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1.
Environ Monit Assess ; 192(3): 155, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32006114

RESUMEN

Quantification of the contributions from traffic source to arable roadside soil heavy metal loadings is a challenge. The contribution depends on: traffic intensity, road type and distance from the road. At a field scale (3.9 ha), 720 topsoil samples were taken. The aim of the study was to monitor and assess the impact of regional/local roads with various conditions of traffic and period of use on the distribution of Cd, Zn, Pb and Cu in the arable roadside topsoil in their vicinity. PCA indicated the occurrence of two main gradients of 11 environmental elements influencing the distribution of heavy metals in the soils of the neighbouring land. The first gradient was associated mainly with the distance from the edge of the road. The second gradient was associated with the degree of contamination of the soils and with the road type, defined by the traffic volume and period of being use. Anova reviled lack of influence of the factors for Cu contents. Unlike Cu, for Cd, Pb and Zn, the significant impact was observed for both factors and interactions between them. The concentrations of Cd, Pb and Zn, regardless of the distance from the road were 0.21-0.58 mg Cd kg-1 d.m., 13.60-41.96 mg Pb kg-1 d.m. and 40.31-63.97 mg Zn kg-1 d.m. In case of increasing distance from the road, generally the contents of Pb, Zn and Cd contents were decreasing. However, only in the case the oldest and carrying the highest traffic road was a clear, statistically significant differences noted for following distances from the road on the content of Cd, Pb and Zn. Analysis of spread gave trend curves, for Pb, Cd and Zn they were parabolas. The curves let reduce sapling distances to 65 m, 45 and 47 m for Cd, Pb and Zn, respectively.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Cadmio , Cobre , Monitoreo del Ambiente , Plomo , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisis , Emisiones de Vehículos , Zinc
2.
Environ Monit Assess ; 192(3): 162, 2020 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-32020303

RESUMEN

The aim of this study was to quantify heavy metal pollution for environmental assessment of soil quality using a flexible approach based on multivariate analysis. The study was conducted using 241 soil samples collected from agricultural, urban and rangeland areas in northwestern Iran. The heavy metals causing soil pollution (SP) in the study area were determined. The efficiency of principal component analysis (PCA) and discriminate analysis (DA) were compared to identify the critical heavy metals causing SP. Fourteen soil pollution indices were developed using non-linear and linear scoring equations and different integration methods. The indices were validated using the integrated pollution and potential ecological risk indices and by comparing their ability to detect soil pollution risk levels. Chromium (Cr), lead (Pb), Zinc (Zn) and copper (Cu) were identified as the significant pollutant elements using PCA, and the main pollutant elements identified using DA comprised cadmium (Cd), Zn and Pb. DA yielded a better data set for indexing SP and indicated high pollution risks for Cd > Pb > Zn. Sources of heavy metals were reliably identified using PCA, variation assessment and interrelationship evaluation of soil variables. Cr, nickel (Ni) and cobalt (Co) were found to have geogenic sources, and anthropogenic sources controlled the accumulation of Pb, Zn, Cd and Cu in soil. Linear function and additive integration were the best scoring and integrating methods for indexing HMP. The multivariate analysis provided a reliable and rapid method for indexing and mapping soil HMP.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , China , Monitoreo del Ambiente , Contaminación Ambiental , Irán , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
3.
Environ Monit Assess ; 192(3): 164, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-32025899

