Association between urinary arsenic level and serum testosterone in Chinese men aged 18 to 79 years / 中华预防医学杂志

Objective: To investigate the association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years. Methods: A total of 5 048 male participants aged 18 to 79 years were recruited from the China National Human Biomonitoring (CNHBM) from 2017 to 2018. Questionnaires and physical examinations were used to collect information on demographic characteristics, lifestyle, food intake frequency and health status. Venous blood and urine samples were collected to detect the level of serum total testosterone, urinary arsenic and urinary creatinine. Participants were divided into three groups (low, middle, and high) based on the tertiles of creatinine-adjusted urinary arsenic concentration. Weighted multiple linear regression was fitted to analyze the association of urinary arsenic with serum total testosterone. Results: The weighted average age of 5 048 Chinese men was (46.72±0.40) years. Geometric mean concentration (95%CI) of urinary arsenic, creatinine-adjusted urinary arsenic and serum testosterone was 22.46 (20.08, 25.12) μg/L, 19.36 (16.92, 22.15) μg/g·Cr and 18.13 (17.42, 18.85) nmol/L, respectively. After controlling for covariates, compared with the low-level urinary arsenic group, the testosterone level of the participants in the middle-level group and the high-level group decreased gradually. The percentile ratio (95%CI) was -5.17% (-13.14%, 3.54%) and -10.33% (-15.68%, -4.63). The subgroup analysis showed that the association between the urinary arsenic level and testosterone level was more obvious in the group with BMI<24 kg/m2 group (Pinteraction=0.023). Conclusion: There is a negative association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years.

Associations between urinary heavy metal concentrations and blood pressure in residents of Asian countries

BACKGROUND@#Previous studies have suggested that exposures to heavy metals (arsenic, cadmium, lead, and selenium) may be associated with differences in blood pressure. However, the findings of these studies have been inconsistent. This study was performed to examine the associations between urinary heavy metal concentrations and blood pressure among residents of four Asian countries (Bangladesh, Indonesia, Nepal, and Vietnam).@*METHODS@#This cross-sectional study examined 1899 adults in four Asian countries. Urinary concentrations of heavy metals were measured by inductively coupled plasma mass spectrometry. A questionnaire survey was administered regarding individual characteristics. Anthropometric measurements (height and weight) were performed. Systolic and diastolic blood pressures were measured after a short rest. Multiple linear regression models were applied to investigate associations between urinary heavy metal concentrations and blood pressure after adjustments for age, sex, and body mass index.@*RESULTS@#The geometric means of the urinary concentrations of arsenic, cadmium, lead, and selenium were 84.6, 0.885, 2.09, and 16.5 μg/g creatinine, respectively. The urinary arsenic concentrations were slightly higher than those typically reported in non-polluted populations, while urinary cadmium, lead, and selenium concentrations were equivalent or slightly lower. The urinary lead concentrations were positively associated with both systolic and diastolic blood pressure, but urinary selenium concentrations were negatively associated with them.@*CONCLUSIONS@#Variations in the urinary concentrations of lead and selenium were associated with blood pressure at low levels of exposure/intake.

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.

Concentraciones de Arsénico Urinario en Pobladores de dos Distritos de la Región Tacna, Perú, 2017 / Urinary Arsenic Concentrations In Adult Population Of Two Districts From The Tacna Region, Peru, 2017

RESUMEN Objetivos . Determinar la concentración de arsénico (As) total urinario en pobladores adultos de dos distritos de la región Tacna. Materiales y métodos . Estudio transversal realizado en los distritos de Cairani y Camilaca, en la provincia de Candarave en la región Tacna, Perú, para lo cual se recolectaron 103 y 71 muestras de orina, respectivamente. La concentración de As urinario se determinó por el método de digestión en microondas e inyección de flujo en espectrofotometría de absorción atómica. Resultados . La mediana de concentración de As urinario en Cairani fue de 601,6 μg/g creatinina (RIC 407,3-847,1) y en Camilaca fue de 30,2 μg/g creatinina (RIC 21,4 - 39,7). El 100 % (103) de las muestras procedentes de Cairani y el 80,3 % (57) de las muestras de Camilaca superaron los valores referenciales de toxicidad. Asimismo, los pobladores de Cairani superan en 30 veces, y los de Camilaca en 1,5 veces, los valores de toxicidad para As. Conclusiones . La población adulta de los distritos de Cairani y Camilaca de la provincia de Candarave, de la región Tacna, tienen concentraciones de As urinario superiores a los valores referenciales de toxicidad establecidos por la Organización Mundial de la Salud.

