Use Of Nanosilver Research Articles

Dynamic responses of carbon metabolism of sediment microbial communities to Ag nanoparticles: Effects of the single and repeated exposure scenarios

The widespread use of nanosilver will inevitably lead to their release into aquatic environment, threating the health of freshwater ecosystem. The toxic effects of silver nanoparticles (AgNPs) on sediment microbial diversity, community composition, and functional enzyme activity are well established, while little is known about how sediment microbes dynamically respond to the stress of different AgNPs exposure scenarios. Herein, microcosm experiments were performed to investigate the impacts of repeated (1 mg/L, applied every 6 days for 10 times) and single (10 mg/L) exposure scenarios of AgNPs on the specific functions of sediment microbes (5–60 days). The carbon metabolism of sediment microbial communities was measured using BIOLOG ECO microplates, and carbon metabolic rate and functional diversity indices were calculated. Compared to control group, the maximum carbon source utilization capacity of the microbial community increased by 6.6 and 15.4 % in the single and repeated exposure group, respectively. And the metabolic rates of sediment microorganisms were significant increased by 6.1 % in the repeated exposure group, which suggested that repetitive low-dosing of AgNPs induce a larger alteration of both capacity and rate of microbial carbon metabolism. Notably, different AgNPs exposure scenarios resulted in a shift in the carbon source preference of the microorganisms. After exposure for 60 days, compared with the controls, the ability to utilize polymers was significantly increased by 51.5 and 21.7 % in the single and repeated exposure groups, respectively, and decreased by 33.7 and 10.5 % in the utilization of miscellaneous, both exhibiting significant differences (P < 0.05), implying that AgNPs exposure scenarios affected the microbial-mediated carbon cycling processes in sediment. These results highlight that different exposure scenarios of AgNPs have different effects on the carbon metabolism capacity of microbial communities, thus affecting the carbon cycling processes in which microorganisms are involved.

Antibiofilm Effect of Silver Nanoparticles in Changing the Biofilm-Related Gene Expression of Staphylococcus epidermidis.

Nowadays, antibiotic resistance is a major public health problem. Among staphylococci, infections caused by Staphylococcus epidermidis (S. epidermidis) are frequent and difficult to eradicate. This is due to its ability to form biofilm. Among the antibiotic substances, nanosilver is of particular interest. Based on this information, we decided to investigate the effect of nanosilver on the viability, biofilm formation and gene expression of the icaADBC operon and the icaR gene for biofilm and non-biofilm S. epidermidis strains. As we observed, the viability of all the tested strains decreased with the use of nanosilver at a concentration of 5 µg/mL. The ability to form biofilm also decreased with the use of nanosilver at a concentration of 3 µg/mL. Genetic expression of the icaADBC operon and the icaR gene varied depending on the ability of the strain to form biofilm. Low concentrations of nanosilver may cause increased biofilm production, however no such effect was observed with high concentrations. This confirms that the use of nanoparticles at an appropriately high dose in any future therapy is of utmost importance. Data from our publication confirm the antibacterial and antibiotic properties of nanosilver. This effect was observed phenotypically and also by levels of gene expression.

Cytotoxicity of lycopene-mediated silver nanoparticles in the embryonic development of zebrafish-An animal study.

Nano-silver (AgNP) has biological properties which are significant for consumer products, food technology, and medical applications (e.g., wound care products, implantable medical devices, in diagnosis, drug delivery, and imaging). Thus, the use of nano-silver is becoming more and more widespread in medicine. However, the effect of these AgNPs on zebrafish remains unclear. Whereas, lycopene, a fat-soluble carotenoid acts as a potent antioxidant has proved its major role in treating many oral health problems such as lichen planus, and periodontitis. Usage of these lycopene AgNPs would yield better results in wound healing. In this study, we investigated the cytotoxic effects of AgNPs on fibroblasts cells of humans.To investigate the toxic effects of the lycopene-mediated AgNPs on the zebrafish (Danio rerio) and to examine these effects on the embryonic development of the fetus of this species.In this study, zebrafish embryos were treated with AgNPs 0.5, 1, 2, 3, 4 or 5 L nanoparticles/ml for 24 to 96 h post fertilization.Our results showed that with the increasing concentration of nanoparticles, there was a very mild toxic effect. Less toxic effects were observed with 1μl.Our results show that exposure to silver nanoparticles is less toxic to embryonic zebrafish at lower concentrations. The results will contribute to the current understanding of the potential biotoxic effects of nanoparticles and will aid in the safety assessment and synthesis of silver oxide nanoparticles.