RESUMEN

Vegetable gardening in floodplains in western Nigeria has assumed economic significance but with attendant pressure on urban field in the dry season. This study assessed soil properties and bioconcentration of cadmium (Cd), iron (Fe) and lead (Pb), in edible parts of Celosia argentea and Corchorus olitorius grown in floodplains. Soil and vegetable samples were collected at 20 m intervals from rural (Atoyo and Ewuga) and urban (GRA Rd. and Lafarge) floodplain gardens in Sagamu. Six samples were collected per location making a total of 24 samples each of soil and vegetable. Samples were analyzed for soil properties and heavy metal concentration in the vegetables. Transfer factor (TF), contamination factor (CF), daily intake of metals (DIM), health risk index (HRI) and geoaccumulation index (Igeo) were also determined. Soil properties varied significantly, with the highest soil concentration of Cd (0.91 mg kg-1) and Fe (208.20 mg kg-1) recorded at Lafarge. The highest soil Pb (223.77 mg kg-1) was at Atoyo. Bioaccumulation of Fe was significantly (p ≤ 0.05) higher in C. argentea than C. olitorius. Heavy metal bioaccumulation beyond allowable limits was recorded for Cd (0.46 mg kg-1) and Pb (49.30 mg kg-1) by C. argentea and C. olitorius, respectively. Soil contamination was dominated by Cd at Lafarge and by Pb at Atoyo. The DIM and HRI indices indicated no risk of Cd, Fe and Pb consumption in the vegetables. Geoaccumulation index revealed that Lafarge and Atoyo soils were extremely contaminated with Cd and Pb, respectively. Leafy vegetables grown in urban and rural floodplain soils adjacent to waste dumpsite are accumulators of Cd and Pb with food poisoning as the consequence.


Asunto(s)
Celosia , Corchorus , Metales Pesados , Contaminantes del Suelo , Verduras , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Nigeria , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis , Verduras/química
4.
Environ Monit Assess ; 192(3): 167, 2020 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-32030474

RESUMEN

Mountains are the preferred sites for studying long-range atmospheric transportation and deposition of heavy metals, due to their isolation and steep temperature decrease that favors cold trapping and condensation of particulate forms of heavy metals. Any enrichment of heavy metals in mountains is presumed to primarily occur through atmospheric deposition. In this particular study, we assessed the status of 27 subsurface soils collected along two elevation gradients of Mt. Kenya using enrichment factors (EFs) as the ecological risk assessments. The collected soils were analyzed for total organic carbon, zinc (Zn), iron (Fe), manganese (Mn), and copper (Cu). The mean concentration of Mn, Fe, Zn, and Cu was 0.376 mg/kg, 47.6 mg/kg, 12.3 mg/kg, and 4.88 mg/kg in Chogoria and 0.560 mg/kg, 113 mg/kg, 12.7 mg/kg, and 2.70 mg/kg in Naro Moru respectively. These concentrations were below the US-EPA maximum permissible levels for soils, implying that the levels recorded had low toxicity. Meanwhile, the mean enrichment factors for Mn, Cu, and Zn were 0.447, 131, and 78.8 in Chogoria and 0.463, 38.9, and 53.0 in Naro Moru respectively. This implied that Zn and Cu in Chogoria sites were extremely enriched, while in Naro Moru, enrichment levels ranged from significant to extreme. However, Mn was found to have minimal enrichment in all the sites. Lower montane forest and bamboo zone recorded relatively high enrichment due to distance from source of pollution. Ericaceous zone also had high mean enrichment due to influence of wind which favors higher deposition at mid-elevations.


Asunto(s)
Cobre , Manganeso , Metales Pesados , Contaminantes del Suelo , Zinc , Cobre/análisis , Monitoreo del Ambiente , Kenia , Manganeso/análisis , Suelo , Contaminantes del Suelo/análisis , Tanzanía , Zinc/análisis
5.
Environ Monit Assess ; 192(3): 178, 2020 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-32062705

RESUMEN

The present study was aimed at evaluating fluorine contamination of the eggs of free-ranging laying hens in Northern Poland, in the Central Pomerania region, in relation to the distance from the emission sources. Fluorine levels in the soil, feed, and the shells, and contents of the eggs were assayed with the potentiometric method using an ion-selective electrode from ORION Ion Meter. The sampled eggs were subjected to pressure microwave digestion with the use of a Milestone MLS-1200 microwave. All the samples were digested in 5 ml of supra-pure grade concentrated HNO3 from Merck. The mean level of fluorine in the studied soils ranged from 3.79 mg kg-1 of DM in typical river alluvial soil to 126.19 mg kg-1 of DM in lessive soil. The study revealed an average fluorine content in the feeds administered to the hens on the farms in zone 1 (17.29 mg kg-1 of DM), it being 3.5 times higher than the corresponding content in zone 2 (4.92 mg kg-1 of DM). A statistically significantly higher mean fluorine level was identified in the eggshells of hens on zone 1 farms, located closer to the pollution emission sources (17.52 mg kg-1 of DM), the value being more than 3-fold higher than that in zone 2 (5.47 mg kg-1 of DM). The present study revealed an almost twice as high fluorine mean content in the hen eggs collected on farms in zone 1 (1.488 mg kg-1 of DM) compared with the hen egg contents in the experimental zone 2 (0.640 mg kg-1 of DM), the difference being statistically significant.