ABSTRACT Objectives . To determine the concentration of total urinary arsenic (As) in the adult population of two districts in the Tacna region. Materials and Methods . A cross-sectional observational study conducted in the districts of Cairani and Camilaca, in the province of Candarave in the Tacna region, Peru. For the study 103 and 71 urine samples were collected. The concentration of urinary As was determined by the method of microwave digestion and flow injection in atomic absorption spectrophotometry (FIAS-AAS). Results . In the Cairani district, a median urinary arsenic concentration of 601.61 μg/g creatinine (IQR: 407,3 - 847,1) was obtained; and for Camilaca, a median of 30.24 μg/g creatinine was obtained (IQR: 21,4 - 39,7). The residents of Cairani and Camilaca exceed 30 and 1.5 times, respectively, the toxicity reference values (TRV) for arsenic. Conclusions . The adult population of the districts of Cairani and Camilaca in the province of Candarave of the Tacna region has urinary As concentrations exceeding the toxicity reference values (TRV) established by the World Health Organization (WHO).

Polimorfismos del gen Arsénico 3 Metiltransferasa (As3MT) y la eficiencia urinaria del metabolismo del arsénico en una población del norte de México / Polymorphisms of the Arsenite Methyltransferase (As3MT) gene and urinary efficiency of arsenic metabolism in a population in northern Mexico

RESUMEN El objetivo del estudio fue evaluar la relación de los polimorfismos rs11191439 y rs3740393 del gen Arsénico 3 Metiltransferasa (As3MT) con los perfiles de excreción urinaria de arsénico, en una población del norte de México. Se realizó un estudio transversal con 102 participantes de 14 a 75 años en la Comarca Lagunera, México. Se determinó la especiación de los metabolitos urinarios de arsénico y extracción de ADN, el análisis y amplificación de los polimorfismos se realizó por PCR tiempo real. Se realizó un análisis descriptivo y se evaluó las diferencias en las concentraciones de arsénico urinario por sexo y genotipo. La mediana de concentración de arsénico en el agua fue de 82 μg/L, los niveles de excreción urinaria del ácido dimetilarsínico (DMA) fueron más altos en mujeres que en los hombres. Los portadores de la variante genética CC del gen As3MT (rs3740393) presentaron concentraciones urinarias superiores de ácido monometilarsónico (p=0,01) y DMA (p=0,05).

ABSTRACT The aim of this study was to assess the relationship of the rs11191439 and rs3740393 polymorphisms of the Arsenite Methyltransferase (As3MT) gene with the arsenic urinary excretion profiles in a population in northern Mexico. A crosssectional study was conducted with 102 participants between the ages of 14 and 75 in Comarca Lagunera, Mexico. Speciation of the arsenic urinary metabolites was determined, and DNA was extracted; analysis and amplification of the polymorphisms was made by PCR in real time. A descriptive analysis was carried out and the differences in the urinary arsenic concentrations were assessed according to sex and genotype. The median concentration of arsenic in water was 82 μg/L; the levels of urinary excretion of dimethylarsinic acid (DMA) were higher in women than in the men. The carriers of the CC genetic variant of the As3MT (rs3740393) gene showed higher urinary concentrations of methylarsinic acid (p=0.01) and DMA (p=0.05).

Environmental Exposure to Arsenic, Lead, and Cadmium in People Living near Janghang Copper Smelter in Korea

Concentrations of heavy metals exceed safety thresholds in the soil near Janghang Copper Refinery, a smelter in Korea that operated from 1936 to 1989. This study was conducted to evaluate the level of exposure to toxic metals and the potential effect on health in people living near the smelter. The study included 572 adults living within 4 km of the smelter and compared them with 413 controls group of people living similar lifestyles in a rural area approximately 15 km from the smelter. Urinary arsenic (As) level did not decrease according to the distance from the smelter, regardless of gender and working history in smelters and mines. However, in subjects who had no occupational exposure to toxic metals, blood lead (Pb) and cadmium (Cd) and urinary Cd decreased according to the distance from the smelter, both in men and women. Additionally, the distance from the smelter was a determinant factor for a decrease of As, Pb, and Cd in multiple regression models, respectively. On the other hands, urinary Cd was a risk factor for renal tubular dysfunction in populations living near the smelter. These results suggest that Janghang copper smelter was a main contamination source of As, Pb, and Cd, and populations living near the smelter suffered some adverse health effects as a consequence. The local population should be advised to make efforts to reduce exposure to environmental contaminants, in order to minimize potential health effects, and to pay close attention to any health problems possibly related to toxic metal exposure.

