Resumo Os poluentes ambientais podem frequentemente alterar os componentes genéticos das populações naturais. Neste estudo, metais pesados e diversidade genética em caramujos terrestres (Achatina achatina) de três populações do sudoeste da Nigéria foram investigados, usando a tecnologia de espectrometria de absorção atômica e sequenciamento de DNA, respectivamente. A análise dos metais revelou que os caramujos acumularam chumbo (Pb) e níquel (Ni) em altas concentrações em dois dos três estados, enquanto o cádmio (Cd) foi o menos detectado. A edição e o alinhamento das sequências de todos os acessos de caramujos geraram uma faixa de 384pb a 419pb. A análise de variância molecular (AMOVA) em todos os 18 acessos foi baixa em apenas 16%. A cobertura da consulta (QC) variou entre 96% e 100%, com 14 (77,8%) dos 18 acessos apresentando 100% de identidade. A comparação pareada dos acessos estudados também mostrou alta similaridade genética. O método de grupo de pares não ponderados com média aritmética (UPGMA) gerou dois clusters principais. O cluster I era único e contém uma amostra (AaOy06), enquanto o outro cluster está intimamente relacionado e pode ser subdividido em subclusters. O índice de similaridade entre os clusters é 0,5357. A grande semelhança entre os acessos pode ser devido à proximidade geográfica dos três estados. A singularidade do acesso AaOy06 em comparação com outros acessos pode ser devido à influência negativa de metais pesados, particularmente chumbo. A determinação das relações evolutivas entre as populações de caramujos pode ser útil para os esforços de reprodução da espécie na Nigéria.

Abstract Environmental pollutants may often alter the genetic components of natural populations. In this study, heavy metals and genetic diversity in land snail (Achatina achatina) from three populations of south-western Nigeria were investigated, using the Atomic Absorption Spectrometry and DNA Sequencing technology respectively. Metal analysis revealed that the snails accumulated lead (Pb) and nickel (Ni) in high concentrations in two of the three states, while cadmium (Cd) was the least detected. Editing and alignment of the sequences of all snail accessions generated a range of 384bp to 419 bp. Analysis of Molecular Variance (AMOVA) in all 18 accessions was low at only 16%. The query coverage (QC) ranged between 96% and 100%, with 14 (77.8%) of the 18 accessions showing 100% identity. Pairwise comparison of the accessions studied also showed a high genetic similarity. The unweighted pair group method with arithmetic mean (UPGMA) generated two main clusters. Cluster I was unique and contain one sample (AaOy06) while the other cluster are very closely related and can be further sub-divided into sub-clusters. The similarity index of between the clusters is 0.5357. The close similarity among the accessions may be due to the geographical proximity of the three states. The uniqueness of accession AaOy06 in comparison to other accessions might be due to the negative influence of heavy metal, particularly lead. The determination of evolutionary relationships among snail populations may be useful towards the breeding efforts of the species in Nigeria.

Resumo O sistema enzimático antioxidante é um importante mecanismo de defesa para lidar com Espécies Reativas de Oxigênio (EROs) produzidas por causa da exposição a metais pesados. No presente estudo, o chumbo (Pb), o cromo (Cr), o arsênio (As), o cádmio (Cd), o níquel (Ni) em água e a atividade antioxidante da superóxido dismutase (SOD), catalase (CAT) e peroxidase (POD) foram investigados em três espécies (Metrocoris communis, Limnogonus fossarum fossarum e Aquarius adelaidis) de gafanhotos coletados no triângulo industrial de Punjab, Paquistão. Os resultados do presente estudo revelaram que Pb, Cr, As, Cd e Ni estavam de acordo com a quantidade permitida pela OMS. A atividade antioxidante de SOD, CAT e POD foi significativamente diferente entre as espécies diante do estresse oxidativo, mas encontrou a maior atividade de determinação de parâmetros em A. adelaidis. Este é um dos estudos pioneiros no Paquistão que relatam o papel dos water striders como bioindicador de metais pesados presentes na água por meio de variações de enzimas antioxidantes. Os resultados atuais indicaram que o nível variante de atividades de enzimas antioxidantes em diferentes espécies de water striders refletiu a poluição por metais pesados no triângulo industrial de Punjab, Paquistão, e será uma ferramenta ecotoxicológica útil para avaliar os efeitos prejudiciais de poluentes de metais pesados em organismos aquáticos .

Abstract The antioxidant enzyme system is an important defense mechanism to cope with Reactive Oxygen Species (ROS) produced due to exposure to heavy metals. In the present study lead (Pb), chromium (Cr), arsenic (As), cadmium (Cd) and nickel (Ni) in water and the antioxidant activity of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) was investigated in three species (Metrocoris communis, Limnogonus fossarum fossarum, and Aquarius adelaidis) of water striders collected from the industrial triangle of Punjab, Pakistan. The results of present study revealed that Pb, Cr, As, Cd and Ni were according to the permissible amount of WHO. The antioxidant activity of SOD, CAT and POD was found significantly different among species against oxidative stress, but found the highest activity of determining parameters in A. adelaidis. This is one of the pioneer studies in Pakistan reporting the role of water striders as a bioindicator of heavy metals present in the water through antioxidants enzyme variations. The current results supported that variant level of antioxidant enzyme activities in different species of water strider were reflective of heavy metal pollution in the Industrial triangle of Punjab, Pakistan and will be a useful ecotoxicological tools to evaluate the detrimental effects of heavy metal pollutants in aquatic organisms.