Asunto(s)
Alimentación Animal , Pollos , Huevos , Fluoruros , Compuestos de Flúor , Contaminantes del Suelo , Animales , Monitoreo del Ambiente , Contaminación Ambiental , Femenino , Fluoruros/análisis , Polonia , Suelo , Contaminantes del Suelo/análisis
6.
Chemosphere ; 244: 125534, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32050335

RESUMEN

Perfluoroalkyl acids (PFAAs) bioaccumulate in crops, with uptake being particularly high for short-chain PFAAs that are constantly transported with transpiration water to aerial plant parts. Due to their amphiphilic surfactant nature and ionized state at environmental pH, predicting the partitioning behavior of PFAAs is difficult and subject to considerable uncertainty, making experimental data highly desirable. Here, we applied a plant uptake model that combines advective flux with measured partition coefficients to reproduce the set of empirically derived plant uptake and soil-partitioning data for nine PFAAs in red chicory, in order to improve the mechanistic understanding and provide new insights into the complex uptake processes. We introduced a new parameter for retarded uptake (R) to explain the slow transfer of PFAA across biomembranes of the root epidermis, which has led to low transpiration stream concentration factors (TSCFs) presented in literature so far. We estimated R values for PFAAs using experimental data derived for red chicory and used the modified plant uptake model to simulate uptake of PFAA into other crops. Results show that this semi-empirical model predicted PFAAs transport to shoots and fruits with good accuracy based on experimental root to soil concentration factors (RCFdw) and soil to water partition coefficients (Kd) as well as estimated R values and plant-specific data for growth and transpiration. It can be concluded that the combination of rather low Kd with high RCFdw and the absence of any relevant loss are the reason for the observed excellent plant uptake of PFAAs.


Asunto(s)
Ácidos Alcanesulfónicos/metabolismo , Fluorocarburos/metabolismo , Modelos Químicos , Plantas/metabolismo , Contaminantes del Suelo/metabolismo , Ácidos Alcanesulfónicos/análisis , Productos Agrícolas/crecimiento & desarrollo , Monitoreo del Ambiente , Fluorocarburos/análisis , Frutas/química , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/química , Tensoactivos/análisis
7.
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
8.
Chemosphere ; 244: 125548, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32050343

RESUMEN

Wheat (Triticum aestivum L.) cultivation in cadmium (Cd) polluted soil is a core concern to food quality and food security all over the world. Cadmium toxicity is mainly associated with a Cd influx from contaminated soils to human via grain consumption. Organic amendments are widely used for Cd immobilization and enhancement in plant growth, but the residual effects of these amendments are mostly unknown. The present study addressed the long-term effects of organic amendments in contaminated soils by evaluating their residual effects on 3rd crop (wheat) in the sequence. Initially six organic amendments viz. rice husk biochar (RHB), wheat-straw biochar (WSB), cotton-stick biochar (CSB), poultry manure (PM), press mud (PrMd) and farm manure (FM) were applied once at a rate of 2% in Cd (50 mg kg-1) contaminated soil with wheat-rice rotation. After the harvest of wheat and rice crops, wheat (Var. Galaxy) was again grown in the same pots. Results revealed that plants grown under Cd stress (without any amendment) contain more tissue (root, shoot and grain) and soil AB-DTPA extractable Cd. The soil amended with RHB has shown lowest AB-DTPA extractable Cd (69% lower than control). Similarly, RHB application has significantly reduced wheat root, shoot and grain Cd concentrations compared to control and other amendments. Results have confirmed the effectiveness of RHB residual contents as an active amendment for restriction of Cd in non-bioavailable pool of soil and better growth and yield of wheat.