Arsenic Exposure and Prevalence of Diabetes Mellitus in Korean Adults

It has been suggested that there is an association between environmental, low-level arsenic exposure and the risk of diabetes mellitus (DM), but little research has been conducted. Here, the glucose tolerance status and urinary creatinine adjusted total arsenic concentrations were analyzed in 3,602 subjects > or = 20 yr of age who were registered for the Korea National Health and Nutrition Examination Survey, 2008-2009. Various demographic parameters were associated with urinary arsenic concentrations. After adjusting for these variables, urinary arsenic concentrations in subjects with DM were significantly higher than those in subjects with normal glucose tolerance and those with impaired fasting glucose (P or = 193.4 microg/g creatinine, respectively, following multivariate adjustment. Furthermore, the urinary total arsenic concentration was inversely associated with the insulin secretion index, HOMA2 %B (beta = -0.033, P = 0.032). These findings suggest that arsenic exposure, possibly involving beta cell dysfunction, is associated with an increased risk of DM in the Korean population.

Cuantificacion de arsenico por inyeccion en flujo-generacion de hidruros-espectrometria de absorcion atomica (IF-GH-EAA) previa derivatizacion con L-cisteina. Validacion y comparaci¨®o intermetodologica utilizando dos tecnicas de referencia / Arsenic quantitation by flow injection-hydride generation- atomic absorption spectrometry (FI-HG-AAS) after L-cysteine derivatization. Validation and inter-methodological comparison using two reference techniques

La presencia de Arsenico (As) en aguas de consumo representa una problematica para la salud publica en muchas regiones del mundo, incluida la Argentina. La cuantificacion de arsenico en agua de bebida y en orina se utiliza para evaluar la exposicion a este contaminante. El presente trabajo tuvo como objetivo la validacion metodologica de una tecnica para la cuantificacion de especies del As [AsV + AsIII + acido monometilarsonico (MMA) + acido dimetilarsinico (DMA)] por inyeccion en flujo-generacion de hidruros-espectrometria de absorcion atomica (IF-GH-EAA), previa derivatizacion con L-cisteina. Los resultados fueron comparados con los obtenidos utilizando dos metodologias de referencia, generacion de hidruros-espectrometria de absorcion atomica (GH-EAA) para muestras de aguas y orina, y cromatografia de alta resolucion ¨Cgeneracion de hidruros-espectrometr¨ªa de absorcion atomica (HPLC-GH-EAA) para muestras de orina. Ademas, se evaluo la selectividad de la cuantificacion por IF-GH-EAA, en presencia de otras especies quimicas del As, provenientes del consumo de alimentos producto de la pesca, a traves de un ensayo biologico. Los niveles de As hallados en las muestras de agua y de orina utilizando las tecnicas de referencia presentaron un rango de 6 a 176 ¦Ìg/L y de 143 a 3312 ¦Ìg/g de creatinina, respectivamente. Los coeficientes de Pearson resultantes de la comparacion de los datos obtenidos por IF-GH-EAA, con los logrados por los metodos de referencia fueron r = 0,9976 y r = 0,9422, para agua y orina, respectivamente. Los resultados de la prueba biologica indicaron un mayor nivel de As, debido al consumo de alimentos producto de la pesca, cuando las muestras de orina fueron previamente mineralizadas (GH-EAA), con la consecuente sobreestimacion del contenido de As proveniente del consumo de As inorganico. Este aumento no se observo cuando estas fueron analizadas por IF-GH-EAA ...