Resumo O peixe é considerado o mais adequado para indicação de toxicidade na água. Assim, o objetivo do presente estudo foi determinar as concentrações de alguns metais (Na, K, Ca, Mg, Fe, Cd, Pb e Zn) em relação ao tamanho corporal e fator de condição em Scomberoides commersonnianus. Foi coletado um total de 73 amostras de peixes marinhos, S. commersonnianus, com tamanhos que variaram de 93,4 a 1.180 g de peso corporal e comprimento total de 20,5 a 56,9 cm, aleatoriamente do Mar Arábico de Karachi, Paquistão, para exame de composição elementar. A concentração de Ca foi máxima, enquanto a de Cd foi mínima em S. commersonnianus. As concentrações de Zn mostraram-se altamente significativas negativas (P < 0,001), enquanto Na e Ca apresentaram forte correlação positiva com o tamanho dos peixes. As correlações de Pb, K e Mg foram menos significativas (P < 0,05) com o peso úmido e o comprimento total de S. commersonnianus. Já o Fe e o Cd permaneceram pouco correlacionados (P > 0,05) com o tamanho dos peixes. O fator de condição apresentou correlação altamente significativa (P < 0,001) com todos os metais estudados, exceto Cd e Pb, que foram encontrados correlacionados insignificantemente (P > 0,05) com o fator de condição de S. commersonnianus.

Abstract Fish is thought to be the most appropriate for indication of toxicity in water. So, purpose of present study was to determine the concentrations of few metals (Na, K, Ca, Mg, Fe, Cd, Pb and Zn) in relation to the body size and condition factor in Scomberoides commersonnianus. A total of 73 samples of marine fish, S. commersonnianus with various sizes that ranged from 93.4-1180 g of body weight and total length 20.5-56.9cm were randomly collected from the Arabian Sea of Karachi Pakistan, for examination of elemental composition. The concentration of Calcium found maximum while Cadmium found minimum in S. commersonnianus. Concentrations of Zn showed highly significant (P<0.001) negative, while Na and Ca exhibited strong positive correlation with the fish size. Correlations of Pb, K and Mg were found least significant (P<0.05) with the wet weight and total length of S. commersonnianus. Whereas, Fe and Cd were remained insignificantly correlated (P>0.05) with the fish size. Condition factor showed highly significant correlation (P<0.001) with all studied metals except cadmium and lead which were found insignificantly correlated (P>0.05) with condition factor of S. commersonnianus.

Abstract Sorption and desorption tests were carried out for competitive and non-competitive systems with isotherms to verify the presence of Cd and Pb in soils. The soils investigated were: (i) with natural content of organic matter and (ii) with residual content of organic matter. Hydrated nitrate salts of Cd and Pb diluted in 0.01 M calcium nitrate solution in six concentrations were used for the Cd solutions and, for the solutions of Pb, five concentrations. For multi-element solutions, mixtures of the simple Cd and Pb solutions in a 1:1 ratio were used. The results of the first stage tests (i) showed good adjustments of the experimental data to the isotherms of Langmuir, Freundlich and Linear, which did not occur for the tests in stage (ii). According to the tests (i), the organic matter was the soil attribute of dominant influence in the sorting mechanisms. The parameters Qo and Kd were adequate to evaluate the adsorption of the studied metals, especially Cd. In step (ii), there was a significant increase in metal retention, especially for element Pb in the samples of Haplic Cambisol (AM) and Red-Yellow Latosol1 (RO), justified by the combined action of (1) increasing the surface area of the mineral fraction, previously covered by organic matter; and (2) increase in soil pH. The Cd element was more bioavailable in relation to the Pb. This was confirmed by the high desorption values observed for Cd. The samples of Haplic Cambisol and Red-Yellow Latosol demonstrated greater capacity to retain Cd and Pb.

