Prediction of Zinc and Cadmium Phytoavailability Within a Contaminated Agricultural Site using DGT

2006 ◽  
Vol 3 (1) ◽  
pp. 61 ◽  
Author(s):  
Jean-Yves Cornu ◽  
Laurence Denaix
Keyword(s):  
Thin Films ◽  
Human Health ◽  
Metal Contamination ◽  
Predictive Tool ◽  
Metal Concentrations ◽  
Wide Range ◽  
Agricultural Site ◽  
Diffusive Gradients ◽  
Metal Phytoavailability ◽  
Cultivated Soils

Environmental Context.In some agricultural areas, soils are contaminated by trace elements. This contamination of cultivated soils may constitute a serious problem for human health through the accumulation of metals in the edible parts of crops. In order to assess the risk for human health associated with metal contamination of soil, we need to develop simple tools like Diffusive Gradients in Thin Films (DGT) for predicting crop metal accumulation. The present study focuses on an agricultural site contaminated with fallout from industrial dust and reveals that DGT could be a predictive tool of zinc accumulation in lettuce. Abstract.Risk assessment of metal contamination in cultivated soils needs to address metal phytoavailability. The technique of diffusive gradients in thin films (DGT) has been shown to be a promising tool to assess metal phytoavailability in a wide range of soils. The present study has examined the ability of the DGT method to predict metal phytoavailability within a contaminated agricultural site. Lettuce (Lactuva sativa cv Appia) was grown in nine metal-contaminated soils differing mainly by their pH. Metal concentrations (Zn, Cd) in plant shoots were compared with total soil metal concentrations and free ion metal concentrations in soil pore waters, and effective concentrations, CE, measured by DGT. Plant Zn concentrations were highly related to CE, suggesting DGT can be a sensitive tool able to assess Zn phytoavailability within mildly contaminated agricultural soils. Plant Cd concentrations were less closely related to CE, signifying that processes other than Cd re-supply from the solid phase may occur during soil–plant transfer of Cd.

scholarly journals Preliminary Investigation concerning Metals Bioavailability in Waters of Aries River Catchment by Using the Diffusive Gradients in Thin Films Technique

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Marin Senila ◽  
Erika Andrea Levei ◽  
Lacrimioara Ramona Senila ◽  
Marius Roman
Keyword(s):  
Thin Films ◽  
Preliminary Investigation ◽  
Low Flow ◽  
Metal Species ◽  
Dissolved Metals ◽  
Metal Concentrations ◽  
River Catchment ◽  
Mining Areas ◽  
Diffusive Gradients ◽  
Very High

The paper presents the metals content and bioavailability in waters of Aries River catchment, Romania. Concentration of labile dissolved metal species measured by diffusive gradients in thin films technique (DGT), metals in colloidal and in particulate phases, and also general physical-chemical indicators of water were determined. Very high total metal concentrations were found in the tributaries that drain the mining areas. However, the influence of the polluted tributaries on the Aries River water quality was moderate, as a consequence of the tributaries low flow rate compared with that of the Aries River. Using the DGT technique the bioavailable metals fractions expressed as % of total dissolved metals concentrations were found to be 28–88% for Cu, 43–72% for Zn, 73–85% for Fe, and 33–70% for Mn. Depending on the used method for dissolved metals determination the classification of waters according to quality classes may differ. Excluding the colloidal metal fractions, DGT measures only truly dissolved metal concentrations. In cases with very high metal contamination the differences between total dissolved and DGT-labile concentrations are unimportant for waters classification. However, where the metals concentration is near the thresholds values the determination method is very important.

scholarly journals Inorganic arsenic and iron(II) distributions in sediment porewaters investigated by a combined DGT–colourimetric DET technique

2012 ◽  
Vol 9 (1) ◽  
pp. 31 ◽  
Author(s):  
William W. Bennett ◽  
Peter R. Teasdale ◽  
David T. Welsh ◽  
Jared G. Panther ◽  
Ryan R. Stewart ◽  
...  
Keyword(s):  
Thin Films ◽  
Human Health ◽  
Inorganic Arsenic ◽  
Sediment Type ◽  
New Approach ◽  
In Situ Investigation ◽  
Wide Range ◽  
The Status ◽  
Sediment Porewaters

