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1.
Environ Manage ; 68(5): 720-737, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34212224

RESUMEN

Artisanal and small-scale mining (ASM) in sub-Saharan Africa creates considerable dynamics in rural landscapes. Many studies addressed the adverse effects of mining, but few studies use participatory spatial tools to assess the effects on land use. Hence, this paper takes an actor perspective to analyze how communities in a mixed farming-mining area in Ghana's Eastern Region perceive the spatial dynamics of ASM and its effects on land for farming and food production from past (1986) to present (2018) and toward the future (2035). Participatory maps show how participants visualize the transformation of food-crop areas into small- and large-scale mining, tree crops, and settlement in all the communities between 1986 and 2018 and foresee these trends to continue in the future (2035). Participants also observe how a mosaic landscape shifts toward a segregated landscape, with simultaneous fragmentation of their farming land due to ASM. Further segregation is expected in the future, with attribution to the expansion of settlements being an unexpected outcome. Although participants expect adverse effects on the future availability of food-crop land, no firm conclusions can be drawn about the anticipated effect on food availability. The paper argues that, if responsibly applied and used to reveal community perspectives and concerns about landscape dynamics, participatory mapping can help raise awareness of the need for collective action and contribute to more inclusive landscape governance. These findings contribute to debates on the operationalization of integrated and inclusive landscape approaches and governance, particularly in areas with pervasive impacts of ASM.


Asunto(s)
Agricultura , Minería , Productos Agrícolas , Ghana , Humanos , Percepción
2.
New Solut ; 31(1): 48-64, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33705238

RESUMEN

Scholarship on the health impacts of resource extraction displays prominent gaps and apparent corporate and neocolonial footprints that raise questions about how science is produced. We analyze production of knowledge, on the health impacts of mining, carried out in relation to the Canadian International Resources and Development Institute (CIRDI), a university-based organization with substantial extractive industry involvement and links to Canada's mining-dominated foreign policy. We use a "political ecology of knowledge" framework to situate CIRDI in the context of neoliberal capitalism, neocolonial sustainable development discourses, and mining industry corporate social responsibility techniques. We then document the interactions of specific health disciplinary conventions and knowledges within CIRDI-related research and advocacy efforts involving a major Canadian global health organization. This analysis illustrates both accommodation and resistance to large-scale political economic structures and the need to directly confront the global North governments and sectors pushing extractive-led neoliberal development globally.ResumenLa investigación sobre los impactos en la salud de la extracción de recursos naturales delata brechas importantes y huellas corporativas y neocoloniales, que plantean dudas acerca de cómo se produce la ciencia. Analizamos la producción de conocimiento sobre los impactos en la salud de la minería en relación con el Instituto Canadiense de Desarrollo y Recursos Internacionales (CIRDI, siglas en inglés), una organización universitaria que cuenta con participación sustancial de la industria extractiva y tiene vínculos con la política exterior de Canadá, la cual es dominada por intereses mineros. Utilizamos un marco de "ecología política del conocimiento" para situar a CIRDI en el contexto del capitalismo neoliberal, los discursos neocoloniales de desarrollo sostenible y las técnicas de responsabilidad social corporativa de la industria minera. Luego, documentamos las interacciones entre los conocimientos y convenciones disciplinarias de salud dentro de los esfuerzos de investigación y promoción relacionados con CIRDI que involucran a una importante organización canadiense de salud global. Este análisis muestra tanto la complacencia como la resistencia a las estructuras políticas económicas a gran escala, y la necesidad de confrontar directamente a los gobiernos y sectores del Norte global que manejan el desarrollo neoliberal impulsado por la extracción a nivel mundial.


Asunto(s)
Salud Global , Mineros , Canadá , Humanos
3.
Ecotoxicol Environ Saf ; 207: 111234, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32916529

RESUMEN

The activity and fate of heavy metals (HMs) from mining and smelting activities in farmland soil is of great significance to effectively prevent the excessive enrichment of HMs in crops. This study focuses on Baiyin area, a typical mining city in northwest China. In this example, the sources, speciation, and fate of HMs in the farmland soil, and the migration and enrichment characteristics of HMs in the different parts of crops planted in different areas were studied in detail combining the chemical sequential extraction and Pb isotope approaches. Results showed that the mean anthropogenic contributions of HMs in farmland soils were approximately 85%, 88%, 76%, and 41% for the ore district (OD), Xidagou sewage irrigation area (XSIA), Dongdagou sewage irrigation area, and the Yellow River irrigation area, respectively, and the risk that HMs were excessively accumulated in crops in OD and XSIA was high. Compared with soil residual fractions, the isotope ratios 206Pb/207Pb in non-residual fractions (1.1304-1.1669) were closer to the values of local ores, suggesting that anthropogenic HMs from mining and smelting activities were mainly enriched in the non-residual fractions. The isotope ratios 206Pb/207Pb in crops (1.1398-1.1686) further confirmed that those anthropogenic HMs were more easily absorbed and concentrated by crops. HMs contents in leaves from OD and XSIA were generally higher than that in roots, suggesting that atmospheric deposition in OD and XSIA had a greater impact on the HMs concentration of crop leaves,while the excess rate of HMs in grain/fruit was the lowest in all parts of crops. The division and classification of crop planting in mining area can effectively help minimize the risk that HMs from anthropogenic source enter the human body through the food chain.