Resumen La contaminación del suelo superficial de las tres ciudades industriales de Urmia, a 9 km al noreste de esta ciudad, es el tema de este artículo. Para ello, se tomaron muestras en 9 puntos y se analizaron metales pesados como hierro, manganeso, cadmio, cobre, zinc y plomo para calcular los indicadores del índice de geoacumulación y los factores de contaminación de estos metales pesados. Para calcular estos factores, debe calcularse la concentración de fondo de cada elemento. Se utilizaron 59 muestras para cada elemento en las zonas prístinas de la llanura de Urmia mediante el método de absorción atómica. Los resultados de la investigación presentada muestran que el suelo de la región está contaminado con metales pesados, por lo que la cantidad de contaminación para los metales pesados manganeso y cadmio es exigua, y para los metales pesados hierro y cobre, están en el rango medio y para los metales pesados zinc y plomo, están en el rango alto. La concentración de contaminación en los alrededores de la ciudad de la fase de expansión y de la fase 2 es mayor que en la ciudad de la fase 1, lo que parece deberse a la actividad de la industria alimentaria en la ciudad de la fase 1 y a la actividad de las industrias electrónica, de pinturas y metalúrgica en la fase de expansión y en la fase 2. Parece que las elevadas cantidades de metales pesados de plomo y zinc en los suelos de los alrededores de las ciudades industriales de Urmia se deben a las actividades de unidades de producción como la industria electrónica, la industria cerámica, la industria metalúrgica, la industria de pinturas y la producción de baterías. Las industrias mencionadas vierten sus aguas residuales industriales en los alrededores de las ciudades y provocan la contaminación del suelo. La figura 7 muestra el vertido de aguas residuales industriales de la ciudad en fase de expansión a los alrededores. Parece que la creación de una planta de tratamiento de aguas residuales para las unidades contaminantes y el aumento de la capacidad de la planta de tratamiento existente en la ciudad industrial son importantes para reducir la contaminación.

Abstract The surface soil pollution of the three industrial towns of Urmia, 9 km northeast of this city, is the subject of this article. For this purpose, samples were taken from 9 points, and heavy metals such as iron, manganese, cadmium, copper, zinc, and lead has been analyzed to calculate the indicators of Geoaccumulation Index and pollution factors for these heavy metals. The background element concentration should be calculated for each element to calculate these factors. 59 samples for each element were used in the pristine areas of Urmia Plain by atomic absorption method. The presented research results show that the soil of the region is contaminated with heavy metals, so the amount of contamination for heavy metals manganese and cadmium is meager, and for the heavy metals iron and copper, they are in the middle range and for the heavy metals zinc and lead, they are in the high range. The pollution concentration around the town of expansion phase and phase 2 is more than the town of phase 1, which seems to be the cause of the food industry activity in the town of phase 1 and the activity of electronics, paint and metal industries in the expansion phase and phase 2. It seems that the high amounts of lead and zinc heavy metals in the soils around the industrial towns of Urmia are due to the activities of production units such as electronic industry, ceramics industry, metal industry, paint industry and battery production. The aforementioned industries dump their industrial waste water into the surroundings of the towns and cause soil pollution. Figure 7 shows the discharge of industrial wastewater from the expansion phase town to surrounding area. It seems that the creation of a wastewater treatment plant for polluting units and increasing the capacity of the existing treatment plant in the industrial town is important in reducing pollution.

RESUMO Introdução: A poluição decorrente da industrialização tem levado ao aumento da concentração de metais em diversos ambientes e à sua incorporação em matérias-primas e produtos acabados, o que tem impacto direto na saúde humana. Objetivo: Quantificar metais na matéria-prima utilizada na fabricação do comprimido mastigável LECISAN® e no comprimido, estabelecer teores de referência de: alumínio, cálcio, cádmio, cromo, cobre, ferro, magnésio, chumbo, silício, vanádio e zinco. Método: Foi utilizada espectrometria de emissão óptica atômica com plasma indutivamente acoplado (ICP OES) e os intervalos de confiança para a média dos valores quantificados foram estabelecidos por meio de métodos estatísticos com probabilidade de 95%. Resultados: Existem diferenças significativas entre as duas formas de apresentação quanto à quantidade de todos os metais, exceto alumínio (p<0,05). Os coeficientes de variação foram baixos, o cromo obteve valor próximo a 10% na matéria-prima e o chumbo foi alto (17,44%). Os valores estão dentro da faixa informada como permitida segundo as normas cubanas (NC 493:2012) exceto para chumbo e cobre. Foram observadas concentrações mais elevadas desses elementos com efeitos favoráveis à saúde. Conclusões: Os resultados encontrados devem ser considerados referências para a avaliação do impacto que o regime diário de administração do suplemento nutricional LECISAN® teria na saúde e a análise dos fatores relacionados à presença de metais em subprodutos do refino do óleo de soja para pesquisas futuras.