Environmental contextContamination of aquatic ecosystems with inorganic arsenic is a concern for both environmental and human health. Sediments are an important sink for dissolved arsenic, but they may also act as a source of arsenic because of human-induced changes in aquatic systems. This paper describes a new approach for investigating the status of inorganic arsenic in sediments, based on recent developments in diffusion-based sediment sampling techniques. AbstractA new approach for investigating the biogeochemistry of inorganic arsenic and iron(II) in freshwater, estuarine and marine sediments is reported. The recently developed Metsorb diffusive gradients in thin films (DGT) technique for the measurement of total inorganic arsenic and the colourimetric diffusive equilibration in thin films (DET) technique for the measurement of iron(II), were utilised in combination to determine co-located depth profiles of both solutes in sediment porewaters. DGT-measured porewater arsenic concentrations were typically less than 40 nM, whereas iron(II) concentrations reached up to 704 µM. Statistically significant (P < 0.0002) correlations between porewater arsenic and iron(II) profiles were observed (R > 0.92) in mesocosms of each sediment type. This approach to investigating arsenic and iron geochemistry in sediments allows the in-situ determination of arsenic and iron species at exactly the same location in the sediment at 3-mm resolution for arsenic and 1-mm resolution for iron(II). The technique was capable of detecting very low concentrations of arsenic, with a detection limit of 0.27 nM (0.02 µg L–1) for a 48-h deployment time. Porewater iron(II), which is often present over a wide range of concentrations, was detectable up to 2000 µM. This study shows the application of these recently developed DGT and DET techniques for the in-situ investigation of inorganic arsenic and iron biogeochemistry in sediments. This approach has the potential to enable simple, yet highly representative assessment of the biogeochemical status of arsenic and iron in a variety of natural sediments, including groundwater sediments where mobilised arsenic is responsible for significant human health risks.

scholarly journals Assessing risk to human health for heavy metal contamination from public point utility through ground dust: a case study in Nantong, China

2021 ◽  
Author(s):  
Yanping Wang ◽  
Peng Qian ◽  
Dongming Li ◽  
Haifeng Chen ◽  
Xiangqian Zhou
Keyword(s):  
Heavy Metal ◽  
Human Health ◽  
Ecological Risk ◽  
Metal Contamination ◽  
Heavy Metal Contamination ◽  
Public Utilities ◽  
Metal Concentrations ◽  
Heavy Metal Concentrations ◽  
Significant Enrichment ◽  
Cu And Zn

Abstract Heavy metal contamination in ground dust presents potential environmental and human health threats. However, the heavy metal contamination status of ground dust in the vicinity of public point utilities remain poorly explored. Therefore, this study has been designed to analyze the heavy metal contaminations in the ground dust collected monthly near a public bronze sculpture in an urban campus of Nantong, China, using geo-accumulation indexes (Igeo), enrichment factors (EF), potential ecological risk indexes (RI), and health risks (non-carcinogenic risks-HI and carcinogenic risks-CR). This study revealed that the maximum Cr, Cu, Mn, Ni, Pb, and Zn concentrations in ground dust samples were 156.2, 708.8, 869.8, 140.8, 180.5, and 1089.7 mg kg-1 respectively in which the mean Cu and Zn concentrations were 9 and 7 times higher than the background level in soil. Temporally speaking, for the majority of heavy metals (with the exception of Ni), the high concentration seasons tend to mainly be the summer and autumn, as indicated by the higher Xlf and SIRM values during those seasons. It was observed that Cu and Zn exhibited significant enrichment (EF = 11.7 and 8.4, respectively), moderate to strong pollution (Igeo = 2.4 and 2.0, respectively), and moderate and low potential ecological risks (Eir = 45.6 and 6.6, respectively). The non-carcinogenic risks which adults exposed to the heavy metal concentrations suffered were found to be insignificant. However, the carcinogenic risks related to Ni (1.3E-04) had exceeded the acceptable level. Based on the obtained PCA and correlation analysis, the heavy metal concentrations in the ground dust of urban campuses could be related to public utilities, traffic-related exhaust sources, and industrial activities. This study’s findings demonstrated that urban public utilities require increased attention due to their significant enrichment, ecological risk factors, and the significant carcinogenic risks to the population.

scholarly journals Monitoring of Heavy Metal Pollution in Water and Sediments at the Mid-Black Sea Region by Using Passive Sampling Method Diffusive Gradients in Thin Films

2021 ◽  
Vol 9 (6) ◽  
pp. 1076-1086
Author(s):  
Arife Şimşek ◽  
Şule Sancak ◽  
Gülfem Bakan
Keyword(s):  
Thin Films ◽  
Heavy Metals ◽  
Heavy Metal ◽  
Black Sea ◽  
Passive Sampling ◽  
Sampling Method ◽  
Grab Sampling ◽  
Metal Concentrations ◽  
Water And Sediment ◽  
Diffusive Gradients