Asunto(s)
Cadmio/metabolismo , Contaminantes del Suelo/metabolismo , Triticum/metabolismo , Disponibilidad Biológica , Cadmio/análisis , Carbón Orgánico , Productos Agrícolas , Grano Comestible/química , Estiércol , Oryza/crecimiento & desarrollo , Suelo , Contaminantes del Suelo/análisis , Triticum/crecimiento & desarrollo
9.
Environ Monit Assess ; 192(2): 111, 2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-31938942

RESUMEN

This study proposes a simple and effective method for determination of Al, Cd, Cu, Ni, and Zn in soil samples, associating ultrasound-assisted extraction and flame atomic absorption spectrometry (FAAS). Ultrasound-assisted extraction conditions were optimized using a central composite design. This method required small volumes of HCl, HNO3, and HF as an extraction solvent blend to ensure effective analyte extraction. Limits of detection and quantification were determined to assess the minimum accurate concentration of the studied elements that can be detected and quantified in a soil sample. Therefore, the ultrasound-assisted extraction was concluded as a simple and straightforward pretreatment technique to determine Al, Cd, Cu, Ni, and Zn concentrations in soil samples. Eight sites of agricultural and native forest areas of the city of Ponta Grossa and Guarapuava, State of Paraná, Brazil, were evaluated for metals, and compared with the reference values for trace elements provided by the Brazilian National Environment Council. Environmental assessment of soils from those eight sites was accomplished through Igeo, EF, CF, and PLI parameters, which aimed at the evaluation of agricultural sites in comparison with adjacent natural forest sites with no history of anthropogenic mobilization to determine the degree of the contribution of anthropogenic sources to metal concentrations. According to the Igeo, EF, and CF parameters, all sites were classified as unpolluted to moderately polluted and none or minor enrichment due to anthropogenic activities were noticed. PLI parameter evaluated the concentration of all studied metals in soils to stipulate an order of contamination, which was concluded as site 8

Asunto(s)
Metales Pesados , Contaminantes del Suelo , Oligoelementos , Brasil , Ciudades , Monitoreo del Ambiente , Bosques , Metales , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisis , Espectrofotometría Atómica
10.
Environ Monit Assess ; 192(2): 131, 2020 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-31965342

RESUMEN

A large number of human activities result in the release of potentially toxic elements (PTEs) into the environment, which could lead to the degradation of riparian areas. This study aimed to evaluate the potential of Salix alba, Juglans regia and Populus nigra for the biomonitoring of PTEs in the riparian soils of the Sava River. Levels of seven PTEs (As, Cd, Cr, Cu, Ni, Pb and Zn) were measured in the soils, roots and leaves of plants at selected sampling sites and evaluated according to bioaccumulation and translocation factors. The obtained results showed that in riparian soils, As, Cr, Cu, Ni and Zn were at levels considered to be critical for plants. The levels of As, Cd, Cr, Ni and Zn measured in roots of Salix alba and As, Cr, Ni and Zn in its leaves were toxic for plant tissue. Toxic levels of Cr were also measured in the roots of Juglans regia and As in its leaves, as well as As and Cr in the roots of Populus nigra, and Zn in its leaves. Bioconcentration and translocation factors showed that S. alba and P. nigra have potential for the phytoextraction of Zn and Cd, while J. regia has potential for the phytoextraction of As. In terms of phytostabilization potential, S. alba proved to be good for the phytostabilization of Cd and Cu, and J. regia for the phytostabilization of Cr, As, Ni and Pb, while P. nigra showed potential for the phytostabilization of Cr, Ni, Pb and Cu.