RESUMEN Introducción: La contaminación resultante de la industrialización ha propiciado el aumento de la concentración de metales en diversos ambientes y su incorporación a materias primas y productos terminados, lo que repercute directamente en la salud humana. Objetivo: Cuantificar metales en la materia prima empleada en la fabricación de la tableta masticable LECISAN® y en la tableta, para establecer niveles de referencia de: aluminio, calcio, cadmio, cromo, cobre, hierro, magnesio, plomo, silicio, vanadio y zinc. Método: Se utilizó la espectrometría atómica de emisión óptica con plasma inductivamente acoplado (ICP OES) y se establecieron mediante métodos estadísticos los intervalos de confianza para la media de los valorescuantificados con una probabilidad del 95%. Resultados: Existen diferencias significativas entre las dos formas de presentación en cuanto a la cantidad de todos los metales, excepto aluminio (p<0,05). Los coeficientes de variación fueron bajos, el cromo obtuvo un valor cercano al 10% en la materia prima y el plomo resultó elevado (17,44 %). Los valores se encuentran dentro del rango reportado como permisibles según norma cubana (NC 493:2012) excepto para plomo y cobre. Se observaron mayores concentraciones de aquellos elementos con efectos favorables para la salud. Conclusiones: Los resultados encontrados deben ser considerados como referenciales para la evaluación del impacto que sobre la salud tendría el régimen de administración diaria del suplemento nutricionalLECISAN® yel análisis de factores relacionados con la presencia de metales en subproductos del refinado del aceite de soya para futura investigaciones.

ABSTRACT Introduction: The pollution resulting from industrialization has led to an increase in the concentration of metals in various environments and their incorporation into raw materials and finished products, which has a direct impact on human health. Objective: To quantify metals in the raw material used in the manufacture of the LECISAN® chewable tablet and in the tablet, to establish reference levels of: aluminum, calcium, cadmium, chromium, copper, iron, magnesium, lead, silicon, vanadium and zinc. Method: Atomic optical emission spectrometry with inductively coupled plasma (ICP OES) was used and confidence intervals for the mean of the quantified values were established using statistical methods with a probability of 95%. Results: There are significant differences between the two presentation forms in terms of the amount of all metals, except aluminum (p<0.05). The variation coefficients were low, chromium obtained a value close to 10% in the raw material and lead was high (17.44%). The values are within the range reported as permissible according to Cuban standards (NC 493:2012) except for lead and copper. Higher concentrations of those elements with favorable health effects were observed. Conclusions: The results found should be considered as references for the evaluation of the impact that the daily administration regimen of the LECISAN® nutritional supplement would have on health and the analysis of factors related to the presence of metals in by-products of soybean oil refining for future research.

ABSTRACT Mining environmental liabilities (MEL) are metal-intensive wastes that have the potential to contaminate the surrounding soil, adversely affecting water and air quality, degrading ecosystems, and causing toxic effects on human health. This study used electrochemical treatment as a remediation technique to decontaminate soil affected by MEL. Through a mixed factorial design, the effects of the improvement solutions, acetic acid, and nitric acid, and three distances from the soil with respect to the anode, on the residual concentration and one-dimensional spatial distribution of Pb, Cd, and Zn were investigated. The tests were carried out in triplicate, in acrylic cells, for five days, submitted to 30 V of power, and with nitric acid as cathode fluid. The results showed that nitric acid reduces 4.0, 11.5, and 11.3 times the content of Pb, Cd, and Zn compared to acetic acid, that is, the highest removal percentages of Pb, Zn, and Cd were 40, 34, and 23 %, respectively, when using nitric acid. Moreover, the one-dimensional spatial distribution of metals in the post-treatment soil was not an increasing concentration gradient from the anode region to the cathodic region, but was rather a homogeneous trend. Therefore, using nitric acid as the enhancement fluid confirmed the viability of the electrochemical treatment, although it should be enhanced under other experimental conditions to achieve higher remediation rates.

RESUMEN Los pasivos ambientales mineros (PAM) son residuos con alta carga de metales que tienen el potencial de contaminar el suelo circundante, afectar negativamente la calidad del agua y aire, degradar los ecosistemas y provocar efectos tóxicos en la salud humana. Este estudio utilizó el tratamiento electroquímico como técnica de remediación para descontaminar un suelo afectado por PAM. A través de un diseño factorial mixto se investigó los efectos de las soluciones de mejora, ácido acético y ácido nítrico, y tres distancias del suelo respecto al ánodo, sobre la concentración residual y distribución espacial unidimensional de Pb, Cd y Zn. Los ensayos se realizaron por triplicado, en celdas de acrílico, durante cinco días, sometidos a 30 V de potencia y con ácido nítrico como fluido catódico. Los resultados demostraron que el ácido nítrico reduce 4.0, 11.5 y 11.3 veces el contenido de Pb, Cd y Zn en comparación con el ácido acético, es decir, que los mayores porcentajes de remoción del Pb, Zn y Cd fueron 40, 34 y 23 % respectivamente, al emplear ácido nítrico. Asimismo, la distribución espacial unidimensional de los metales en el suelo después del tratamiento, no fue un gradiente de concentración creciente desde la región anódica hacia la región catódica, sino una tendencia homogénea. Por tanto, emplear ácido nítrico como fluido de mejora confirmó la viabilidad del tratamiento electroquímico, aunque se debería potenciar en otras condiciones experimentales para alcanzar mayores tasas de remediación.