The presence of arsenic (As) in drinking water is a public health concern in many regions of the world, including Argentina. Quantification of arsenic in drinking water and urine are used to assess exposure to this pollutant. This study aimed to validate a methodology for the quantification of As species [AsV + AsIII + acid monometilarsonico (MMA) + dimetilarsinico acid (DMA)] by flow injection-hydride generation-atomic absorption spectrometry (FI-HG-AAS), after derivatization with L-cysteine. The results were compared with those obtained using two methods of reference, hydride generation-atomic absorption spectrometry (HG-AAS) for water and urine samples, and high performance liquid chromatography-hydride generation-atomic absorption spectrometry (HPLC-HG-AAS) for urine samples. In addition, the selectivity of quantification by FI-HG-AAS in the presence of other chemical species of As, from fishery products intake, was evaluated through a biological assay.The As level found in water and urine samples, using the techniques of reference, showed a range from 6 to 176 ¦Ìg/L and from 143 to 3312 ¦Ìg/g creatinine, respectively. Pearson coefficients resulting from the comparison of data obtained by FI-HG-AAS with those achieved by the reference methods were r = 0.9976 and r = 0.9422 for water and urine, respectively. The results of the biological test showed a higher level of As, due to consumption of food fishery product, when urine samples were previously mineralized (HG-AAS), with consequent overestimation of the inorganic arsenic consumption. When these samples were analyzed by FI-HG-AAS this fact was not observed, and the values were comparable to baseline level prior to consumption ...

Arsenic exposure assessment of children living in a lead mining area in Southeastern Brazil / Avaliação da exposição de crianças ao arsênio em área de mineração de chumbo na Região Sudeste do Brasil

Environmental contamination by arsenic compounds in the Ribeira River Valley, São Paulo, Brazil has already been observed. Lead mining and refining activities had been carried on since late colonial times and finished recently, at the end of 1995. The source of As in the region is known to be mainly from arsenopirite geological presence in the lead ore. Chronic exposure to arsenic compounds may cause peripheral vascular disorders, hyperpigmentation, hiperkeratosis and cancer of the skin, bladder, lung, liver and other internal organs. The purpose of this study was to assess children exposure to arsenic from environmental sources in the region. Urine samples from children between 7 to 14 years old were collected at the following localities: Cerro Azul (Paraná); urban areas of Ribeira (São Paulo) and Adrianópolis (Paraná); Vila Mota neighborhood (rural area of Adrianópolis) and Serra neighborhood (Iporanga, São Paulo), identified as groups 1, 2, 3 and 4, respectively. Group 1 was considered as non-exposed control group. Toxicologically relevant forms of As were determined by atomic absorption spectrometry with hydride generation system. The median values of urine arsenic levels obtained in groups 1, 2, 3 and 4 were respectively: 3.60, 6.30, 6.41 e 8.94μg/L.

Contaminação ambiental por compostos de arsênio no Vale do Ribeira, São Paulo, Brasil, tem sido já observada. As atividades de mineração e refinamento do chumbo têm ocorrido desde a época colonial e foram encerradas recentemente, no final de 1995. A principal fonte de arsênio na região é arsenopirita que ocorre geologicamente no minério de chumbo. Exposição crônica aos compostos de arsênio podem causar desordens vasculares periféricas, hiperpigmentação, hiperqueratose, além de câncer de pele, bexiga, pulmão, fígado e outros órgãos. O objetivo do presente estudo foi avaliar a exposição de crianças ao arsênio proveniente de fontes ambientais na região. Amostras de urina de crianças entre 7 e 14 anos foram coletadas das seguintes localidades: Município de Cerro Azul (Paraná); região urbana dos municípios de Ribeira (São Paulo) e Adrianópolis (Paraná); bairro Vila Mota (área rural de Adrianópolis) e bairro Serra (Ipiranga, São Paulo), identificados como grupos 1, 2, 3 e 4, respectivamente. O grupo 1 foi considerado não exposto (grupo controle). As formas de arsênio toxicologicamente relevantes foram determinadas por espectrometria de absorção atômica com sistema de geração de hidretos. Os valores medianos de arsênio obtidos nos grupos 1, 2, 3 e 4 foram iguais a 3,60, 6,30, 6,41 e 8,9μg/L.

Optimización y validación metodológica de la cuantificación de arsénico por inyección en flujo -generación de hidruros- espectrometría de absorción atómica (IF-GH-EAA) previa derivatización con L-cisteína / Optimization and validation method for arsenic quantification by flow injection-hydride generation - atomic absorption spectrometry (FI-HG-AAS) after L-cysteine derivatization

