Engineered Nanoparticles In Soils Research Articles

Impact on Some Soil Physical and Chemical Properties Caused by Metal and Metallic Oxide Engineered Nanoparticles: A Review.

In recent years, the release of metal and metallic oxide engineered nanoparticles (ENPs) into the environment has generated an increase in their accumulation in agricultural soils, which is a serious risk to the ecosystem and soil health. Here, we show the impact of ENPs on the physical and chemical properties of soils. A literature search was performed in the Scopus database using the keywords ENPs, plus soil physical properties or soil chemical properties, and elements availability. In general, we found that the presence of metal and metallic oxide ENPs in soils can increase hydraulic conductivity and soil porosity and reduce the distance between soil particles, as well as causing a variation in pH, cation exchange capacity (CEC), electrical conductivity (EC), redox potential (Eh), and soil organic matter (SOM) content. Furthermore, ENPs or the metal cations released from them in soils can interact with nutrients like phosphorus (P) forming complexes or precipitates, decreasing their bioavailability in the soil solution. The results depend on the soil properties and the doses, exposure duration, concentrations, and type of ENPs. Therefore, we suggest that particular attention should be paid to every kind of metal and metallic oxide ENPs deposited into the soil.

The co-occurrence of Zn-and Cu-based engineered nanoparticles in soils: The metal extractability vs. toxicity to Folsomia candida

The presence of engineered nanoparticles (ENPs) in soil gradually increases, among others due to the nano-agrochemicals application. So far, the co-existence of different ENPs in soil is poorly examined. Here, the metal extractability and toxicity of soils spiked (300 mg kg−1) singly and jointly with Zn- and Cu-based ENPs or metal salts were tested. The samples were aged for 1 and 90 days. The predicting available metal component of ENPs concentrations were determined by different methods including soil pore water collection and batch extractions with H2O, CaCl2 or DTPA. Survival and reproduction of Folsomia candida were also evaluated. The combined effect of ENPs on the extractability of metals was mainly found with DTPA characterized by the highest leaching capacity among the used extractants. In fresh soil, the mixtures of ENPs differentiated only DTPA-extractable Cu level, while aging resulted in changes in both Zn and Cu concentrations leached by CaCl2 or DTPA. However, the character of the combined effect was an ENPs- and soil type-dependent, whereas the mixtures of metal salts mostly provided higher Zn and Cu recovery than the individual compounds. The pattern of co-toxicity of metal-oxide ENPs was also time-dependent: the antagonistic and synergistic effect was observed in the samples after 1 and 90 days, respectively. However, the toxicity was weakly related with extractable concentrations in both single and joint treatment of metal compounds. The distinct joint effect patterns of ENPs imply the need for more in-depth investigation of mechanisms of activity of ENPs mixtures in soil.

Freeze-thaw cycles promote vertical migration of metal oxide nanoparticles in soils

Understanding the migration of engineered nanoparticles (ENPs) in soil is of great significance for evaluating the potential risks of ENPs to ecosystem. So far, their migration under freeze-thaw cycles (FTCs) has not been investigated. This study explored the impacts of FTCs on the migration of three commonly used ENPs, copper oxide (CuO-NPs), cerium oxide (CeO2-NPs), and zinc oxide (ZnO-NPs), in three types of soil. After 32 FTC cycles, the highest migration rate of ENPs was found in black soil due to its higher clay particle content. CeO2-NPs with low surface charge exhibited the highest mobility among three ENPs, which migrated to 9–11 cm layer with the concentration of 42.1 mg/kg in the black soil column. ZnO-NPs were less influenced by FTCs as they were adsorbed onto sand grains due to electrostatic interaction, which migrated to 3–5 cm layer with the concentration of 25.2 mg/kg in the black soil. Higher moisture contents (50% and 100%) resulted in increased migration depth of the ENPs in all soils. Lower freezing temperature (−25 °C) caused fragmentation of large soil particles and produced more clay colloids. FTCs promoted the movement of moisture, which penetrated the soil and thus facilitated the movement of ENPs by increasing the contents and movement of clay colloids. This work reveals the migration behavior of ENPs in soils in freeze-thaw period and provides insights into the fate and environmental risk of nanomaterial at middle and high latitudes.