Asunto(s)
Juglans , Metales Pesados , Populus , Salix , Contaminantes del Suelo , Monitoreo del Ambiente , Humanos , Juglans/química , Populus/química , Ríos , Salix/química , Suelo , Contaminantes del Suelo/análisis
11.
Environ Monit Assess ; 192(2): 80, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31897755

RESUMEN

One of the major issues in surveying the sorption and mobility of elements is awareness of the behavior and reactions of elements in soils and their distribution coefficient (Kd) values. This study was conducted to investigate the adsorption of potassium (K), sodium (Na), calcium (Ca), and magnesium (Mg) in six calcareous soils saturated with mentioned cations. The initial equivalent fraction of K, Na, Ca, and Mg in solutions increased from 0.1 to 1 at a total electrolyte of 30 meq L-1. The shape of isotherm curves and the amount of cations adsorbed varied in different binary exchange systems. The adsorption of cations increased gradually with increasing initial concentrations. The average values of Kd (L kg-1) in different binary systems were arranged in the following order: Ca-Mg (23.4) > Mg-Na (21.5) > Mg-K (20.7) > Mg-Ca (20.1) > Ca-Na (16.0) > Ca-K (15.4) > K-Mg (5.6) > K-Na (5.0) > K-Ca (4.6) > Na-Ca (2.7) > Na-Mg (1.9) > Na-K (1.7). The average values of Gaines-Thomas selectivity coefficients of cations in different binary exchange systems followed this order: K-Ca (16.5) > K-Mg (7.8) > Ca-Mg (4.1) > Mg-Ca (3.1) > Mg-Na (2.1) > K-Na (1.7) > Mg-K (1.0) > Ca-Na (0.8) > Ca-Na (0.6) > Na-Ca (0.5) > Na-Mg (0.1) = Na-K (0.1). So, the affinity of cations for adsorption by soils followed this order: K > Ca > Mg > Na which differed from the classical lyotropic series. The high affinity of K for adsorption by soils was attributed to the presence of illite. The free cations were the most abundant species (above 90%) in all soil solutions after reaching equilibrium with initial concentrations of 3 and 30 meq L-1. The saturation index (SI) values of minerals in all exchange systems were negative.


Asunto(s)
Monitoreo del Ambiente , Contaminantes del Suelo/análisis , Adsorción , Calcio , Cationes , Magnesio , Minerales , Potasio , Sodio , Suelo/química
12.
Environ Monit Assess ; 192(2): 78, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31899536

RESUMEN

Food scarcity is one of global issues that our world faces today. A significant portion of the world's population has no access to adequate food, and it is stated that approximately 830 million people suffer from chronic famine. This predicament is estimated to grow even further. Many attempts have been made to solve the food problem. Some examples are using new resources which have not been used for dietary purposes up to this point, planting new areas to produce food products, and increasing the potential harvest per an area unit. One of the solution proposals, which has come up recently within this scope, is the term of "edible landscaping", which means the use of edible plants in the landscaping works, and thus maximizing the potential for food security. However, edible landscaping poses a considerable risk. Heavy metal accumulation in plants grown in urban centers can reach to high levels, and consuming these plants will allow these heavy metals a direct access into the human body and wreak havoc to the public health. But since this subject has not been sufficiently studied yet, the extent of such a risk is not accurately determined yet. This study aims to determine the changes of Ni, Co and Mn concentrations depending on traffic density in the leaves, branches, barks and fruits of cherry, plum, mulberry and apple trees growing in areas with dense traffic, low-density traffic and no-traffic zones in Kastamonu province. The results showed that the concentrations of Ni and Co elements increased in many organelles depending on traffic density, and that the heavy metal concentrations in fruits could be very high. This situation indicates that fruit and vegetables grown in industrial zones and urban centers, where heavy metal pollution may be high, can be harmful to the public health if consumed as crops.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Plantas Comestibles/química , Contaminación por Tráfico Vehicular/análisis , Emisiones de Vehículos/análisis , Contaminación Ambiental/análisis , Humanos , Contaminantes del Suelo/análisis
13.
Environ Monit Assess ; 192(2): 89, 2020 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-31902034