Adsorption is one of the most easy-to-operate, less costly, efficient and, most importantly, environmentally friendly methods of removing toxic metals from aqueous environments. We used spent Impra Green Tea Ginseng Flavoured to recover mercury (Hg²+), lead (Pb²+) and cadmium (Cd²+) in binary and ternary systems from greywater. We undertook this study in binary and ternary systems at adsorbent dosages with a corresponding 100 mL varied initial metal concentrations of the greywater. The adsorption efficiency at varied concentrations and dosages in the binary systems by the spent tea waste ranged from 38.5% to 100% for lead, 11.50% to 100% for cadmium and was 100% for mercury. In the ternary system, the adsorption efficiency of toxic metals ranged from 28.91% to 72.85% for cadmium and was 100% for mercury and lead. The maximum adsorption capacity (Qe) for toxic metals in the binary system ranged from 38.46 to 81.97 mg/g for Pb²+ and 12.64 to 56.82 mg/g for Cd²+. The Langmuir adsorption isotherm model was the best fit for the adsorption of toxic metals by Impra Green Tea Ginseng Flavoured. The pH under which the experiments were conducted showed very high removal efficiency for lead and mercury but lower removal efficiencies for cadmium. Spent Impra Green Tea Ginseng Flavoured can be used as an effective and low-cost adsorbent of toxic metals from greywater or wastewater. Based on our findings, further studies should be conducted to determine the effects of varying the contact time, temperature and elevated metal concentrations in the greywater or other wastewater. SIGNIFICANCE: • This study provides useful information on how spent Impra Green Tea Ginseng Flavoured can be used as an effective and low-cost adsorbent of toxic metals from greywater or wastewater.

Resumen Con el fin de investigar el efecto de cuatro biosólidos de las industrias láctea, maltera, jabonera y papelera sobre el crecimiento y producción de biomasa de plántulas de Vicia faba L., se realizaron mezclas de biosólido:suelo en proporciones 20:80, 40:60 y 60:40. Se realizaron análisis fisicoquímicos y microbiológicos a cada biosólido y las mezclas. Los biosólidos mostraron diferencias en la presencia (NMP) de coliformes fecales de 3 a 1 100 Salmonella sp., de 2 a 3 y de 0 a 16 huevos de helmintos por g de sólidos totales. La concentración (mg kg-1) de metales pesados en cobre fue de 0.7 a 1.9, cromo de 0.8 a 2.4, cadmio de 0 a 0.6, zinc de 4.3 a 8.6, níquel 1.2 a 3.8 y plomo 1.3 a 5.7, sin arsénico y mercurio. Los contaminantes fueron inferiores a los límites permisibles según la SEMARNAT (2002), además, entre los biosólidos el pH varió de 7 a 9.8 y la materia orgánica (MO) de 0.3 a 6.2%. Los biosólidos de la industria láctea y malta incorporados al suelo modificaron el pH de 8.1 a 7.4, incrementaron la MO de 1.2 a 3.5%, el nitrógeno total de 7 a 35 mg kg-1 y el fósforo disponible de 5 a 25 mg kg-1. A 30 días después de la siembra en invernadero, las plántulas de V. faba que crecieron en suelo con el biosólido de la industria láctea en la mayor proporción incrementaron la producción de biomasa en 1 145% y la longitud en 342%.

Abstract In order to investigate the effect of four biosolids from the dairy, malt, soap and paper industries on the growth and production of biomass of Vicia faba L. seedlings, biosolid:soil mixtures were made in ratios 20:80, 40:60 and 60:40. Physicochemical and microbiological analyses were performed on each biosolid and mixtures. Biosolids showed differences in the presence (MPN) of fecal coliforms from 3 to 1 100, Salmonella sp., from 2 to 3 and from 0 to 16 helminth eggs per g of total solids. The concentration (mg kg-1) of heavy metals in copper was from 0.7 to 1.9, chromium from 0.8 to 2.4, cadmium from 0 to 0.6, zinc from 4.3 to 8.6, nickel from 1.2 to 3.8 and lead from 1.3 to 5.7, without arsenic and mercury. The contaminants were below the permissible limits according to SEMARNAT (2002), in addition, among biosolids the pH varied from 7 to 9.8 and organic material (OM) from 0.3 to 6.2%. Biosolids from the dairy and malt industries incorporated into the soil modified the pH from 8.1 to 7.4, increased OM from 1.2 to 3.5%, the total nitrogen from 7 to 35 mg kg-1 and the available phosphorus from 5 to 25 mg kg-1. At 30 days after sowing in the greenhouse, V. faba seedlings grown in soil with the biosolid from the dairy industry in the highest ratio increased biomass production by 1 145% and length by 342%.

A new approach involving square wave anodic stripping voltammetry was developed to simultaneously determine cadmium and lead and, in the same cell, sequentially copper, in biodiesel after extraction induced by microemulsion breaking. The composition of the water-in-oil microemulsion involved 10.50 mL biodiesel, 4.20 mL n-propanol and 0.30 mL of the 6.0 mol L 1 HNO3 solution. The extraction was carried out by adding 1.10 mL ultrapure water resulting in two well separated phases: an upper organic phase, and a lower aqueous phase containing the analytes. The apparatus comprised a portable potentiostat and a cell with an in situ plated mercury film glassy carbon electrode as working electrode. The limits of detection for Cd, Pb and Cu were 0.33, 0.48 and 0.66 µg L 1, respectively. The accuracy of the method was evaluated by recovery assays of spiked samples and by analyzing a standard reference material.

