Genotoxicity and mutagenicity in blood and drinking water induced by arsenic in an impacted gold mining region in Colombia.

Arsenic (As) is one of the most dangerous substances that can affect human health and long-term exposure to As in drinking water can even cause cancer. The objective of this study was to investigate the concentrations of total As in the blood of inhabitants of a Colombian region impacted by gold mining and to evaluate its genotoxic effect through DNA damage by means of the comet assay. Additionally, the concentration of As in the water consumed by the population as well as the mutagenic activity of drinking water (n = 34) in individuals were determined by hydride generator atomic absorption spectrometry and the Ames test, respectively. In the monitoring, the study population was made up of a group of 112 people, including inhabitants of four municipalities: Guaranda, Sucre, Majagual, and San Marcos from the Mojana region as the exposed group, and Montería as a control group. The results showed DNA damage related to the presence of As in blood (p < 0.05) in the exposed population, and blood As concentrations were above the maximum allowable limit of 1 µg/L established by the ATSDR. A mutagenic activity of the drinking water was observed, and regarding the concentrations of As in water, only one sample exceeded the maximum permissible value of 10 µg/L established by the WHO. The intake of water and/or food containing As is potentially generating DNA damage in the inhabitants of the Mojana region, which requires surveillance and control by health entities to mitigate these effects.

Genotoxicity effects in freshwater fish species associated with gold mining activities in tropical aquatic ecosystems.

The main aim of this study was to investigate total mercury (THg), methylmercury (MeHg) and arsenic (As) concentrations, and their genotoxic effects on fish species in freshwater habitats impacted by gold mining activities in the Mojana and Bajo Cauca regions (Northern Colombia). A total of 255 individuals of Prochilodus magdalenae (PM) and Hoplias malabaricus (HM) were collected in different areas of northern Colombia, 205 in the exposed groups: Mojana 1 (61), Mojana 2 (81) and Bajo Cauca (63); and 50 individuals in the control group. Dorsal muscle was analysed for pollutants and blood to perform micronucleus (MN) and erythrocytic nuclear alterations (ENA) tests. The results of the MN revealed statistically significant (p < 0.05) genetic damage in both PM (Mojana 1 = 29.7 ± 14.2; Mojana 2 = 25 ± 6.25; Bajo Cauca= 26.6 ± 10.6) and in HM (Mojana 1 = 17.7 ± 7.8; Mojana 2 = 20.4 ± 6.3; Bajo Cauca= 20.8 ± 9.8) compared to the control group (PM= 10.5 ± 3.6; HM= 9.1 ± 3.9). Likewise, the frequency of ENA was statistically higher in the exposed groups compared to the control group (p < 0.05). On the other hand, the concentrations of THg, MeHg and As found in tissue samples were significantly higher (p < 0.05) compared to the control group, being the Bajo Cauca region the area of highest risk due to high concentrations of THg (651.2 ± 344.5 µg/kg for HM and 678.5 ± 983.9 µg/kg for PM) and MeHg (504.6 ± 220.9 µg/kg for HM and 606.8 ± 886.4 µg/kg for PM). Results showed that mean THg values for both species in Bajo Cauca exceeded the WHO maximum limit (set in 500 µg Hg/kg) in fish for human consumption. Results suggest that DNA damage in erythrocytes is associated with the presence of Hg, MeHg and As, coming from mining activities.

Determination of arsenic chemical species in rice grains using high-performance liquid chromatography coupled to hydride generator with atomic fluorescence detector (HPLC-HG-AFS).

The objective of this work is the validation and implementation of an analytical method for the determination of arsenic chemical species in rice grain samples using High-performance liquid chromatography coupled to a hydride generator with atomic fluorescence detector (HPLC-HG-AFS). The extraction protocol developed was based on HNO3 0.28 M (90 °C, 2 h), microwave-assisted. The results showed recovery percentages of arsenite (As (III)) (99-101%), arsenate (As (V)) (91-96%), dimethylarsinic acid (DMA) (92-102%) and monomethylarsonic acid (MMA) (94-97%). The precision of the method presented coefficients of variation lower than 7% and 8% for repeatability and reproducibility respectively. The detection limits were 2.5, 3.75, 7.5 and 4.0 µg kg-1 for As (III), As (V), DMA and MMA respectively. The proposed methodology is reliable for the quantification of As species, because they are conserved during the extraction.•The extraction protocol developed was based on Microwave-assisted acid extraction.•This methodology offers good sensitivity, precision, accuracy, detection and quantification limits.•It was successfully applied to determination of arsenic chemical species in rice grains.

Mercury dynamics in macroinvertebrates in relation to environmental factors in a highly impacted tropical estuary: Buenaventura Bay, Colombian Pacific.