Asunto(s)
Agricultura/métodos , Metales Pesados/análisis , Minería , Contaminantes del Suelo/análisis , China , Ciudades , Productos Agrícolas/química , Grano Comestible/química , Monitoreo del Ambiente/métodos , Granjas , Humanos , Raíces de Plantas/química , Ríos , Aguas del Alcantarillado , Suelo/química
4.
Rev. cienc. salud (Bogotá) ; 18(spe): 52-65, dic. 2020. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1126253

RESUMEN

Resumen Introducción: en este artículo, se presenta un análisis de la relación directa entre la técnica y la tecnificación extractivista de minerales en el histórico cerro Rico de Potosí (Bolivia) y la determinación social de la salud y la vida de la población potosina, a escalas general, particular y singular de relaciones de producción, poder y consumo generadoras de procesos críticos de salud-enfermedad. Desarrollo: desde la perspectiva de la transformación del espacio que propone Milton Santos, se analiza cómo, derivada del contexto histórico colonial de la minería en Potosí, surge la transformación instrumental que la explotación minera ha generado en el paisaje y la vida cotidiana de la población, de cuya fuerza de trabajo se abastece la mina. Conclusiones: se ilustran estas condiciones haciendo una descripción de las ocupaciones y de las enfermedades asociadas, así como de los inminentes efectos de la contaminación ambiental general, haciendo visible la naturalización de la enfermedad y la muerte en el trabajo minero por parte de las propias familias y de las instituciones involucradas.


Abstract Introduction: The article reviews the direct relationship between extractivist techniques and mineral technification in the historic Cerro Rico de Potosí, Bolivia, with health's social determination and the life of its population, as a general establishment, that has particular and singular relations of production, power, and consumption generating critical health-disease processes. Development: From the perspective of the transformation of space by technique, proposed by Milton Santos, the instrumental transformation generated by mining in the landscape and life of the population, whose labor force supplies the mine, deriving from the colonial historical context of mining in Potosi, is analyzed. Conclusions: A description illustrates these conditions of the occupations and associated diseases, as well as the pending effects of general environmental pollution, making visible the naturalization of the sickness and death in the mining work by the families themselves and the institutions involved.


Resumo Introdução: neste artigo se apresenta uma análise da relação direta da técnica e a tecnificação extrati-vista de minerais, no histórico Cerro Rico de Potosí, Bolívia, e a determinação social da saúde e vida da população de Potosí, no nível geral, particular e singular de relações de produção, poder e consumo geradoras de processos críticos de saúde-doença. Desenvolvimento: desde a perspectiva da transformação do espaço que propõe Milton Santos, se analisa como, derivada do contexto histórico colonial a mineração em Potosí, surge a transformação instrumental que a exploração mineira tem gerado na paisagem e a vida cotidiana da população, de cuja força de trabalho se abastece a mina. Conclusões: ilustram-se estas condições fazendo uma descrição das ocupações e das doenças associadas, assim como dos iminentes efeitos da contaminação ambiental geral, fazendo visível a naturalização da doença e morte no trabalho mineiro por parte das próprias famílias e as instituições envolvidas.

5.
Environ Geochem Health ; 42(11): 3965-3981, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32653967

RESUMEN

To investigate the risks posed by trace and rare earth elements (REEs) in two tropical uranium ore fields, metal concentrations from 50 vegetable samples (corn and soybean) and their corresponding agricultural soils were evaluated in a U mining area and a U-rich coal mining area in Brazil. Samples from both areas had metal concentrations (REE: La to Lu, and trace elements: As, Pb, Cd, Ni, Cu, Cr, Mn, Zn, Ba, U, Sr) that were higher than the guidelines proposed by the Brazilian environmental agency. Soils from the U mining area (Poços de Caldas) generally had higher contents of trace elements than the coal mining area (Figueira), with the exception of Ni and Cr, indicating a higher risk of pollution, which was confirmed by a pollution load index that was greater than unity. For both sites, concentrations of uranium in the soil and plants, its hazard quotients and the soil contamination factor were higher in agricultural fields closer to the mines, indicating that contamination and the consequent risks to human health were distance dependent. REE concentrations averaged 52.8 mg kg-1 in the topsoils and 0.76 mg kg-1 in the grains for Figueira, whereas higher values of 371 mg kg-1 (topsoils) and 0.9 mg kg-1 (grains) were found in Poços de Caldas. Based upon corn and soybean consumption, the estimated intake dose of the REE was lower than the intake dose predicted to be problematic for human health for both sites, indicating limited risk related to the ingestion of REE.