Resumen Antecedentes: En México es exigua la evidencia sobre la exposición prenatal a metales. Objetivo: Estimar la concentración de arsénico, cadmio, manganeso y plomo en sangre de cordón umbilical (SCU), y su asociación con las concentraciones en sangre materna durante el embarazo y parto. Material y métodos: Se analizó la concentración de los metales en sangre materna durante el embarazo (n = 901), parto (n = 732) y en la SCU (n = 512) de participantes de la cohorte PROGRESS, residentes en la Ciudad de México. Se estimó la asociación entre la concentración en SCU y los biomarcadores maternos mediante modelos lineales generalizados, ajustados por covariables relevantes. Resultados: La media (μg/L) de plomo, arsénico y manganeso en SCU fue 27.14 (25.28-29.14), 0.77 (0.71-0.84) y 42.60 (40.45-44.83), respectivamente. El valor del cadmio no se pudo estimar porque 86.2 % de las mediciones fueron inferiores al límite de detección. Las concentraciones de plomo y manganeso en SCU se asociaron significativamente a los biomarcadores maternos durante el embarazo y el parto; solo se observó asociación con arsénico en el parto. Conclusiones: La exposición prenatal a metales tóxicos en periodos sensibles de la organogénesis evidencia un problema de salud pública desatendido. Se requiere un biomonitoreo poblacional y establecer regulación dirigida a proveer atención a población vulnerable.

Abstract Background: In Mexico, there is a paucity of evidence on the magnitude of prenatal exposure to metals. Objective: To estimate the concentration of arsenic, cadmium, manganese and lead in umbilical cord blood (UCB) and its association with maternal blood concentrations during pregnancy and delivery. Material and methods: Metal concentration in maternal blood was analyzed during pregnancy (n = 901), delivery (n = 732) and in UCB (n = 512) from participants of the PROGRESS cohort residing in Mexico City. The association between concentrations in UCB and maternal biomarkers was analyzed using generalized linear models, adjusted for relevant covariates. Results: Mean concentrations (μg/L) of lead, arsenic and manganese in UCB were 27.14 (25.28-29.14), 0.77 (0.71-0.84) and 42.60 (40.45-44.83), respectively. Cadmium concentration could not be estimated because 86.2% of measurements were below the detection limit. Lead and manganese concentrations in UCB were significantly associated with maternal biomarkers during pregnancy and delivery; at delivery, association was only observed with arsenic. Conclusions: Prenatal exposure to toxic metals in sensitive periods of organogenesis shows a neglected public health problem. Biomonitoring of the population and establishment of regulations aimed at providing care to vulnerable populations is required.

Resumen Introducción. El consumo de metales pesados puede provocar problemas de salud en los animales. Objetivo. Determinar la concentración de cadmio, mercurio, plomo y arsénico en 34 alimentos balanceados importados y comercializados en Costa Rica para perros, gatos, conejos, hámsteres, tortugas y peces ornamentales. Materiales y métodos. Se cuantificó el contenido de arsénico (As), cadmio (Cd), mercurio (Hg) y plomo (Pb) en alimentos balanceados importados para seis animales de compañía, durante los meses de mayo a octubre del año 2018. De forma aleatoria, se visitaron expendios autorizados de alimentos balanceados y se compraron diez empaques de alimento para perros y gatos, cinco para peces ornamentales, cuatro para tortugas, tres para hámsteres y dos para conejos. Las muestras fueron analizadas en el Centro de Investigación en Nutrición Animal de la Universidad de Costa Rica mediante espectrofotometría de absorción atómica con atomizador de tubo de grafito (As, Cd, Pb) y de celda de cuarzo (Hg). Resultados. Las concentraciones obtenidas en alimentos para perros y gatos, adultos y cachorros, conejos, hámsteres, peces ornamentales y tortugas, fueron para As de 0,009, 0,013, 0,003, no detectable (ND), ND, 0,036 y 0,113 ppm, respectivamente; para Cd de ND, 0,021, 0,022, 0,031, 0,010, 0,037, 0,139 y 0,043 ppm, respectivamente; para Hg de 0,101, 0,078, 0,045, 0,040, 0,031, 0,045, 0,032 y 0,032 ppm, respectivamente, y para Pb de 0,381, 0,885, 0,573, 0,740, 0,446, 0,732, 0,763 y 0,841 ppm, respectivamente. Conclusión. Los contenidos de metales pesados determinados en alimentos para mascotas, no superaron los valores máximos permitidos para su comercialización. Este trabajo incrementa la información disponible en temas de inocuidad de alimentos balanceados en peces ornamentales, hámsteres, tortugas y conejos; promueve estrategias de monitoreo continuo de estos y la comprensión del potencial real de acumulación en los animales y sus efectos en el bienestar de los mismos.