The environmental health of Buenaventura Bay, a highly impacted tropical estuary, is influenced by numerous human activities, including mining upstream. Large- and small-scale fishing plays an important role in the local economy, so we investigated the dynamic processes of bioaccumulation of mercury at basal trophic levels. Four samples were taken at each of the four locations in Buenaventura Bay during each of the four seasons of 2015. We measured the total mercury content (T-Hg, dry weight) in sediments and in muscle tissue across 17 macroinvertebrate species. The most abundant were the blue crab (C. arcuatus) and the mantis shrimp (S. aculeata aculeata). Blue crab showed an average muscle T-Hg value ​​exceeding the limit of 0.2 g·g-1, which is the maximum T-Hg level suggested for food consumption by vulnerable humans and populations: pregnant women, children, and the community that feeds from this source of protein on a daily basis. It was found that, 6.22% of individuals exceeded the 0.5 g·g-1 level, which is the maximum T-Hg level suggested for food consumption by the general population: the population that consumes it sporadically. Significantly high values ​​of T-Hg in blue crab and mantis shrimp occurred during low salinity conditions in the estuary, suggesting that Hg mainly originates from river runoff during the rainy season. Nevertheless, the biota-sediment accumulation factor (BSAF) was favored in high salinity, which could mean greater availability of Hg for higher levels of the estuarine food web in the dry season and in marine waters. In general, the T-Hg levels in some samples exceeded 0.2 g·g-1. Therefore this pollutant must be monitored due to its biomagnification potential and as a threat to human health, especially that for the local population of fishermen and their families.

Mercury, Methylmercury and other Heavy Metals in Fish in Colombia: Risk From Ingestion / Mercurio, metilmercurio y otros metales pesados en peces de colombia: riesgo por ingesta

RESUMEN En 2013 el pescado proporcionó a más de 3100 millones de personas casi el 20 % de la ingesta promedio de proteínas de origen animal per cápita (FAO, 2016). De acuerdo con el Programa de las Naciones Unidas para el Desarrollo (PNUD), en Colombia y, particularmente en las poblaciones ribereñas y costeras, el 90 % del consumo de proteína de origen animal proviene del pescado, como resultado de un acceso muy bajo a otro tipo de proteínas. Colombia enfrenta uno de los mayores problemas por contaminación ambiental a nivel mundial, generado en gran parte por el abuso de sustancias químicas para el aprovechamiento de minerales, mala disposición de aguas servidas y prácticas industriales y agrícolas inadecuadas, en cuerpos de aguas fundamentales para la dinámica poblacional de animales, vegetales y humanos. Como estrategia mundial para reducir los riesgos a la salud humana por consumo de pescado contaminado con metales pesados, se han considerado límites máximos permisibles, propuestos por diferentes entidades; sin embargo, el 31,5 % de los resultados de estudios publicados para Colombia, son superiores al límite permisible recomendado por la OMS (0,5 μg/g). Los resultados presentados en esta revisión evidencian la urgente necesidad de realizar estudios que evalúen el riesgo a la salud que enfrentan pobladores de zonas mineras y no mineras de Colombia, aportará también fundamentos científicos y bases para el establecimiento de ejes estratégicos que permitan la puesta en marcha de nuevos proyectos productivos que ofrezcan el acceso de la población a diversas fuentes de alimentación.

ABSTRACT In 2013, fish provided to more of 3100 million people about 20 % of the average intake of animal protein per capita (FAO, 2016). According to the United Nations Development Program (UNDP), in Colombia and, particularly in the coastal populations, 90 % of the protein consumption of animal origin comes from fish, mainly as a result of very low access comparing it with another type of proteins. Colombia faces one of the biggest problems due to global environmental pollution, generated in largely part by the abuse of chemical substances for the exploitation of minerals, poor disposal of wastewater and inadequate industrial and agricultural practices, in bodies of natural water essential for population dynamics of animals, plants and humans. As a global strategy to reduce the risks to human health from the consumption of fish contaminated with heavy metals, maximum permissible limits have been considered, proposed by different entities. However, 31.5 % of the results of studies published for Colombia, register higher than the permissible limit recommended by the WHO (0.5 μg/g). The results presented in this review, evidence the urgent need to conduct studies that assess the health risk faced by residents of mining and non-mining areas of Colombia, will also provide scientific foundations and bases for the establishment of strategic axes that permit the start-up of new productive projects, which offer the population access to various sources of food.

Biomagnification of Mercury in Fish from Two Gold Mining-Impacted Tropical Marshes in Northern Colombia.