Asunto(s)
Productos Agrícolas/química , Metales de Tierras Raras/análisis , Contaminantes del Suelo/análisis , Uranio/análisis , Agricultura , Brasil , Minas de Carbón , Exposición Dietética/efectos adversos , Exposición Dietética/análisis , Monitoreo del Ambiente , Humanos , Minería , Nivel sin Efectos Adversos Observados , Medición de Riesgo , Suelo/química , Oligoelementos/análisis , Zea mays/química
6.
Chemosphere ; 261: 127679, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32717510

RESUMEN

It is important to understand the environmental fate and potential risks posed by metals and metalloids around mines and in legacy mining areas. In order to assess the bioavailable concentrations of several potentially toxic elements (PTEs: As, Pb, Cd, Ni, Cu, Cr, Mn, Zn, Ba, U) and rare earth elements (REEs: La to Lu), a multi-method evaluation of their concentrations/fractionation/speciation in soils was related to their biouptake in corn, for a region surrounding a legacy U mine in Brazil. Chemical fractions of the PTE and REE in soils were determined using the BCR (Community Bureau of Reference) sequential extraction procedure; a single extraction with Ca(NO3)2 and the diffusion gradient in thin films (DGT) technique. All techniques were better correlated to the metals accumulated by the crops as compared to total metal concentrations. Ba, Cu, Mn and Zn were shown to have high mobility and high bioaccumulation factors in the corn. Concentrations of U, As, Cd, and Pb were above threshold concentrations and strongly correlated, suggesting that they had a similar anthropogenic source. Geospatial modeling agreed with results from principal component analysis, indicating multiple sources for the contamination. Results highlighted the need for multi-method approaches when evaluating the long-term risks posed by PTEs and REEs in agricultural soils.


Asunto(s)
Monitoreo del Ambiente , Contaminantes del Suelo/análisis , Uranio/análisis , Agricultura , Bioacumulación , Brasil , Fraccionamiento Químico , Productos Agrícolas , Metaloides/análisis , Metales Pesados/análisis , Minería , Suelo
7.
Nature ; 583(7815): 242-248, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32641817

RESUMEN

Enhanced silicate rock weathering (ERW), deployable with croplands, has potential use for atmospheric carbon dioxide (CO2) removal (CDR), which is now necessary to mitigate anthropogenic climate change1. ERW also has possible co-benefits for improved food and soil security, and reduced ocean acidification2-4. Here we use an integrated performance modelling approach to make an initial techno-economic assessment for 2050, quantifying how CDR potential and costs vary among nations in relation to business-as-usual energy policies and policies consistent with limiting future warming to 2 degrees Celsius5. China, India, the USA and Brazil have great potential to help achieve average global CDR goals of 0.5 to 2 gigatonnes of carbon dioxide (CO2) per year with extraction costs of approximately US$80-180 per tonne of CO2. These goals and costs are robust, regardless of future energy policies. Deployment within existing croplands offers opportunities to align agriculture and climate policy. However, success will depend upon overcoming political and social inertia to develop regulatory and incentive frameworks. We discuss the challenges and opportunities of ERW deployment, including the potential for excess industrial silicate materials (basalt mine overburden, concrete, and iron and steel slag) to obviate the need for new mining, as well as uncertainties in soil weathering rates and land-ocean transfer of weathered products.


Asunto(s)
Agricultura , Dióxido de Carbono/aislamiento & purificación , Productos Agrícolas , Sedimentos Geológicos/química , Calentamiento Global/prevención & control , Objetivos , Silicatos/química , Atmósfera/química , Brasil , China , Política Ambiental/economía , Política Ambiental/legislación & jurisprudencia , Calentamiento Global/economía , India , Hierro/aislamiento & purificación , Minería , Política , Probabilidad , Silicatos/aislamiento & purificación , Acero/aislamiento & purificación , Temperatura , Factores de Tiempo , Estados Unidos
8.
RECIIS (Online) ; 14(2): 307-328, abr.-jun. 2020. ilus, graf
Artículo en Portugués | LILACS | ID: biblio-1102488

RESUMEN

O artigo objetiva analisar a cobertura midiática do desastre socioambiental ocorrido em 2018, em Barcarena, no Pará, e discutir tanto as diferenças entre a duração do desastre (prolongada) e a duração da cobertura (concentrada), quanto os direcionamentos de escuta entre a repercussão de eventos gerados por vozes oficiais/institucionais e a presença/ausência de vozes populares de comunidades e movimentos sociais. Como resultado, apresenta três momentos de análise dos dados coletados em clipping nacional ao longo de oito meses: uma análise quantitativa da frequência da cobertura indicando alcance e duração da visibilidade midiática; um recorte quanti-quali apontando como a mídia agenda e promove enquadramento por meio das fontes acionadas na produção da notícia; e uma análise qualitativa, na perspectiva de colonial, de como aparecem na cobertura do desastre as vozes historicamente silenciadas. Para compreender o desastre como processo, busca-se antes situar o contexto da mineração na Amazônia a partir do aporte da Ecologia Política.


The article aims to analyze the media coverage of the socio-environmental disaster that occurred in 2018, in Barcarena, Pará, and to discuss both the differences between the duration of the disaster (prolonged) and the duration of the coverage (concentrated), as well as the listening directions between the repercussion events generated by official/institutional voices and the presence/absence of popular voices from communities and social movements. As a result, it presents three moments of analysis of data collected in national clipping over eight months: a quantitative analysis of the frequency of coverage indicating reach and duration of media visibility; a quanti-quali cut pointing out how the media schedules and promotes framing through the sources used in the production of the news; a qualitative analysis, in the decolonial perspective, of how historically silenced voices appear in the coverage of the disaster. To understand disaster as a process, we first seek to situate the context of mining in the Amazon from the perspective of Political Ecology.