Determining the potential bioavailability of heavy metals, evaluating according to adapted regulations is essential to efficiently conserve our coastal and estuarine waters. In this study, it is aimed to determine the industrial pollution and various other pollution sources that the Black Sea Basin is exposed to by using DGT (Diffusive Gradients in Thin Films) method and grab (manuel) sampling method in water and sediment and to evaluate the existing pollution according to quality standards. In Samsun, seasonal samples were collected from five different sampling stations, namely Akkiraz Stream, Hıdırellez Stream, Organized Industrial Zone (OIZ) Channel, Şabanoğlu Stream and Selyeri Stream, which are selected from Tekkeköy region where industry is intensively active. In order to determine the heavy metal content in both water and sediment samples, the DGT method was chosen for passive sampling and the grab sampling method was used for active sampling, and the efficiency of the methods was evaluated. According to the results of the study, the heavy metal concentration in grab sampling for water samples in descending order Al> Fe> Zn> Pb> Ni> Cu; In the samples taken with DGT, they are listed as Al> Fe> Zn> Cu> Ni> Pb. There were significant relationships between the total metal concentrations of sediment (Csed) and water (Csu) in grab sampling and metal concentrations sediment (Csed-DGT) and water (Csu-DGT) measured by DGT. It was found that the sensitivity and performance of sampling with DGT was 2-10 times higher compared to grab sampling. The high resolution in situ DGT technique for the assessment and management of the potential release risk of heavy metals at the water-sediment interface is a complementary method that contributes to the standard grab sampling method.

scholarly journals Risk assessment of eight metals and their mixtures to aquatic biota in sediments with diffusive gradients in thin films (DGT): a case study in Pearl River intertidal zone

2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Yang-Guang Gu
Keyword(s):  
Thin Films ◽  
Intertidal Zone ◽  
Sediment Toxicity ◽  
River Estuary ◽  
Pearl River ◽  
Aquatic Biota ◽  
Metal Concentrations ◽  
Metal Mixtures ◽  
Diffusive Gradients

Abstract Background The ecotoxicological risk posed by metals and their mixtures in sediments depends on their bioavailability. Many methods for evaluating the bioavailability of metals in sediments/soils are time-consuming and expensive, and frequently result in equivocal outcomes. The diffusive gradients in thin films (DGT) technique is a good measure of bioavailability for metals that can avoid the above drawbacks. Therefore, more effective approaches to this method should be developed that focus on metal bioavailability. No studies have been conducted using DGT to assess metal mixtures to aquatic biota in sediments. This study is therefore the first attempt to assess sediment toxicity of metals and their mixtures to aquatic biota based on the DGT technique. The intertidal zone of the Pearl River Estuary is selected as a case study. Results The bioavailable (DGT-labile) concentrations of metals range as follows (μg/L): Cd, 0.34–3.62; Pb, 1.35–1.92; Ni, 0.67–92.83; Cu, 0.74–10.30; Zn, 28.60–296.94; Co, 0.03–58.85; Fe, 7.23–4539.36; and Mn, 19.40–6626.83. The risk quotient (RQ), which is the ratio between the measured metal concentrations in the environment (MEC) and the predicted no-effect concentration (PNEC), is conducted to evaluate the single metal risk. The RQ based on summing up the MEC/PNEC ratios (RQMEC/PNEC) and the RQ based on sum of toxic units (RQSTU) are used to assess risk of metal mixture. TheRQ values of Cd, Pb, Ni, Cu, Zn, Fe, and Mn significantly exceed 1, indicating that the adverse effects of the metals are not negligible. Regarding the toxicity of metal mixtures, the values of RQMEC/PNEC and RQSTU are both between 62.45 and 743.48, revealing that the possible risk has already occurred in the study area. Conclusions The two methods of RQMEC/PNEC and RQSTU based on DGT-labile metal concentrations are effective and suitable to estimate the toxicity of metal mixtures in sediments.

Use of the diffusive gradients in thin films technique to evaluate (bio)available trace metal concentrations in river water

2007 ◽  
Vol 387 (6) ◽  
pp. 2239-2244 ◽  
Author(s):  
Pavel Diviš ◽  
Hana Dočekalová ◽  
Lukáš Brulík ◽  
Marek Pavliš ◽  
Petr Hekera
Keyword(s):  
Thin Films ◽  
Trace Metal ◽  
River Water ◽  
Metal Concentrations ◽  
Diffusive Gradients

Use of diffusive gradients in thin-films for studies of chemical speciation and bioavailability

2015 ◽  
Vol 12 (2) ◽  
pp. 85 ◽  
Author(s):  
Hao Zhang ◽  
William Davison
Keyword(s):  
Thin Films ◽  
Natural Waters ◽  
Chemical Speciation ◽  
Chemical Components ◽  
Measurement Tool ◽  
Response Curves ◽  
Predictive Tool ◽  
Environmental Chemical ◽  
Diffusive Gradients