El arsénico (As) es un contaminante natural que afecta una amplia zona de Argentina. El nivel de As en agua de consumo es utilizado para evaluar la fuente de exposición y en orina para evaluar exposición a este tóxico. El presente trabajo tuvo como objetivo la optimización y validación metodológica de una técnica para la cuantificación de As [As suma = As inorgánico (AsI) + especies metiladas: ácido monometilarsónico (MMA) y ácido dimetilarsónico (DMA)], producto del metabolismo del AsI, por inyección en flujo- generación de hidruros- espectrometría de absorción atómica (IF-GH-EAA), previa derivatización con L-cisteína. La recuperación de las especies estudiadas: AsI (AsIII y AsV), MMA y DMA fue cercana al 100% en todos los casos. Los límites de detección y cuantificación encontrados fueron para agua y orina: 2 y 3 µg/L; 5 y 8 µg/L respectivamente y el rango dinámico de trabajo establecido fue desde 5 a 75 µg/L, permitiendo cuantificar As en muestras de agua cercanos a los estándares internacionales vigentes para valores máximos de As en agua de consumo y en orina en niveles comparables con los establecidos en población laboralmente no expuesta. Esta propuesta metodológica es una alternativa para evaluar la exposición al As en muestras de agua y orina, sin necesidad de utilizar prolongados pre-tratamientos de muestra, de forma más rápida y económica.

Arsenic (As) is a natural contaminant that affects a large area of Argentina. Quantification of As in drinking water has been used to evaluate the source of exposure and As in urine to assess exposure to this toxic. This study aimed to optimize and validate a methodological technique for the quantification of As [As sum = inorganic As (AsI) + methylated species: monometilarsonic acid (MMA) and dimetilarsinic acid (DMA)], product of AsI metabolism by flow injection hydridegeneration-atomic absorption spectrometry (FI-GH-AAS), after derivatization with L-cysteine. The recovery of the studied species: AsI (AsIII and AsV), MMA and DMA was close to 100% in all cases. The limits of detection and quantitation were foundfor water and urine: 2 and 3 µg/L; 5 and 8 µg/L respectively and a linear working range from 5 to 75 µg/L, allowing quantify As in water close to international standards of maximum As values for drinking water and urine samples with levels comparables with those found in people non exposed ocupacionally . This methodology is a valid alternative for assessing exposure to As in water and urine samples without the need of prolonged pre-treatment sample, more quickly and inexpensively.

Daño al ADN asociado al contenido de arsénico urinario en una población de jóvenes expuesta al arsénico por el agua de bebida / DNA damage associated to urinary arsenic content in a children population exposed to arsenic by drinking water

El arsénico es un contaminante ampliamente distribuido en el mundo. En Argentina se estima que cerca de un millón y medio de personas están expuestas a sus efectos deletéreos por ingesta de agua con altos tenores de este metaloide. El presente trabajotuvo como objetivo establecer si existe correlación entre la exposición a arsénico inorgánico (AsI) a través del consumo de aguas y el nivel de daño al ADN. Muestras de orina y sangre fueron recolectadas de una población de la provincia de Santiago del Estero. Sobre éstas se evaluó el contenido de arsénico urinario (Asu) como marcador de exposición reciente y el daño producidoal ADN mediante el ensayo de electroforesis de células únicas (test del cometa) en sangre como índice de genotoxicidad. De la población total estudiada (n=65), el 41,54% fueron niños. El 57% de la población infantil presentó valores de Asu superiores al valor máximo referencial (hasta 40μgAs/g creatinina) en un rango comprendido entre 41,78 y 3918,10 μgAs/g creatinina. La evaluación genotóxica en sangre reveló que los niños expuestos a elevados niveles de arsénico presentaron un porcentajede células con alto daño al ADN significativamente mayor al compararlo con aquellos con Asu menor al valor de referencia (32,79% ± 3,32 vs 9,77% ± 6,59; p<0,001). A pesar del bajo número de muestras analizadas en este estudio preliminar, existe una buena correlación entre el contenido de arsénico urinario en la población general y el daño al ADN (r=0,6509; p=0,0117). Los resultados obtenidos muestran que la población estudiada expuesta a altos niveles de arsénico, representa un grupo de riesgo para el desarrollo de patologías relacionadas con este tóxico.

Arsenic is an environmental pollutantwidely distributed in the world. In Argentine about a million and a half of inhabitants are exposed to its deleterious effect by drinking water with high levels of this metalloid. In this work the correlation between the exposure to inorganic arsenic and thelevel of DNA damage in blood cells was assessed. Urine and blood samples were taken from a population of Santiago del Estero province. Urinary total arsenic (Asu) content (a recent exposure biomarker) and single cell gel electrophoresis (Comet assay) wereperformed. Children represented the 41.54% of the sampled population (n=65) and 57% of them had Asu levels between 41.78 and 3918.10 μgAs/g creatinine (reference value: less than 40μgAs/g creatinine). Comet assay showed that children with high levelof Asu presented a percentage of cells with high DNA damage increased respect to those with Asu below the reference value (32.79% ± 3.32 vs 9.77% ± 6.59, p< 0.001). Despite the small number of samples analyzed in this preliminary study, there is a clear tendency of correlation between total arsenic content in urine and DNA damage (r=0.6509, p=0.0117). The data obtained showed that the children population exposed to high levels of arsenic represent a group of risk for developing pathologies related with this toxic.