El artículo tiene como objetivo analizar la cobertura mediática del desastre socioambiental ocurrido en 2018, en Barcarena, en Pará, y discutir tanto las diferencias entre la duración del desastre (prolongada) y la duración de la cobertura (concentrada) en cuanto a los direccionamientos de la escucha entre la repercusión de eventos generados por voces oficiales/institucionales y la presencia/ausencia de voces populares de comunidades y movimientos sociales. Como resultado, presenta tres momentos de análisis de los datos recogidos en clipping nacional a lo largo de ocho meses: un análisis cuantitativo de la frecuencia de la cobertura indicando alcance y duración de la visibilidad mediática; un recorte cuanti-quali señalando cómo los medios de comunicación agenda y promueve encuadre a través de las fuentes impulsadas en la producción de las noticias; y un análisis cualitativo, desde la perspectiva decolonial, de cómo aparecen en la cobertura del desastre las voces históricamente silenciadas. Para entender el desastre como proceso se busca, primero, situar el contexto de la minería en la Amazonía a partir del aporte de la Ecología Política.


Asunto(s)
Humanos , Desastre Industrial , Contaminación Ambiental , Periodismo Ambiental , Comunicación Ambiental , Minería , Brasil , Recolección de Datos , Medios de Comunicación de Masas
9.
Environ Geochem Health ; 42(12): 4233-4244, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32328898

RESUMEN

Cd and Pb are common toxic contaminants prevailing in agricultural soils contaminated by mining activities. In this study, biochar was used to stabilize Cd and Pb contaminated soil for safe with three crops rotation condition within one year. Field experiments were carried out to investigate the effect of Litchi branch biochar (BC), pyrolyzed at 600 °C and applied at 4 rates [(0 t ha-1 (T0), 10 t ha-1 (T1), 20 t ha-1 (T2) and 30 t ha-1 (T3)]) on remediation of Cd and Pb in agricultural soil near Dabaoshan Mine in South China under a cucumber-sweet potato-rape rotation. The results showed that the application of BC can significantly increase the pH, cation exchange capacity and soil organic matter. After cultivation of crops, the pH values decrease gradually, with the biggest drop of 0.45 pH units in T3 treatment after rape cultivation. BC application increased the yield of three crops up to onefold to twofold in T3 treatment as compared to the control. The uptake of Cd and Pb in all three crops decreases with the increase in BC doses, which is mainly related to the decrease in bioavailable metals in their respective soil treatments. Under 1-year crops rotation, the remediation ability of BC still remains, while Cd and Pb can exhibit different risk to different crops. The data of this study can provide scientific suggestions for the selection of suitable crops and proper BC amount in remediation of heavy metal contaminated soil.


Asunto(s)
Cadmio/química , Carbón Orgánico , Productos Agrícolas/química , Cucumis sativus/química , Ipomoea batatas/química , Plomo/química , Contaminantes del Suelo/química , China , Metales Pesados/análisis , Minería
10.
Chemosphere ; 244: 125543, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32050340

RESUMEN

Environmentally friendly and cost-effective techniques are required to reclaim land degraded during mining activities. Bioaccumulation of heavy metals (HMs) in vegetables grown on contaminated soils can increase human health risks. The potential effects of hardwood biochar (HWB) was assessed for chromium (Cr), zinc (Zn), copper (Cu), manganese (Mn) and lead (Pb) bioavailability in mine-contaminated soils and their subsequently bioaccumulation in crops and associated health risk. HWB was applied to chromium-manganese mine contaminated soils at the rate of 3% to investigate the efficiency of HWB for the second crop in crop rotation technique. Cilantro (Coriandrum sativum) and spinach (Spinaccia oleracea) were grown as second crop in the same pots which were already used for rice cultivation as first crop (without adding further amendments). Application of HWB decreased the concentrations of Cr, Zn, Cu, Mn, and Pb in cilantro by 25.5%, 37.1%, 42.5%, 34.3%, and 36.2%, respectively as compared to control. In spinach, the reduction in concentrations of Cr was 75.0%, Zn 24.1%, Cu 70.1%, Mn 78.0%, and Pb 50.5% as compared to control. HWB significantly (P < 0.01) reduced the HMs uptake in spinach cultivated in the amended soils as compared to the spinach in control. Bioaccumulation factor results also indicate that HWB decreased the bioaccumulation of selected HMs in cilantro and spinach, thus reducing health risks. Results of the study clearly demonstrate that the use of HWB can significantly reduce HMs in vegetables, associated health risk and improve food quality, therefore can be used as soil amendment for reclamation of mine-degraded soils.