RESUMEN

Soybeans, as legumes, belong among food items that contribute most to the dietary intake of the heavy metal cadmium (Cd). The consumption of soy-based foods may contribute significantly to Cd intake in vegetarians as probably the most frequent consumers of these foods. In this research, the weekly dietary intake of Cd from soy-based foods was investigated in 119 participants (including vegetarians, vegans, and non-vegetarians) in the Czech Republic by means of a semi-quantitative food frequency questionnaire (SFFQ) with personal assistance and the measurement of body weight. Cd content in soy-based foods available on the market was determined by means of atomic absorption spectrometry after microwave digestion. Tofu, as the most frequently consumed food item in the vegetarian/vegan group, contributed most to the total dietary Cd intake. It contained 7.6 ± 0.1 µg Cd/kg, while the highest Cd content was observed in tempeh (18.1 ± 0.4 µg/kg). The highest mean dietary Cd intake per week from soy-based foods was 0.4 µg/kg b.w. and was found in the vegan group. The consumption of soy-based foods was the lowest in the non-vegetarian group as was the dietary intake of Cd, which was 0.04 µg/kg b.w. per week.


Asunto(s)
Cadmio/análisis , Exposición Dietética/estadística & datos numéricos , Contaminación de Alimentos/estadística & datos numéricos , Contaminantes del Suelo/análisis , Alimentos de Soja/análisis , Soja/química , Peso Corporal , República Checa , Dieta , Monitoreo del Ambiente , Fabaceae , Femenino , Humanos , Masculino , Espectrofotometría Atómica , Verduras , Vegetarianos
14.
Environ Monit Assess ; 192(2): 92, 2020 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-31902037

RESUMEN

The aim of the study was monitoring of phthalic acid esters in agricultural soils of the Czech Republic over the period of 6 years, namely dibutyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP). Monitoring took place in twelve regions of the Czech Republic. Soil samples were taken evenly from the top and bottom soil horizons using a zig-zag pattern. Soil samples were taken from arable land, permanent grassland, and hop field. Lyophilisation of the samples was done by ultrasound-assisted extraction using a mixture acetone-hexane (1:1). Phthalic acid esters were analysed using high-performance liquid chromatography with UV detection. Subsequently, the results were statistically compared by analysing the principal components (PCA) to determine the effect of individual factors on the content of phthalic acid esters in agricultural soil. Factors such as precipitation, distance from a pollution source, amount of pesticides, and amount of artificial and organic fertilizers were taken into account. If we compare the concentrations established in this study with the limits set out in the Methodological Instruction of the Ministry of the Environment of the Czech Republic based on RSLs (Regional Screening Levels) issued by the USEPA (United States Environmental Protection Agency), none of these values were exceeded.


Asunto(s)
Monitoreo del Ambiente , Ácidos Ftálicos/análisis , Contaminantes del Suelo/análisis , Agricultura , República Checa , Dibutil Ftalato/análisis , Dietilhexil Ftalato/análisis , Contaminación Ambiental/análisis , Ésteres/análisis , Plaguicidas/análisis , Suelo/química , Estados Unidos
15.
Environ Monit Assess ; 192(2): 115, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31940086

RESUMEN

Nowadays, the growing concern about the environmental problems affecting the subsoil has focussed efforts on the detection and characterization of contaminated sites through geophysical prospecting methods. In the present study, a case of a contaminated site by hydrocarbons and their study by means of time domain-induced polarization tomography is presented. The response in chargeability of porous media due to this kind of pollutant allows its delimitation using this method. However, one of the limitations for the application of this technique is the presence of lithologies that contain electro-metallic salts. These salts can produce anomalies of chargeability and mask those due to nonaqueous phase liquids. The studies were conducted in an area contaminated by fuel leaks from supply tanks within a train maintenance facility. Those leaks occurred while the tanks were in use, but since their dismantling, the leak stopped. The geology of the area presented strong heterogeneities and the access was limited by train tracks. In order to locate and characterize the contaminant plume, measurements of resistivity and chargeability were carried out. A grid of monitoring wells in this area was also available from which information about free-phase pollutants was obtained, and a new drilling was carried out to verify an unexpected anomaly. The results obtained show that the location of the plume by the geophysical techniques employed can lead to ambiguity, as an anomaly that does not correspond to contaminated areas appeared but to the presence of clays rich in electro-metallic components such as Mg, Fe, Mn and Al.