Determinación de arsénico total en orina en Chile: comparación de laboratorios / Measurement of total arsenic in urine in Chile: comparison of laboratories

Para evaluar la concordancia entre laboratorios en las mediciones de arsénico total en orina e identificar aquél cuyas determinaciones son de mayor precisión y exactitud, se diseñó un estudio experimental en el que muestras de orina con concentraciones conocidas de arsénico (6,5, 196 y 570 ug/l) fueron enviadas en 4 partidas separadas a 3 laboratorios nacionales diferentes. Los resultados confirman que existe una gran variedad intra- e interlaboratorios. En este estudio, en el que se controlaron todos los factores de error producto de la manipulación de la muestra de orina previo al ingreso a los laboratorios, se evidenció errores en la identificación de las muestras y falta de exactitud y precisión en los resultados. Sólo uno de los laboratorios mostró un comportamiento relativamente satisfactorio. Ante la evidencia presentada, se recomienda a los usuarios exigir a los laboratorios las pruebas necesarias para asegurar su trazabilidad, sus sistemas de aseguramiento de calidad y los resultados de los ejercicios de intercomparación en los que deberían participar regularmente. Una vez identificado el mejor laboratorio, el usuario debe generar un programa de aseguramiento de calidad propio basado en el envío de muestras con concentraciones conocidas del analito mezcladas con las muestras biológicas de trabajadores reales.

Un método para la evaluación de riesgos para la salud en zonas mineras / Health risk assessment of minig sites

Objetivo. En este trabajo se propone un esquema de tres fases para evaluar el riesgo en salud en las zonas mineras. La validación del esquema se efectuó en una zona de San Luis Potosí, México. Material y métodos. El monitoreo incluyó análisis de metales en suelo superficial, polvo residencial y agua de pozos. La biodisponibilidad se midió como el nivel de arsénico urinario en niños de las áreas contaminadas. La evaluación toxicológica consistió en análisis de la hepatotoxicidad (niveles de aspartato transaminasa) y neurotoxicidad (niveles de dopamina y de sus metabolitos) en ratas tratadas con residuos mineros. Resultados. Se encontró contaminación por arsénico y plomo en suelo y polvo. La biodisponibilidad fue positiva: 71 por ciento de los niños analizados tuvieron niveles urinarios de arsénico por arriba del valor normal. Los estudios de toxicidad mostraron daño hepático y alteraciones neuroquímicas en las ratas tratadas con el residuo. Conclusiones. El método fue útil para demostrar el riesgo en salud y para que las autoridades decidieran instrumentar un programa de restauración en la zona

Exposición ocupacional al arsénico en la industria metalurgica del cobre / Occupational exposure to arsenic in the copper metallurgical industry

Para establecer el estado de salud actual y verificar el impacto de los contaminantes plomo y arsénico en los indicadores biológicos plomo hemático y arsénico urinario estudiamos a 166 trabajadores expuestos directamente al plomo, tiróxido de arsénico y otros contaminantes en los tostadores de cobre y arsénico de la fundición primaria de cobre de la Oraya, Perú. Concomitantemente se determinan las concentraciones ambientales de los contaminantes y se examina clínica y laboratorialmente a toda la población expuesta. Dosamos plomo hemático y arsénico urinario por el método de absorción atómica y de la ditizona, respectivamente. Las muestras ambientales se toman por el método de succión húmeda y por absorción atómica se cuantifican los contaminantes. Los hallazgos demuestran que los trabajadores de los tostadores de cobre de la Fundición de La Oroya presentan estigmas de exposición aguda y crónica al arsénico y al plomo. Las medias de plomo hemático y arsénico urinario se hallan alrededor de lo permisible para la ley peruana, pero cercanos a los márgenes superiores de los límites de tolerancia biológica internacionales. Los resultados se cotejan con los de un estudio similar realizado en 1963 a la misma sección. Luego de las comparaciones estadística se concluye que el impacto toxicológico en los trabajadores de tostadores de cobre sigue siendo fuerte, principalmente en lo referido al plomo.