Asunto(s)
Carbón Orgánico , Coriandrum/metabolismo , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo , Spinacia oleracea/metabolismo , Agricultura/estadística & datos numéricos , Disponibilidad Biológica , Cobre/metabolismo , Productos Agrícolas/metabolismo , Exposición Dietética/estadística & datos numéricos , Humanos , Manganeso/metabolismo , Metales Pesados/análisis , Minería , Oryza/metabolismo , Suelo , Contaminantes del Suelo/análisis , Verduras/metabolismo , Zinc/análisis
11.
Environ Monit Assess ; 192(2): 126, 2020 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-31960162

RESUMEN

This study evaluates the concentrations of lead (Pb) in 6 selected vegetables and drinking water samples taken from an agricultural/mining town Ishiagu. This evaluation is important because these vegetables and water are major gateway of lead exposure through ingestion, especially children in the Pb mining environment. Pb at even very low concentrations has been shown to have adverse effect on developing brain and hence children's intellectual ability. The impact of lead-contaminated food/water intake on the cognitive function was focused on school children whose parents have lived in the Pb mining town for over 25 years before they were born. Non-invasive, "target risk quotient" (TRQ) methodology, based on the principle of predictive toxicology was adopted for our analysis. Samples of these vegetables harvested in July and August 2015, and water taken from homes at 4 different villages in Ishiagu town and neighbouring community Akaeze (control), were subjected to appropriate chemical treatment/digestion procedures and the concentrations of Pb determined using AA-700 Shimadzu model atomic absorption spectrophotometer. From 642 structured questionnaire administered to the teachers/children, the daily vegetable ingestion rates for each vegetable (mg/child/day) and estimated daily intakes (EDI) of lead were obtained. The results show that the concentrations of Pb in water samples and the 6 vegetables harvested from the lead mining town vary as distances increase from the mining sites while the total target hazard quotients (TTHQs) for the vegetable crops were greater than one (˃ 1). The cognitive functions of 160 school children (aged 6-8 years), sampled from 265 families based on their meeting the criteria for distances away from the mining site, were evaluated using Raven's Standard Progressive Matrices and psychometrics. The data generated were analysed using (SPSS) version 21.0 and results expressed as mean ± standard deviation of intelligent quotient (IQ). Students' t tests for independent samples were used to compare the IQ results for children in the lead mining area and non-mining area. A model based on predictive toxicology paradigm which can show a relationship between concentrations of lead in vegetables/water and cognitive function was developed. This model shows that there is a positive correlation between total lead concentrations in vegetables/water and children's cognitive function.


Asunto(s)
Exposición a Riesgos Ambientales/estadística & datos numéricos , Plomo/análisis , Contaminantes del Suelo/análisis , Verduras/química , Agricultura , Niño , Ciudades , Productos Agrícolas , Agua Potable/análisis , Agua Potable/química , Monitoreo del Ambiente , Femenino , Contaminación de Alimentos/análisis , Humanos , Masculino , Metales Pesados/análisis , Minería , Medición de Riesgo
12.
Environ Geochem Health ; 42(12): 4073-4086, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31953626

RESUMEN

In Portugal, many abandoned mines are often close to agricultural areas and might be used for plant food cultivation. Soils in the vicinity of two Mn- and Fe-abandoned mines (Ferragudo and Rosalgar, SW of Portugal) were collected to cultivate two different food species (Brassica rapa subsp. pekinensis (Lour.) Hanelt and Origanum vulgare L.). Chemical characterization of the soil-plant system and potential risk of adverse effects for human health posed by plants associated with soil contamination, based on the estimation of hazard quotient (HQ), were assessed in a microcosm assay under greenhouse conditions. In both soils, the average total concentrations of Fe and Mn were above the normal values for soils in the region and their concentration in shoots of both species was very high. Brassica rapa subsp. pekinensis grew better in Ferragudo than in Rosalgar soils, and it behaved as an excluder of Cu, Mn, Fe, S and Zn in both soils. The HQ for Cu, Fe, Mn and Zn in the studied species grown on both soils was lower than unit indicating that its consumption is safe. The high Mn tolerance found in both species might be due in part to the high contents of Fe in the soil available fraction that might contribute to an antagonism effect in the uptake and translocation of Mn. The obtained results emphasize the need of further studies with different food crops before cultivation in the studied soils to assess health risks associated with high metal intake.


Asunto(s)
Brassica/química , Metales Pesados/análisis , Minería , Origanum/química , Contaminantes del Suelo/análisis , Brassica/efectos adversos , Productos Agrícolas/efectos adversos , Productos Agrícolas/química , Humanos , Origanum/efectos adversos , Portugal , Medición de Riesgo , Suelo/química
13.
Chemosphere ; 246: 125706, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31884227

RESUMEN

Zinc (Zn) is naturally present in soils and constitutes an essential micronutrient for plants. Mining, industrial, as well as various agricultural activities all contribute to increasing the Zn concentrations in soils to levels that are toxic for plants. The aim of this study was to evaluate the capacity of field crops to remove Zn from contaminated soils. The experimental design included 28 treatments, comprising seven field crops (Hordeum vulgare L., Ricinus communis L., Phaseolus vulgaris L., Brassica juncea Czem., Sorgum vulgare L., Spinacea oleracea L., Solanum lycopersicum L.) and four Zn levels (0, 500, 1000, 1500 mg kg-1) applied to soils. The dry weight (DW) of the aboveground biomass of R. communis and S. lycopersicum increased significantly as the Zn concentration in the soil increased, whereas the DW significantly decreased in P. vulgaris, B. juncea and S. vulgare. Results indicated that S. oleracea was the most efficient in concentrating Zn in the aboveground tissues, followed in decreasing order by H. vulgare, S. lycopersicum, R. communis, S. vulgare, P. vulgaris, and B. juncea. H. vulgare resulted the most efficient in accumulating Zn both in fruit and in leaves and stems, whereas S. lycopersicum resulted the most efficient in accumulating Zn in roots. The BAF and TF values indicated that H. vulgare and S. oleracea resulted being suitable for Zn phytoextraction, whereas the remaining crops being suitable for Zn phytostabilization. These results highlight the phytoremediation potential of the seven analysed crops.