Asunto(s)
Monitoreo del Ambiente/métodos , Hidrocarburos/química , Contaminantes del Suelo/química , Geología , Hidrocarburos/análisis , Metales , Suelo , Contaminantes del Suelo/análisis , Tomografía
16.
Environ Monit Assess ; 192(2): 118, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31950287

RESUMEN

Analysis of elemental concentration in soil and water was carried out in Ortum to ensure safe utilization of soil and water resources for agriculture, industrial, and household purposes. Elemental analysis of soil and water was done using the EDXRF spectrometer and the inductively coupled plasma - optical emission spectrometry (ICP-OES), respectively. A total of 59 soil samples from different locations and depth and 10 water samples were collected from Ortum using purposive sampling method. The results of the mean elemental composition of 13 elements Ni (ppm), Cu (ppm), Zn (ppm), Pb (ppm), K (%w), Ca (%w), Fe (%w), Ti (%w), Mn (ppm), Rb (ppm), Sr (ppm), Zr (ppm), and Nb (ppm) in soils were 58.11, 46.91, 73.49, 22.20, 3.83, 24.39, 1.72, 7.73, 1529.74, 60.98, 442.26, 410.63, and 29.36, respectively, and the mean of 19 elements Ni, Cu, Pb, Zn, Ag, Al, As, Ba, Ca, Cd, Co, Cr, Fe, K, Mg, Mn, Mo, Na, and Se in water samples in (mg/l) were 0.037, 0.0014, 0.0005, 0.0042, 0.0030, 0.021, 0.0080, 0.12, 73.81, 0.00023, 0.0036, 0.00276, 0.0040, 6.11, 38.18, 0.00023, 0.0032, 46.87, and 0.0026, respectively. The average elemental concentration in soils was within the world average range. The mean concentration of Cu, Zn, and Pb in soil reduced with increase in depth while that of Ni increased with increase in depth. The average metal pollution indices in soils, geoaccumulation index (Igeo) potential ecological risk index (Ei), and synthesized potential ecological risk index (Er) were evaluated and found to be - 0.40, 4.92, and 19.69, respectively. According to the classification index, the results show that the soil in Ortum is moderately polluted, and the risk associated with the measured elemental concentration of Ni, Zn, Cu, and Pb in the soils is low. The elemental concentrations in water samples was lower than the recommended permissible limits except for Calcium (Ca) in borehole water with an average of 90.80 mg/l against the permissible levels of 75 mg/l (WHO, 2011). The pH for water samples was found to range from 6.60 to 7.71 with an average of 7.07 which is within the acceptable range of pH 6.5 to pH 8.5 as recommended by WHO, 2011. The study found out that elemental concentration in soil and water samples from Ortum were withing the world average values and that the soil and water in Ortum is safe for use in agriculture and domestic purposes.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Metales Pesados/análisis , Agricultura , Ecología , Contaminación Ambiental/análisis , Contaminación Ambiental/estadística & datos numéricos , Industrias , Kenia , Medición de Riesgo , Suelo/química , Contaminantes del Suelo/análisis
17.
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
18.
Environ Monit Assess ; 192(2): 124, 2020 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-31960198

RESUMEN

Investigation on the behavior of elements in the soil is important both in exploration and environmental geochemistry studies. Rare earth elements (REEs) are the most useful among all trace elements. REE studies have shown that they have important applications in igneous, sedimentary, and metamorphic petrology. This work aims to investigate the relationship of these elements with one another and the behavior of the major oxides and trace elements with REEs. Soil samples were obtained from the alteration site possibly related to mineralization and were analyzed for major oxides, trace elements, and REEs. The relationships between the major oxide-trace element/heavy metal and REE were investigated by statistical methods, such as descriptive statistics, correlation coefficient, and principle component analysis. According to the correlation coefficient matrix, light REEs (LREEs) showed weak to moderate negative correlation with MgO and MnO and moderately positive correlation with SiO2 and K2O. No association was detected between the heavy REEs (HREEs) and the main oxides, but a strong positive correlation with LREEs was observed. For the trace elements, LREE showed a weak positive correlation with Ba and Sn and moderate to strong positive correlation with As, Hf, Nb, Rb, Ta, Th, U, W, and Zr. They also displayed weak to moderate correlation with Sc, Co, Zn, Ni, and V. HREE showed weak to moderate positive correlation with Ni, Cs, Ga, Hf, Th, Zr, As, and LREE. Although REEs exhibited no direct correlation with Au and Ag, they showed a good correlation with some trace elements that are related to hydrothermally altered products. This study showed that REEs can also be used in exploration and environmental geochemistry studies by exploiting the relationship between REEs and other trace/heavy metal elements.