Transcriptional and biochemical response of barley to co-exposure of metal-based nanoparticles

The aim of study was to assess the joint effects of engineered nanoparticles (ENPs) in soil-plant system. The single and binary mixtures of nano-ZnO and nano-CuO at dose of 300 mg kg−1 were added to soil. The combined treatments of metal salts were applied to evaluate nano-specific effects. The bioavailable fraction of Zn/Cu was extracted with CaCl2 or DTPA from soil after 1, 7, 30 days. The plant response regarding to metal content, enzyme activity (SOD, POD, CAT) and relative gene expression (Zn/Cu SOD, CAT, APX, GPX) to ENPs mixtures was determined. The extractable metal concentrations in soil under co-exposure of ENPs were lower than under single treatments. The opposite combined effect was noticed for metal salts. After 7 days, lower Zn content in leaves was measured after co-exposure of ENPs than nano-ZnO, whereas in older plants the tendency was opposite. The highest Cu content in leaves was noted under co-exposure of metal salts, other treatments provided the similar Cu content level. The activity of enzymes was dependent on their type, sources of metal, duration and type of exposure. APX gene expression was only affected by ENPs. The study shed light on the interactions of ENPs in soil and plant.

Effect of engineered nanoparticles on soil biota: Do they improve the soil quality and crop production or jeopardize them?

AbstractNanoscience and nanotechnology have been shown to have the capacity to help study, manipulation,design, and synthesis of new nano‐sized materials to manufacture new products with desirable features never seen before. The unique properties of materials at nanoscale opens an excellent possibility for nanotechnology to be used in soil environmental remediation, and water, and air decontamination. In crop management, nanomaterials are used to regulate the controlled release of nutrients, fertilizers, and pesticides. However, it is not only necessary to expose the positive effects by the application of the nanomaterials but also to demonstrate the impacts on soil and nontarget organisms (plants, mesofauna, macrofauna, and soil microbiota). In this context, pieces of evidence on the adverse effects of engineered nanoparticles (ENP) on the physicochemical and biological properties of soils are discussed in this paper. We have found a diversity of contradictory results. The summaries, findings, and conclusions of most of the investigations support the need to understand the biological or physicochemical transformation and transport of ENP in soil, and in the plant‐organism relationship. Better understanding regarding the soil biota coupled with the ecological ENP behavior could ensure the safe use of ENP. Nanomaterials can change the physicochemical and biological properties of the soils; consequently, long‐term in situ field trials are required, and meanwhile, land‐application of nanomaterials should be limited to scientific experiments to fill knowledge gaps to not jeopardize the global food production or the environment and worldwide human health.

The effect of pH and ageing on the fate of CuO and ZnO nanoparticles in soils

The objective of this study was to evaluate the fractionation of ZnO and CuO engineered nanoparticles (ENPs) in soils with a pH adjusted to 4.0, 6.5, and 9.0 after 1 day and 30 days of incubation. Based on the multi-stage extraction, 5 fractions of metals were determined. Moreover, the effect of ENPs on the activity of acid, neutral and alkaline phosphatase was determined. The results of the study revealed that pH had a dominant effect on the metal participation in soils. The levels of those fractions of metals differed between nano-ZnO and nano-CuO, which could have resulted from differences in the dissolution of the ENPs. After 1 day, the concentration of Zn2+ (0.02–7.4 mg L−1) was 10 times higher than that of Cu2+. The metal fractionation in soil treated with ENPs and metal salts may also confirm the role of ENP dissolution. The concentration of potentially bioavailable fraction of Zn increased with a drop in pH. At a 4 pH concentration of Zn in the treatment with nano-ZnO and ZnCl2 was at a similar level (42.1–45 mg kg−1), whereas the addition of nano-CuO resulted in a lower content of Cu (24.7 mg kg−1) than CuCl2 (36.5 mg kg−1). On the other hand, the concentration of fraction exchangeable of both metals in the alkaline soil did not exceed the level of 5.0 mg kg−1. Sample incubation time was especially important for metal participation in samples with a pH of 6.5. The greatest differentiation of metal fractionation between the soils was also noted at a pH of 6.5, which could also have been a result of other properties of the soils. The strong effect of pH on the lability of ENPs in soils confirmed a need to trace the fate of ENPs in extreme soil conditions as well as in changing environment.