Abstract Introduction. The intake of heavy metals can cause health problems in animals. Objective. To determine the concentration of cadmium, mercury, lead, and arsenic in 34 imported balanced foods marketed in Costa Rica for dogs, cats, rabbits, hamsters, turtles, and ornamental fish. Materials and methods. The content of arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) in imported balanced foods for six pets was quantified during the months of May to October 2018. On a random basis, authorized feed stores were visited to purchased ten packages of dog and cat food, five for ornamental fish, four for turtles, three for hamsters, and two for rabbits. The samples were analyzed at the Animal Nutrition Research Center of the Universidad de Costa Rica using atomic absorption spectrophotometry with graphite tube atomizer (As, Cd, Pb) and quartz cells (Hg). Results. The concentrations obtained in the food for dogs and cats, adults and puppies, rabbits, hamsters, ornamental fish, and turtles were for As 0.009, 0.013, 0.003, non-detectable (ND), ND, 0.036, and 0.113 ppm, respectively; for Cd ND, 0.021, 0.022, 0.031, 0.010, 0.037, 0.139, and 0.043 ppm, respectively; for Hg 0.101, 0.078, 0.045, 0.040, 0.031, 0.045, 0.032, and 0.032 ppm, respectively, and for Pb of 0.381, 0.885, 0.573, 0.740, 0.446, 0.732, 0.763, and 0.841 ppm, respectively. Conclusions. The contents of heavy metals in pet foods did not exceed the maximum values allowed for their commercialization. This work increases the information available on the safety of food for ornamental fish, hamsters, turtles, and rabbits, also promotes continuous monitoring strategies, and the understanding of the real potential for accumulation in animals, and its effects on their welfare.

Resumen En el área de la salud es necesario conocer el rango de referencia de los elementos traza en hígado humano sano, dato no informado, ya que éstos se relacionan con frecuencia con enfermedades metabólicas que afectan al hígado. La mayoría de los trabajos publicados describen valores de diversas regiones del mundo a partir de tejido hepático sano post mortem, o de individuos vivos con enfermedad hepática. El objetivo de este trabajo fue determinar el rango de concentración para el hierro (Fe), cobre (Cu), cadmio (Cd) y plomo (Pb) en el hígado sano de seres humanos vivos del noroeste argentino mediante espectrometría de absorción atómica. Las muestras de tejido hepático fueron digeridas mediante un sistema de microondas utilizando un programa previamente optimizado. La cuantificación se realizó por espectrometría de absorción atómica con la técnica de atomización por llama para el Fe, y la de vaporización electrotérmica para Cu, Cd y Pb. Las respectivas técnicas fueron validadas. Los rangos de concentración obtenidos, en μg/g de peso seco, fueron: Fe (322-1349), Cu (6,66-34,8), Cd (0,221-6,18) y Pb (0,340-23,8). Los valores registrados en este trabajo difieren de los publicados por diversos autores, probablemente por las condiciones del tejido hepático, post mortem en algunos casos, o de individuos vivos con hígado enfermo en otros. Estos resultados podrían constituir un aporte para establecer los rangos de referencia de elementos trazas esenciales y no esenciales en tejido hepático para la región estudiada.

Resumo Na área da saúde, é necessário conhecer a gama de referência dos elementos vestigiais no fígado humano saudável, que não foi relatada, pois eles estão frequentemente relacionados com doenças metabólicas que afetam o fígado. A maioria dos trabalhos publicados descreve valores de várias regiões do mundo a partir de tecido hepático saudável post mortem, ou de indivíduos vivos com doença hepática. O objetivo deste trabalho foi determinar a faixa de concentração de ferro (Fe), cobre (Cu), cádmio (Cd) e chumbo (Pb) no fígado saudável de humanos vivos do noroeste da Argentina por espectrometria de absorção atômica. As amostras de tecido hepático foram digeridas em um sistema de microondas usando um programa previamente otimizado. A quantificação foi realizada por espectrometria de absorção atômica usando a técnica de atomização por chama para Fe, e vaporização eletrotérmica para Cu, Cd e Pb. As respectivas técnicas foram validadas. As faixas de concentração obtidas, em μg/g de peso seco, foram: Fe (322-1349), Cu (6,66-34,8), Cd (0,221-6,18) e Pb (0,340-23,8). Os valores registrados neste trabalho diferem daqueles publicados por vários autores, provavelmente devido às condições do tecido hepático, post mortem em alguns casos ou de indivíduos vivos com fígado doente em outros. Estes resultados poderiam ser uma contribuição para estabelecer faixas de referência para elementos vestigiais essenciais e não essenciais em tecido hepático para a região estudada.