Detection, Identification and Size Distribution of Silver Nanoparticles (AgNPs) in Milk and Migration Study for Breast Milk Storage Bags.

The engineered silver nanoparticles (AgNPs) have been widely used in various food contact materials (FCMs) based on their antibacterial properties. This widespread use of nanosilver has, however, increased the risk of exposure of AgNPs to human due to their migration from FCMs causing a potential hazard present in foods. Therefore, it is important to establish a reliable and practical method for the detection of AgNPs in food matrices to support risk assessment on AgNPs exposure. Taking the examples of milk and AgNPs-containing breast milk storage bags, this study established an approach for size characterization and quantification of AgNPs in milk and evaluated the relevant silver migration, based on enzymatic digestion and the analysis by asymmetric flow field–flow fractionation (AF4) hyphenated with inductively coupled plasma mass spectrometry (ICP-MS) and single particle inductively coupled plasma mass spectrometry (SP-ICP-MS). No migration of AgNPs was found from breast milk storage bags under various simulated storage conditions as well as extreme scenarios. The suitability and reliability of this method were also validated by the determination of multiple parameters, including accuracy, repeatability, limit of detection (LOD), limit of quantification (LOQ), and recovery, for AF4-ICP-MS and SP-ICP-MS, respectively, with good and overall acceptable evaluation results obtained for all. The established and validated approach was demonstrated to be suitable for the characterization and quantitation of AgNPs in milk as well as the analysis of their migration from breast milk storage bags.

Silver nanoparticles – possible applications and threats

Silver is known for its biocidal properties. This metal has been used for decorations and food preservation since ancient times and has also been used in medicine. Silver foil has been used to cover wounds and burns. In addition, silver solutions were created to help fight the microorganisms responsible for causing infections, which helped the wound healing process. Currently, to increase and optimize the properties of silver, it is used on a nanometric scale. Nanosilver, due to its expanded spectrum of properties, is used in many economic sectors, including in the production of disinfectants and food films, as well as in animal farms. Nanoparticles are also the basis of nanomedicine action. Creating new drug complexes with nanosilver and modifying the medical materials used in implantology or dentistry allow the lives of many people to be saved every day. In addition, nanosilver particles are commonly used as a specific disinfectant in the production of hospital materials: dressings, bandages, surgical masks, hospital clothing and shoes, and equipment. With the growing use of nanosilver, there are concerns about its harmful effects on living organisms, because not all its mechanisms of action are known. As is well known, the dose determines the toxicity of a given substance; the case is similar for nanosilver. However, is the dose providing antibacterial and antifungal properties non-toxic to animals and humans? This review presents a summary of the scientific research showing the scope of nanosilver activity and the resulting threats.

Antioxidant, Antimicrobial and Antiviral Properties of Herbal Materials.

Recently, increasing public concern about hygiene has been driving many studies to investigate antimicrobial and antiviral agents. However, the use of any antimicrobial agents must be limited due to their possible toxic or harmful effects. In recent years, due to previous antibiotics’ lesser side effects, the use of herbal materials instead of synthetic or chemical drugs is increasing. Herbal materials are found in medicines. Herbs can be used in the form of plant extracts or as their active components. Furthermore, most of the world’s populations used herbal materials due to their strong antimicrobial properties and primary healthcare benefits. For example, herbs are an excellent material to replace nanosilver as an antibiotic and antiviral agent. The use of nanosilver involves an ROS-mediated mechanism that might lead to oxidative stress-related cancer, cytotoxicity, and heart diseases. Oxidative stress further leads to increased ROS production and also delays the cellular processes involved in wound healing. Therefore, existing antibiotic drugs can be replaced with biomaterials such as herbal medicine with high antimicrobial, antiviral, and antioxidant activity. This review paper highlights the antibacterial, antiviral, and radical scavenger (antioxidant) properties of herbal materials. Antimicrobial activity, radical scavenger ability, the potential for antimicrobial, antiviral, and anticancer agents, and efficacy in eliminating bacteria and viruses and scavenging free radicals in herbal materials are discussed in this review. The presented herbal antimicrobial agents in this review include clove, portulaca, tribulus, eryngium, cinnamon, turmeric, ginger, thyme, pennyroyal, mint, fennel, chamomile, burdock, eucalyptus, primrose, lemon balm, mallow, and garlic, which are all summarized.

Benefits of a Nanosilver Nasal Spray for Postoperative Care of Patients with Chronic Rhinosinusitis.