MOBILITY OF CERIUM DIOXIDE NANOPARTICLES IN SOILS AT DIFFERENT EXPOSURE SCENARIOS

Nowadays, widespread application of engineered nanoparticles (ENPs) inevitably leads to their release into the environment. Soils are regarded as the ultimate sink for ENPs. The study on the mobility of ENPs in soils is important in the assessment of potential risks related to their toxicity. The behavior of ENPs depends not only on the parameters of soil, but also on the exposure scenarios, namely, the amount of ENPs trapped in soil. We studied the mobility of cerium dioxide nanoparticles (nCeO2) in soils at different exposure scenarios. The relationship between the mobility of nCeO2and their concentration in the soil within the range 1 – 1000 ìg/g is evaluated. It is shown that the mobility of nCeO2decreases with a decrease in their concentration in the soil and attains the minimum value when the concentration of nCeO2goes below 10 ìg/g. In relative units, only about 0.1 – 0.2% of nCeO2(in aforementioned concentration range) exhibit mobility and can migrate in the soil profile under saturated conditions. The lion’s share of nCeO2(about 99.8%) remains immobile in the soil. Evidently, the vertical transport of nCeO2in soil profile should depend on the volume of released suspensions. In the case of small or moderate wet deposition, nanoparticles will accumulate in upper soil horizons characterized with the highest biological activity and thus can affect the soil inhabitants (plant roots, earthworms, insects, microorganisms, etc.).

Behavior of cerium dioxide nanoparticles in chernozem soils at different exposure scenarios.

Nowadays, widespread application of engineered nanoparticles (ENPs) inevitably leads to their release into the environment. Soils are regarded as the ultimate sink for ENPs. The study on mobility of ENPs in soils is important in the assessment of potential risks related to their toxicity. The behavior of ENPs is dependent not only on parameters of soil but also on exposure scenarios, namely, the amount of ENPs trapped in soil. In the present work, the mobility of cerium dioxide nanoparticles (nCeO2) in soils at different exposure scenarios has been studied. The relationship between mobility of nCeO2 and their concentration in soil in the range from 1 to 1000 μg g-1 is evaluated. It is shown that the mobility of nCeO2 decreases with decreasing their concentration in soil and attains the minimum value at the concentration of nCeO2 below 10 μg g-1. In relative terms, only about 0.1-0.2% of nCeO2 at their concentration in soil 10-1000 μg g-1 are mobile and can migrate in soil profile under saturated conditions. The major portion of nCeO2 (about 99.8%) remains immobile in soil. Evidently, the vertical transport of nCeO2 in soil profile should depend on volume of released suspensions. In the case of small or moderate wet deposition, nanoparticles will accumulate in upper soil horizons, where biological activity is highest, and affect the soil inhabitants (plant roots, earthworms, insects, microorganisms, etc.).

Zinc, copper, or cerium accumulation from metal oxide nanoparticles or ions in sweet potato: Yield effects and projected dietary intake from consumption

The potential release of metal oxide engineered nanoparticles (ENP) into agricultural systems has created the need to evaluate the impact of these materials on crop yield and food safety. The study here grew sweet potato (Ipomoea batatas) to maturity in field microcosms using substrate amended with three concentrations (100, 500 or 1000 mg kg DW−1) of either nZnO, nCuO, or nCeO2 or equivalent amounts of Zn2+, Cu2+, or Ce4+. Adverse effects on tuber biomass were observed only for the highest concentration of Zn or Cu applied. Exposure to both forms of Ce had no adverse effect on yield and a slight positive benefit at higher concentrations on tuber diameter. The three metals accumulated in both the peel and flesh of the sweet potato tubers, with concentrations higher in the peel than the flesh for each element. For Zn, >70% of the metal was in the flesh and for Cu >50%. The peels retained 75–95% of Ce in the tubers. The projected dietary intake of each metal by seven age-mass classes from child to adult only exceeded the oral reference dose for chronic toxicity in a scenario where children consumed tubers grown at the highest metal concentration. The results throughout were generally not different between the ENP- and ionic-treatments, suggesting that the added ENPs underwent dissolution to release their component ions prior to accumulation. The results offer insight into the fate and impact of these ENPs in soils.

