Of the samples, 82 percent presented levels of arsenic higher than the acceptable limit of 10 mg/L, and more than half of those came from households with potable water connections. In the departments studied, the average mortality (deaths/100 000 inhabitants) from tumors was greater in men than in women: respiratory tract (310 versus 76), urinary tract (44 versus 11), and skin (21 versus 11), respectively. The regions with greater concentrations of arsenic and of poverty, together with the lack of potable water connections, had a two-to-four times greater risk. CONCLUSIONS: The findings from the composite index of health summarized the health risk from exposure to arsenic for lower socioeconomic levels of the population for a broad area of the province of Buenos Aires.