Asunto(s)
Metales de Tierras Raras/análisis , Contaminantes del Suelo/análisis , Oligoelementos/análisis , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Compuestos Orgánicos , Óxidos/análisis , Dióxido de Silicio/análisis , Suelo
19.
Chemosphere ; 242: 125255, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31896180

RESUMEN

A woody-biochar was added to waste biomass during a composting process. The resulting compost-char was amended to a metal contaminated soil and two plant species, L. perenne and E. sativa, were grown in a pot experiment to determine 1) plant survival and stress factors, 2) uptake of metals to plants and, 3) chemical characteristics of sampled soils and pore waters. Compost supplemented with biochar after the composting process were also tested, as well as a commercially available compost, for comparison. Co-composting with biochar hastened the composting process, resulting in a composite material of reduced odour, increased maturity, circum-neutral pH and increased moisture retention than compost (increase by 3% of easily removable water content). When amended to the soil, CaCl2 extractable and pore water metals s were reduced by all compost treatments with little influence of biochar addition at any tested dose. Plant growth success was promoted furthest by the addition of co-composted biochar to the test soil, especially in the case of E. sativa. For both tested plant species significant reductions in plant metal concentrations (e.g. 8-times for Zn) were achieved, against the control soil, by compost, regardless of biochar addition. The results of this study demonstrate that the addition of biochar into the composting process can hasten the stability of the resulting compost-char, with more favourable characteristics as a soil amendment/improver than compost alone. This appears achievable whilst also maintaining the provision of available nutrients to soils and the reduction of metal mobility, and improved conditions for plant establishment.


Asunto(s)
Brassicaceae/crecimiento & desarrollo , Carbón Orgánico/química , Compostaje , Lolium/crecimiento & desarrollo , Metales/análisis , Madera/química , Biodegradación Ambiental , Biomasa , Brassicaceae/química , Lolium/química , Modelos Teóricos , Suelo/química , Contaminantes del Suelo/análisis
20.
Chemosphere ; 242: 125281, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31896191

RESUMEN

In this study, the potential of pulverized waste tires (PWTs), either on their own or mixed with soil (well graded sand), to act as adsorptive fill materials was evaluated by conducting laboratory tests for accessing their adsorption and geotechnical properties. PWT (0, 5, 10, 15, 25, and 100 wt%) was mixed with soil to evaluate the removal of benzene, toluene, ethylbenzene, and xylene (BTEX) components and two heavy metal ions (Pb2+ and Cu2+). Adsorption batch tests were performed to determine the equilibrium sorption capacity of each mixture. Subsequently, compaction, direct shear, and consolidation tests were performed to establish their geotechnical properties. The results showed that BTEX had the strongest affinity based on the uptake capacity by the soil-PWT mixtures. The adsorption of BTEX increased for greater PWT content, with pure PWT having the highest adsorption capacity toward BTEX removal: uptake capacities for xylene, ethylbenzene, toluene, and benzene were 526, 377, 207 and 127 µg/g sorbent, respectively. Heavy metal removal was increased by increasing the amount of PWT up to 10 wt%, and then decreased beyond this ratio. Compacted soil-PWT mixtures comprising 5-25 wt% PWT have relatively low dry unit weight, low compressibility, adequate shear capacity for many load-bearing field applications, and satisfactory adsorption of organic/inorganic contaminants, such that they could also be used as adsorptive fill materials.


Asunto(s)
Derivados del Benceno/análisis , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Residuos Sólidos/análisis , Adsorción , Benceno/análisis , Modelos Teóricos , Eliminación de Residuos , República de Corea , Suelo/química , Tolueno/análisis , Xilenos/análisis
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