Abstract In the health area it is necessary to know the reference range of trace elements of a healthy human liver, which is not reported, since these elements are frequently related to metabolic diseases affecting the liver. Most of the published work describes values from different regions of the world from healthy liver tissue post mortem, or from living individuals with liver disease. The objective of this study was to determine the concentration range for iron (Fe), copper (Cu), cadmium (Cd) and lead (Pb) in the healthy liver of living humans from northwestern Argentina by atomic absorption spectrometry. Liver tissue samples were digested by a microwave system using a previously optimised program. Quantification was performed by atomic absorption spectrometry using the flame atomisation technique for Fe, and electrothermal vaporisation for Cu, Cd and Pb. The respective techniques were validated. The concentration ranges obtained, in μg/g dry weight, were: Fe (322–1349), Cu (6.66-34.8), Cd (0.221-6.18), and Pb (0.340-23.8). The values recorded in this work differ from those published by various authors, probably due to the conditions of the liver tissue, post mortem in some cases, or from living individuals with diseased liver in others. These results could be a contribution to establish reference ranges of essential and non-essential trace elements in liver tissue for the region studied.

ABSTRACT OBJECTIVE To compare the incidence of covid-19 symptoms between informal home-based workers and a control group and to assess the association of these cases with blood elements concentrations and other relevant risk factors for Sars-Cov-2 infection. METHODS Welders chemically exposed to potentially toxic elements (PTEs) (n = 26) and control participants (n = 25) answered questionnaires on adherence to social distancing and signs and symptoms of the disease for five months during the covid-19 pandemic. After follow-up, covid-19 serology tests were performed on a subsample of 12 chemically exposed workers and 20 control participants. Before the pandemic, PTE concentrations in blood (As, Mn, Ni, Cd, Hg, Sb, Sn, Cu, Zn, and Pb) were measured by ICP-MS. RESULTS The chemically exposed group had higher lead and cadmium levels in blood (p < 0.01). The control group presented lower adherence to social distancing (p = 0.016). Although not significant, welders had a 74% greater chance of having at least one covid-19 symptom compared with control participants, but their adherence to social distancing decreased this chance by 20%. The use of taxis for transportation was a risk factor significantly associated with covid-19 symptoms. CONCLUSION The lower adherence to social distancing among the control group greatly influences the development of covid-19. The literature lacks data linking exposure to PTEs and Sars-Cov-2 infection and/or severity. In this study, despite chemical exposure, working from home may have protected welders against covid-19, considering that they maintained greater social distancing than control participants.

RESUMO Para investigar o papel do esterco de vaca na recuperação do solo e bioassimilação, juntamente com a bioacumulação de metais pesados em minhocas (P. posthuma) (N = 900), minhocas foram usadas e grupos de tratamento de mistura CD-solo de diferentes proporções de esterco de vaca foram projetados. Doses não letais de acetato de chumbo e cloreto de cádmio foram adicionadas aos grupos de tratamento. P. posthuma maduros foram liberados em cada vaso experimental, mantendo as condições favoráveis. Foram avaliados o pH, carbono, nitrogênio, fósforo, cátions trocáveis e nível de metais pesados de cada mistura. Os resultados indicaram que a bioassimilação de Pb e Cd por P. posthuma foi significativamente (P ˂ 0,01) maior em diferentes tratamentos de solo-CD em relação ao controle. A maior bioassimilação de ambos os metais foi observada em T1 de ambos os grupos (Pb = 563,8 mg / kg e Cd = 42,95 mg / kg). O conteúdo de ambos os metais foi significativamente (P ˂ 0,05) reduzido na fundição. A concentração de nutrientes nas fundições finais de todos os tratamentos de solo-CD também foi igualmente transformada de menos ou insolúvel para mais solúvel e disponível para as plantas, exceto o nível de carbono que aumenta com a proporção de CD. Conclui-se que o esterco de vaca como matéria orgânica tem um efeito positivo na recuperação do solo e na bioassimilação de metais por P. posthuma.

Abstract To investigate the role of cow dung in soil reclamation and bio assimilation along with bio accumulation of heavy metals in earthworm (P. posthuma) (N=900) earthworms were used and treatment groups of CD-soil mixture of different proportion of cow dung were designed. Nonlethal doses of lead acetate and cadmium chloride were added in treatment groups. Mature P. posthuma were released in each experimental pot maintaining the favorable conditions. The pH, carbon, nitrogen, phosphorus, exchangeable cations, and heavy metal level of each mixture was evaluated. The results indicated that bio-assimilation of Pb and Cd by P. posthuma were significantly (P ˂ 0.01) higher in different soil-CD treatments compared to control. Highest bio-assimilation of both metals was observed in T1 of both groups (Pb = 563.8 mg/kg and Cd = 42.95 mg/kg). The contents of both metals were significantly (P ˂ 0.05) lowered in casting. The nutrient concentration in the final castings of all soil-CD treatments were also equally transformed from less or insoluble to more soluble and available for plants, except for carbon level which increased with CD proportion. It is concluded that cow dung as organic matter has a positive effect on soil reclamation and bio-assimilation of metals by P. posthuma.