Total mercury concentrations (T-Hg) and stable isotope ratios (δ15N and δ13C) were analyzed in the muscle of fish, collected at two marshes impacted by gold mining in Northern Colombia, to evaluate the seasonal and spatial behavior of these variables and mercury biomagnification based on their relationship with δ15N ratios in the fish. There was not significant (p > 0.05) seasonal differences (dry and rainy season) in δ15N and δ13C values in none marsh, suggesting that these fish species keep a similar feed pattern within each marsh along the year. However, there were significant differences (p < 0.05) between marshes in δ15N, δ13C, and T-Hg, as well as significant seasonal differences (p < 0.05) in T-Hg values for some species, suggesting the possible influence of factors, such as differences in length of food chains between marshes and different degree of anthropogenic impact in relation to human settlements, farmland, livestock (higher in Ayapel marsh), and gold mining activity (higher in La Raya marsh). Correlations analysis showed significant (p < 0.05) relationships between T-Hg concentrations and δ15N values, as well as trophic level, evidencing a T-Hg biomagnification process in the fish food chain from both marshes and consequently a potential health risk for human riverside inhabitants who eat these fish.

Cytogenetic damage in peripheral blood lymphocytes of children exposed to pesticides in agricultural areas of the department of Cordoba, Colombia.

Pesticides offer benefits, like optimization of agricultural production and disease control; however, these toxic substances can contaminate the environment and pose risks to human health. The aim of this study was to assess pesticide exposure and frequency of cytogenetic damage in infant populations in agricultural areas of the department of Córdoba, Colombia. Urine and peripheral blood samples were taken from children living in the villages of La Ceibita (municipality of Cereté), Cabuya (municipality of San Carlos), Aguas Negras (municipality of Montería), Pelayito (municipality of San Pelayo), and the city of Monteria (control group). The work evaluated biomarkers of exposure to pesticides (atrazine urinary concentrations (ATZ) and its metabolites) and biomarkers of cytogenetic damage (micronucleus frequency (MN), nuclear buds, and apoptotic cells in peripheral blood lymphocytes). Measurable ATZ concentrations and/or its metabolites were recorded in the Pelayito, Aguas Negras, and Cabuya zones, which had higher MN frequencies, nuclear buds, and apoptotic cells than the control. Infant exposure to one of the more-often used pesticides in the agricultural areas evaluated and an increasing trend in the frequency of markers of cytogenetic damage in the groups of the agricultural areas, as compared to the control group, were evident.

Perfil de la expresión génica en células sanguíneas aisladas de carpinteros expuestos a solventes orgánicos en Sucre (Colombia) / Gene expression profile in blood cells isolated from carpenters exposed to organic solvents in Sucre (Colombia)

Resumen Objetivo: El objetivo de este estudio fue evaluar la expresión de genes asociados con estrés oxidativo, inflamación y daño al ácido desoxirribonucleico (ADN) en trabajadores de carpinterías en Sucre (Colombia). Materiales y métodos: Aleatoriamente fueron seleccionados 41 individuos de sexo masculino: 28 expuestos y 13 controles, con edades entre 32.3±7.9 y 33.2±8.4 años, respectivamente. Se colectaron muestras de sangre periférica y se realizaron análisis hematológicos y de marcadores de daño hepático. En 24 individuos expuestos y 10 controles se realizó análisis de expresión génica para marcadores de estrés oxidativo, inflamación y daño al ADN usando reacción en cadena de la polimerasa en tiempo real. Resultados: Los parámetros hematológicos y de daño hepático estuvieron dentro de los valores de referencia. La expresión génica de la P53 y BCL-2, genes asociados con el daño al ADN, fue significativamente mayor para el grupo expuesto en comparación con el grupo control. Conclusión: En ausencia de cambios en marcadores hematológicos o de daño hepático, personas expuestas a solventes en Sucre tienen niveles de expresión elevados para los genes P53 y BCL-2. Estos genes podrían ser candidatos útiles como biomarcadores moleculares relacionados con la exposición a solventes.

Abstract Objective: The aim of this study was to evaluate the expression of genes related to oxidative stress, inflammation and deoxyribonucleic acid (DNA) damage in carpentry workers from Sucre, Colombia. Materials and methods: 41 male individuals were randomly selected, 28 exposed and 13 controls, with ages 32.3 ± 7.9 and 33.2 ± 8.4 years old, respectively. Peripheral blood samples were collected and used for hematological and liver damage markers analysis. Gene expression analysis for oxidative stress, inflammation and DNA markers was performed using Real-Time Polymerase Reaction on 24 exposed and 10 controls. Results: Hematological parameters and liver damage markers were found within the reference values. Gene expression of P53 and BCL-2, genes related to DNA damage, was significantly greater for the exposed group when compared with the control group. Conclusion: In the absence of hematological or hepatic damage markers, individuals exposed to solvents in Sucre have increased gene expression for P53 and BCL2. These genes may be useful candidates as molecular biomarkers related to solvent exposure.