Asunto(s)
Biodegradación Ambiental , Productos Agrícolas , Contaminantes del Suelo/análisis , Zinc/análisis , Biomasa , Hordeum , Metales Pesados/análisis , Minería , Planta de la Mostaza , Raíces de Plantas/química , Suelo , Spinacia oleracea , Oligoelementos/análisis
14.
Environ Geochem Health ; 42(7): 2205-2214, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31863322

RESUMEN

Sri Lanka's largest mineral sand deposit occurs in Pulmoddai, and the surrounding area of the mineral sand deposit has been identified as a high natural background radiation area. The food crops grown in the area are used for human consumption. However, the long-term consumption of high radioactive foodstuff may cause health defects. The objective of the present study was to assess the radiological impact on individuals due to ingestion of foodstuffs grown in Pulmoddai area. Seasonal food crops growing in the area, including cereals, vegetables, nuts, fruits and yams were collected and used to prepare common meal plans consumed by the residents. Samples were analyzed with high-purity germanium gamma spectrometer for activity concentrations. Activity concentration of 40K was observed in higher amounts in every food sample. Trace amounts of 137Cs 232Th and 7Be were also identified. The total committed effective dosage to an adult from gamma-emitting radionuclides from cooked meals was 0.1482 mSv year-1, and raw foodstuff was 0.0667 mSv year-1, which are far below than the harmful levels declared by International Atomic Energy Agency. Results concluded that foodstuff and cooked meals consumed by the people who live in Pulmoddai, Sri Lanka, are radiologically safe.


Asunto(s)
Exposición Dietética/análisis , Contaminación Radiactiva de Alimentos/análisis , Minerales/química , Radioisótopos/análisis , Adulto , Radiación de Fondo , Productos Agrícolas/química , Productos Agrícolas/clasificación , Exposición Dietética/normas , Humanos , Minería , Sri Lanka
15.
Environ Geochem Health ; 42(7): 1965-1976, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31705399

RESUMEN

The pollution from large-scale manganese mining and associated industries in Xiangtan (south Central China) has created a significant burden on the local environment. The proximity of mining, and other industrial activity to the local population, is of concern and impact of past industrial on the food chain was evaluated by the assessment of common food groups (rice, soybean, and sweet potato), and the associated soil and water in the region. We focused on specific potentially toxic elements (PTEs): Mn, Pb, Cd, Cr, Cu, and Zn associated with industrial activity, identifying the distribution of pollution, the potential significance of total health index (THI) for local people and its spatial distribution. The study area showed severe contamination for Mn, followed by Cd and Pb, while other PTEs showed relatively light levels of pollution. When analyzing the impact on crops exceeding the tolerance limit, the dominant PTEs were Mn, Cd, and Pb, with lower significance for Zn, Cu, and Cr. The average THI value for adults is 4.63, while for children, is 5.17, greatly exceeding the recommended limit (HQ > 1), confirming a significant health risk. In the spatial distribution of the THI, the region shows strong association with the transport and industrial processing infrastructure. Long-term management needs to consider remediation aligned to specific industrial operations and enhance contamination control measures of ongoing activity.


Asunto(s)
Productos Agrícolas/química , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis , Adulto , Niño , China , Agua Potable/análisis , Monitoreo del Ambiente , Cadena Alimentaria , Contaminación de Alimentos/análisis , Humanos , Industrias , Ipomoea batatas/química , Metales Pesados/toxicidad , Minería , Oryza/química , Medición de Riesgo , Contaminantes del Suelo/toxicidad , Soja/química , Contaminantes Químicos del Agua/toxicidad
16.
Environ Geochem Health ; 42(1): 191-207, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31140133

RESUMEN

Thirty soil samples and 24 corresponding unpolished rice samples along the Red and Huong Rivers in northern and central Vietnam respectively, were analyzed in order to evaluate (a) soil geochemistry, (b) factors that determine the transfer of harmful and nutrient elements from soils into rice grains, (c) health risk to the local population through rice consumption. The concentrations of As, Bi, and U in the soils of this area are higher relative to those of average shale probably due to natural redox-related processes. Also, Zn, Ce, Th, La, Sn, Pb, and Cd are accumulated in some soils because of mining activities or industrial wastewater application. Arsenic concentrations exceed the Vietnamese allowable limit of 15 mg kg-1 in 80% of the tested soils. Twelve percent of the unpolished rice grains surpass the permissible maximum concentration of 0.2 mg Cd kg-1 grain dry matter by FAO/WHO and European Union, and all samples are below the Pb limit. The daily intake of As is within the range of the tolerable intake levels proposed by the European Food Safety Authority. Influences of soil parameters such as pH value, contents of soil organic matter, oxides/hydroxides of Al, Fe, and Mn cause a broad spread of transfer factors from soil to grains. Positive trends exist between the transfer factors within the groups (a) As, Sb, and U, (b) Co, Cu, Ni, and Zn, (c) Cd and Mn which indicate similar influences of soil parameters on their uptake. We propose that the allowable Cd maximum concentration for rice should be set to less than 0.2 mg kg-1. The analysis of As and Cd concentrations in soils and corresponding rice grains as well as the soil pH value should be made obligatory in order to prevent intoxication. In addition, critical elements from nonferrous metal mining and industrial areas should also be evaluated.