Environmental context The health of aquatic organisms depends on the distribution of the dissolved forms of chemical components (speciation) and their rates of interaction (dynamics). This review documents and explains progress made using the dynamic technique of diffusive gradients in thin-films (DGT) to meet these challenges of measuring directly chemical speciation and associated dynamics in natural waters. The relevance of these measurements to uptake by biota of chemical forms in soils, sediments and water is discussed with reference to this expanding literature. Abstract This review assesses progress in studies of chemical speciation using diffusive gradients in thin-films (DGT) by examining the contributions made by key publications in the last 20 years. The theoretical appreciation of the dynamic solution components measured by DGT has provided an understanding of how DGT measures most metal complexes, but excludes most colloids. These findings strengthen the use of DGT as a monitoring tool and provide a framework for using DGT to obtain in situ kinetic information. Generally, the capabilities of DGT as an in situ perturbation and measurement tool have yet to be fully exploited. Studies that have used DGT to investigate processes relevant to bioavailability have blossomed in the last 10 years, especially for soils, as DGT mimics the diffusion limiting uptake conditions that, under some conditions, characterise uptake by plants. As relationships between element accumulated by DGT and in plants depend on the plant species, soils studied, and the element and its chemical form, DGT is not an infallible predictive tool. Rather its strength comes from providing information on the labile species in the system, whether water, soil or sediment. Recent studies have shown good relationships between measurements of metals in periphyton and by DGT, and unified dose response curves have been obtained for biota in sediments when they are based on DGT measurements. Both these cases suggest that alternative approaches to the established ‘free ion’ approach may be fruitful in these media and illustrate the growing use of DGT to investigate environmental chemical processes.

scholarly journals A Slot-Die Technique for the Preparation of Continuous, High-Area, Chitosan-Based Thin Films

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1566
Author(s):  
Oliver J. Pemble ◽  
Maria Bardosova ◽  
Ian M. Povey ◽  
Martyn E. Pemble
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
High Volume ◽  
Mechanical Anisotropy ◽  
Diverse Range ◽  
Direction Parallel ◽  
High Area ◽  
Wide Range ◽  
Slot Die ◽  
Potential Applications

Chitosan-based films have a diverse range of potential applications but are currently limited in terms of commercial use due to a lack of methods specifically designed to produce thin films in high volumes. To address this limitation directly, hydrogels prepared from chitosan, chitosan-tetraethoxy silane, also known as tetraethyl orthosilicate (TEOS) and chitosan-glutaraldehyde have been used to prepare continuous thin films using a slot-die technique which is described in detail. By way of preliminary analysis of the resulting films for comparison purposes with films made by other methods, the mechanical strength of the films produced was assessed. It was found that as expected, the hybrid films made with TEOS and glutaraldehyde both show a higher yield strength than the films made with chitosan alone. In all cases, the mechanical properties of the films were found to compare very favorably with similar measurements reported in the literature. In order to assess the possible influence of the direction in which the hydrogel passes through the slot-die on the mechanical properties of the films, testing was performed on plain chitosan samples cut in a direction parallel to the direction of travel and perpendicular to this direction. It was found that there was no evidence of any mechanical anisotropy induced by the slot die process. The examples presented here serve to illustrate how the slot-die approach may be used to create high-volume, high-area chitosan-based films cheaply and rapidly. It is suggested that an approach of the type described here may facilitate the use of chitosan-based films for a wide range of important applications.

scholarly journals Applicability of Honey on Silkworms (Bombyx mori) and Quality Improvement of Its Biomaterials

2021 ◽  
Vol 11 (10) ◽  
pp. 4613
Author(s):  
Gabriela-Maria Baci ◽  
Alexandra-Antonia Cucu ◽  
Adela Ramona Moise ◽  
Daniel Severus Dezmirean
Keyword(s):  
Quality Improvement ◽  
Bombyx Mori ◽  
Human Health ◽  
Recombinant Proteins ◽  
Therapeutic Agent ◽  
Life Sciences ◽  
Model Organism ◽  
Medical Field ◽  
Wide Range ◽  
Ancient Times

Since ancient times, honey has been considered one of the most illustrious and esteemed natural products. Honey plays two key roles; specifically, it is an appreciated nutritional product, and also exhibits a wide range of beneficial properties for human health as a therapeutic agent. Furthermore, it has been shown that honey has valuable effects on the biological and physiological features of mulberry silkworms (Bombyx mori). Bombyx mori exhibits importance not only for the economy, but it also serves as an important biotechnological bioreactor for the production of recombinant proteins that have a great impact in the medical field and beyond. It also represents an important model organism for life sciences. In view of the fact that silk fibroin serves as a natural biopolymer that displays high biocompatibility with human organisms and due to honey’s various and remarkable properties for human health, the two elements are currently used together in order to develop ideal biomaterials for a wide range of purposes. In this review, by discussing the applicability of honey on Bombyx mori and beyond, the importance of honey for life sciences and related fields is spotlighted.

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