Relationship between mercury levels in hair and fish consumption in a population living near a hydroelectric tropical dam.

In the present study, total mercury (T-Hg) concentrations were assessed in human hair samples (n = 76) and fish muscle (n = 33) collected at Urrá dam, upstream Sinú river, northwestern Colombia. Based on interviews with study participants, weekly intakes of total mercury (WIT-Hg) and methylmercury (WIMeHg) by fish consumption were also estimated. T-Hg concentrations in hair samples ranged from 0.40 to 24.56 µg/g dw. The highest concentrations were recorded in children (CH) (2-15 years old, n = 24) with significant differences (p < 0.05) with respect to women of childbearing age (WCHA) (16-49 years old, n = 29) and the rest of the population (RP) (n = 23), which were not significantly different. The highest T-Hg concentrations in muscle tissue were recorded in the carnivorous fish (0.65-2.25 µg/g wet weight, ww), with significant differences (p < 0.05) compared to non-carnivorous fish (0.16-0.54 µg/g ww). WIT-Hg recorded the highest values in CH (2.18-50.41 µg/kg/week), with significant differences (p < 0.05) with respect to WCHA (2.02-23.54 µg/kg/week) and RP (1.09-24.71 µg/kg/week), which were not significantly different. Correlation analysis showed a significant relationship between weekly fish consumption and hair T-Hg in CH (r = 0.37, p < 0.05) and WCHA (r = 0.44, p < 0.05). This association was also observed with the number of days per week with fish consumption in CH (r = 0.37, p < 0.05) and WCHA (r = 0.45, p < 0.05). These results suggest that Hg exposure in people inhabiting the Urrá dam should be carefully monitored, particularly in vulnerable groups such as CH and WCHA.

Acumulación de mercurio (Hg) por caña flecha (Gynerium sagittatum) (Aubl) Beauv. in vitro / Accumulation of mercury (Hg) by arrow cane (Gynerium sagittatum) (Aubl) Beauv. in vitro

En este estudio se evaluó, in vitro, la capacidad de acumulación de mercurio (Hg) que pueda poseer la caña flecha (Gynerium sagittatum) (Aubl) Beauv. como una alternativa viable de ser implementada para la rehabilitación de suelos contaminados. Este estudio fue realizado en el laboratorio de Biotecnología Vegetal de la Universidad de Sucre (9º18’ N, 75º23’ O). Se usó un diseño experimental de bloques al azar, un análisis de varianza para comparación de medias, una prueba de Tukey (p≤0,05) para la establecer las diferencias significativas entre los tratamientos, pruebas de normalidad (Kolmogorov-Smirnov) y test de homogeneidad de varianza de Bartlett. Los análisis de mercurio se realizaron en un espectrofotómetro de absorción atómica Thermo Electron S4, provisto de una celda con ventanas de cuarzo, por el método de espectroscopia de absorción atómica con vapor frío. Los resultados muestran que la parte de la planta que presenta mayor acumulación es la raíz con 55,98 µg g-1 HgT, seguida de los tallos-hojas con 14,84 µg g-1 HgT, valores relacionados con el grado de concentración del metal en el medio de cultivo. Además, la acumulación de mercurio en raíces y tallos aumentó con el tiempo. En conclusión, in vitro esta planta acumula Hg debido a las altas concentraciones en sus tejidos sin afectar la viabilidad de las plantas.

In this in vitro study was evaluated the potential for accumulation of mercury (Hg) that can hold the cane arrow (Gynerium sagittatum) (Aubl) Beauv. as a viable alternative to be implemented for the rehabilitation of contaminated soils. This study was conducted at the Plant Biotechnology Laboratory, University of Sucre (9º 18' N, 75° 23' W). An experimental design was randomized block, an analysis of variance to compare means, Tukey test (p ≤ 0.05) to establish significant differences between the treatments, tests of normality (Kolmogorov-Smirnov) and homogeneity test Bartlett variance. The mercury analyses were performed on atomic absorption spectrophotometer Thermo Electron S4, a cell equipped with quartz windows, by the method of atomic absorption spectrometry with cold steam. The results show that the plant part that presents the greatest accumulation is the root with 55.98 mg g-1 HgT, followed by the stems, leaves 14.84 g g-1 HgT and these values ​​are related to the degree of metal concentration in the culture medium. Furthermore, the accumulation of mercury in roots and stems increased with time. In conclusion, in vitro this plant accumulates due to the high Hg concentrations in their tissues without affecting the viability of plants.