Asunto(s)
Metales/análisis , Oryza/química , Contaminantes del Suelo/análisis , Suelo/química , Cadmio/análisis , Industria Química , Productos Agrícolas/química , Humanos , Minería , Nivel sin Efectos Adversos Observados , Ríos , Vietnam , Aguas Residuales
17.
Environ Geochem Health ; 42(4): 1069-1094, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31134395

RESUMEN

Heavy metals are of environmental significance due to their effect on human health and the ecosystem. One of the major exposure pathways of Heavy metals for humans is through food crops. It is postulated in the literature that when crops are grown in soils which have excessive concentrations of heavy metals, they may absorb elevated levels of these elements thereby endangering consumers. However, due to land scarcity, especially in urban areas of Africa, potentially contaminated land around industrial dumps such as tailings is cultivated with food crops. The lack of regulation for land-usage on or near to mine tailings has not helped this situation. Moreover, most countries in tropical Africa have not defined guideline values for heavy metals in soils for various land uses, and even where such limits exist, they are based on total soil concentrations. However, the risk of uptake of heavy metals by crops or any soil organisms is determined by the bioavailable portion and not the total soil concentration. Therefore, defining bioavailable levels of heavy metals becomes very important in HM risk assessment, but methods used must be specific for particular soil types depending on the dominant sorption phases. Geochemical speciation modelling has proved to be a valuable tool in risk assessment of heavy metal-contaminated soils. Among the notable ones is WHAM (Windermere Humic Aqueous Model). But just like most other geochemical models, it was developed and adapted on temperate soils, and because major controlling variables in soils such as SOM, temperature, redox potential and mineralogy differ between temperate and tropical soils, its predictions on tropical soils may be poor. Validation and adaptation of such models for tropical soils are thus imperative before such they can be used. The latest versions (VI and VII) of WHAM are among the few that consider binding to all major binding phases. WHAM VI and VII are assemblages of three sub-models which describe binding to organic matter, (hydr)oxides of Fe, Al and Mn and clays. They predict free ion concentration, total dissolved ion concentration and organic and inorganic metal ion complexes, in soils, which are all important components for bioavailability and leaching to groundwater ways. Both WHAM VI and VII have been applied in a good number of soils studies with reported promising results. However, all these studies have been on temperate soils and have not been tried on any typical tropical soils. Nonetheless, since WHAM VII considers binding to all major binding phases, including those which are dominant in tropical soils, it would be a valuable tool in risk assessment of heavy metals in tropical soils. A discussion of the contamination of soils with heavy metals, their subsequent bioavailability to crops that are grown in these soils and the methods used to determine various bioavailable phases of heavy metals are presented in this review, with an emphasis on prospective modelling techniques for tropical soils.


Asunto(s)
Metales Pesados/farmacocinética , Minería , Contaminantes del Suelo/farmacocinética , África , Disponibilidad Biológica , Productos Agrícolas , Ecosistema , Agua Subterránea/análisis , Agua Subterránea/química , Humanos , Metales Pesados/análisis , Estudios Prospectivos , Suelo/química , Contaminantes del Suelo/análisis , Clima Tropical , Contaminantes Químicos del Agua/análisis
18.
Environ Pollut ; 254(Pt B): 113089, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31476672

RESUMEN

The agricultural land-atmospheric dustfall-plant system around the mining area is at high risks of heavy metal pollution caused by mining-smelting activities. In this study, 118 samples (including rhizospheric soils, background soils, soil-forming parent rocks, crops, vegetables, medicinal plants and atmospheric dustfall) were collected nearby Tongling Cu-Fe-Au mining area, Eastern China. We studied the concentrations, migration, sources, and health risks through consumption of two main crops (corn and rice), six kinds of vegetables, and medicinal plants (Fengdan, Paeonia ostii) for six metal elements (Cu, Zn, Cr, Cd, Pb and Hg). Results revealed Cr and Cd in soils, and Cd, Cr, Pb, Cu and Zn in dustfall showed a relatively high contamination degree. The mean contents of Cr and Pb in corn kernels, as well as Cd, Cr and Pb in rice grains and all vegetables, and Cr in Fengdan cortex moutan exceeded the corresponding food safety limits in China. The transfer capability of Cr in corn kernels and rice grains, Pb in edible vegetables, and Cd in cortex moutan were the strongest, respectively. Health risk assessment results showed Cr had the greatest non-carcinogenic risk, followed by Pb and Cd. The results of pearson's correlation analysis (CA), hierarchical cluster analysis (HCA), and principal component analysis (PCA) indicated Zn-Cr, Pb and Cd-Cu-Hg in the plants might derive from different geochemical end-members. Source apportionment based on lead isotope showed that mining-smelting activities were the major source of Pb in atmospheric dustfall and agricultural soils, with the average contribution rates of 66% and 50%, respectively. Vehicle emissions from diesel fuels (50%-68%) and mining-smelting activities (16%-25%) contributed mainly to Pb accumulation in plants. Hence, our study suggested the accumulations of Pb in plants might be mainly from the direct foliar uptake of atmospheric Pb related to vehicle emissions and mining-smelting activities.