Bioavailability of Engineered Nanoparticles in Soil Systems

AbstractNanotechnologies form a field of research that is still emerging with major gaps in knowledge regarding the behavior and potential toxicological risks of engineered nanoparticles (ENPs) in soils. While most of the studies are conducted in porous media (quartz and glass beads) and culture media, less frequently are the studies carried out in natural soils. However, the complex interactions occurring in soils, mediated by both soil components and soil organisms, are essential in bioavailability processes. Therefore, this paper is intended to highlight particularly the bioavailability of ENPs in soils. The potential release pathways of ENPs to soils are described and are faced with a lack of specific regulation and definitive nomenclature. This paper reviews a number of studies regarding ENP toxicological bioavailability on microorganisms and microfauna, mesofauna, and macrofauna inhabiting the soil, as well as on soil-plant systems. The paper especially discusses ENP behavior in soils that affect EN...

Mobility of Functionalized Quantum Dots and a Model Polystyrene Nanoparticle in Saturated Quartz Sand and Loamy Sand

Quantum dots (QDs) are one example of engineered nanoparticles (ENPs) with demonstrated toxic effects. Yet, little is known about the behavior of QDs in the natural environment. This study assessed the transport of two commercial carboxylated QDs (CdTe and CdSe) and carboxylated polystyrene latex (nPL) as a model nanoparticle using saturated laboratory-scale columns. The influence of solution ionic strength (IS) and cation type (K(+) or Ca(2+)) on the transport potential of these ENPs was examined in two granular matrices - quartz sand and loamy sand. The retention of all three particles was generally low in the quartz sand columns within the range of studied IS (0.1-100 mM) for the monovalent salt (KCl). In contrast, the retention of the three ENPs in the quartz sand was significant in the presence of 10 mM Ca(2+). Moreover, ENP attachment efficiencies (α) were enhanced by at least 1 order of magnitude in columns packed with loamy sand (for IS between 0.1-10 mM KCl). Although all three ENPs used here are carboxylated, they differ in the type of surface coating (e.g., choice of polymers or polyelectrolytes). Regardless of the surface coatings, the three ENPs exhibit comparable mobility in the quartz sand. However, the ENPs demonstrate variable transport potential in loamy sand suggesting that differences in the binding affinities of surface-modified ENPs for specific soil constituents can play a key role in the fate of ENPs in soils.

Barley genetics — not only here for the beer

The aim of study was to assess the joint effects of engineered nanoparticles (ENPs) in soil-plant system. The single and binary mixtures of nano-ZnO and nano-CuO at dose of 300 mg kg−1 were added to soil. The combined treatments of metal salts were applied to evaluate nano-specific effects. The bioavailable fraction of Zn/Cu was extracted with CaCl2 or DTPA from soil after 1, 7, 30 days. The plant response regarding to metal content, enzyme activity (SOD, POD, CAT) and relative gene expression (Zn/Cu SOD, CAT, APX, GPX) to ENPs mixtures was determined. The extractable metal concentrations in soil under co-exposure of ENPs were lower than under single treatments. The opposite combined effect was noticed for metal salts. After 7 days, lower Zn content in leaves was measured after co-exposure of ENPs than nano-ZnO, whereas in older plants the tendency was opposite. The highest Cu content in leaves was noted under co-exposure of metal salts, other treatments provided the similar Cu content level. The activity of enzymes was dependent on their type, sources of metal, duration and type of exposure. APX gene expression was only affected by ENPs. The study shed light on the interactions of ENPs in soil and plant.