Asunto(s)
Productos Agrícolas/química , Monitoreo del Ambiente , Metales Pesados/análisis , Minería , Contaminantes del Suelo/análisis , Suelo/química , China , Contaminación Ambiental/análisis , Metales Pesados/química , Medición de Riesgo , Contaminantes del Suelo/química
19.
Chemosphere ; 235: 849-857, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31284133

RESUMEN

China has considered different environmental management measures (EMMs) in mining areas. However, their effects remain unclarified. In this study, the achievements and limitations of different EMMs of a typical mining area-Huangchang realgar mine-located in Hunan province were explored. The variations in the arsenic concentrations in the soil, agricultural products, drinking water, and atmosphere in 25 years of EMM implementation were investigated. Source control measures, such as ceasing mining and smelting activities, disposal of waste residues, and purifying wastewater, significantly reduced the arsenic concentrations in the atmosphere and surface water by more than 99%-from 68 µg m-3 and 0.42 mg L-1 to 3.63 ng m-3 and 4.31 µg L-1, respectively. The arsenic concentrations in agricultural products decreased by more than 78.8%-from 1.32 mg kg-1 in wheat to 0.28 mg kg-1 in vegetable and 0.13 mg kg-1 in maize-after the planting structure adjustment (PSA). However, the chronic daily intake of arsenic via product ingestion was 1.5 times higher than the benchmark dose lower confidence limit. Natural attenuation measures exerted limited effects on soil remediation; the arsenic concentration in the soil decreased insignificantly from 291.9 mg kg-1 to 213.3 mg kg-1. With the current attenuation rate, decreasing the soil arsenic concentration to under 30 mg kg-1 would require 47,900 years. The exceeding contaminant concentration in the resuspended dust, surface runoff, and agricultural products from the contaminated soil must be considered. China's EMMs in mining areas have achieved significant results, but the contaminated soil requires more attention and the PSA should accommodate the dietary habits and economic limits.


Asunto(s)
Arsénico/análisis , Productos Agrícolas/química , Agua Potable/química , Minería , Contaminantes del Suelo/análisis , Suelo/química , Agricultura , China , Polvo/análisis , Monitoreo del Ambiente , Contaminación Ambiental/análisis , Poaceae/química , Eliminación de Residuos
20.
Sci Total Environ ; 657: 938-944, 2019 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-30677959

RESUMEN

We studied the effect of different doses (0.5%, 2% and 5% (w/w)) of ammonium thiosulfate on mercury (Hg) speciation fractionation following its addition to the soil, as well as its accumulation by oilseed rape (Brassica napus L.), corn (Zea mays L.), and sweet potato (Ipomoea batatas L.), and compared them to a non-treated control in a historically polluted soil. The oilseed rape, corn, and sweet potato were planted consecutively in the same soils on days 30, 191, and 276, respectively after the addition of thiosulfate to the soil. The key results showed that bioavailable Hg contents in the rhizosphere soils ranged from 0.18 to 2.54 µg kg-1, 0.28 to 2.77 µg kg-1, and 0.24 to 2.22 µg kg-1, respectively, for the 0.5%, 2% and 5% thiosulfate treatments, which were close to the control soil (0.25 to 1.98 µg kg-1). The Hg L3-edge X-ray absorption near edge structure (XANES) results showed a tendency of the Hg speciation to transform from the Hg(SR)2 (initial soil, 56%; day-191 soil, 43%; day-276 soil, 46%, and day-356 soil, 16%) to nano particulated HgS (initial soil, 26%; day-191 soil, 42%; day-276 soil, 42%, and day-356 soil, 73%) with time in the soil treated with a 5% dose of thiosulfate. The Hg contents in the tissues of the crops, except for oilseed rape, were slightly affected by the addition of thiosulfate to the soil at all dosages, compared to the control. The addition of thiosulfate did not induce the movement of bioavailable Hg to the lower layer of the soil profile. We conclude a promotion of Hg immobilization by thiosulfate in the soil for over one year, offering a promising method for in-situ Hg remediation at Hg mining regions in China.


Asunto(s)
Productos Agrícolas/efectos de los fármacos , Restauración y Remediación Ambiental/métodos , Mercurio/química , Contaminantes del Suelo/química , Tiosulfatos/química , Disponibilidad Biológica , Brassica napus/efectos de los fármacos , Brassica napus/metabolismo , China , Productos Agrícolas/química , Ipomoea batatas/efectos de los fármacos , Ipomoea batatas/metabolismo , Mercurio/análisis , Mercurio/farmacocinética , Minería , Rizosfera , Contaminantes del Suelo/análisis , Contaminantes del Suelo/farmacocinética , Espectroscopía de Absorción de Rayos X , Zea mays/efectos de los fármacos , Zea mays/metabolismo
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