To explore tending to patients with chronic rhinosinusitis using a nanosilver compound. From February 2014 to August 2016, 112 surgical patients with chronic rhinosinusitis were randomly divided into an observation group and a control group. Patients in the observation group were given antibiotics, care to retain hemostasis, and other treatment after surgery. Patients in the observation group were administered treatment with bonbijing nano antibacterial water spray post-surgery. The progress of both groups recorded. Nanosilver is metallic silver of nanometer size. Nanosilver particles in the spray are approximately 25 nm in diameter, strongly inhibit growth of or kill dozens of pathogenic microorganisms, e.g., Escherichia coli. Postoperative pain in patients in the observation group was less than pain in the control group patients (p < 0.05). Symptom and sign scores in observation group patients were lower than scores in control group patients (p < 0.05). Incidence of adverse reactions and complications was also lower in observation group patients (p<0.05). Use of nanosilver for tending to patients with chronic rhinosinusitis after surgery can significantly improve clinical symptoms and signs, and reduce adverse reactions and complications.

Nanoparticle treatment of maize analyzed through the metatranscriptome: compromised nitrogen cycling, possible phytopathogen selection, and plant hormesis

BackgroundThe beneficial use of nanoparticle silver or nanosilver may be confounded when its potent antimicrobial properties impact non-target members of natural microbiomes such as those present in soil or the plant rhizosphere. Agricultural soils are a likely sink for nanosilver due to its presence in agrochemicals and land-applied biosolids, but a complete assessment of nanosilver’s effects on this environment is lacking because the impact on the natural soil microbiome is not known. In a study assessing the use of nanosilver for phytopathogen control with maize, we analyzed the metatranscriptome of the maize rhizosphere and observed multiple unintended effects of exposure to 100 mg kg−1 nanosilver in soil during a growth period of 117 days.ResultsWe found several unintended effects of nanosilver which could interfere with agricultural systems in the long term. Firstly, the archaea community was negatively impacted with a more than 30% decrease in relative abundance, and as such, their involvement in nitrogen cycling and specifically, nitrification, was compromised. Secondly, certain potentially phytopathogenic fungal groups showed significantly increased abundances, possibly due to the negative effects of nanosilver on bacteria exerting natural biocontrol against these fungi as indicated by negative interactions in a network analysis. Up to 5-fold increases in relative abundance have been observed for certain possibly phytopathogenic fungal genera. Lastly, nanosilver exposure also caused a direct physiological impact on maize as illustrated by increased transcript abundance of aquaporin and phytohormone genes, overall resulting in a stress level with the potential to yield hormetically stimulated plant root growth.ConclusionsThis study indicates the occurrence of significant unintended effects of nanosilver use on corn, which could turn out to be negative to crop productivity and ecosystem health in the long term. We therefore highlight the need to include the microbiome when assessing the risk associated with nano-enabled agriculture.8o2Ktf3WjN9uvowsG6Jw_6Video

Biological and anthropogenic predictors of metal concentration in the Eurasian otter, a sentinel of freshwater ecosystems

Toxic metals have been linked to a range of adverse health effects in freshwater organisms. However, for higher vertebrates, there is little understanding of the large-scale drivers of exposure. We quantified toxic metal/semi-metal concentrations in a sentinel freshwater top predator, the Eurasian otter (Lutra lutra), across England and Wales, and determined how this varied with key natural and anthropogenic factors. We related liver concentrations in 278 otters that died between 2006 and 2017 to habitat biogeochemistry, proximity to point source contamination and to biological characteristics (length, sex, condition). Evidence for any positive association with putative anthropogenic sources (mining, human population, known discharges) was weak or lacking in nearly all cases, with the exception of a positive association between lead and human population density. Despite concerns that burgeoning use of nanosilver in consumer products might increase silver concentrations in waste waters, there was no increase over time. Spatial variation in soil/sediment pH, precipitation, and soil calcium oxide are indicated as significant predictors of metal concentrations in otters (higher cadmium and silver in areas with lower pH and higher rainfall, and higher chromium and lead in areas of lower calcium oxide). Liver chromium and nickel concentrations declined significantly over time (Cr 0.030 ± 1.2 to 0.015 ± 1.3 μg/g dry weight, Ni 0.0038 ± 1.2 to 0.00068 ± 1.5 μg/g, between 2006–2009 and 2014–2017), but other metals showed no temporal change. Biotic associations were important, with age related accumulation indicated for mercury and cadmium (as well as interactions with body condition). Our results suggest that larger-scale geochemical and hydrological processes are important in determining metal exposure in otters, and we provide an indication of risk factors that may be of relevance for freshwater vertebrates in other countries with well-developed water pollution management.

Optical properties of sol-gel coatings containing silver nanoparticles

The technology of receiving the antireflective coating increasing efficiency of use of sunlight in various service conditions is described. Suspensions of nanodimensional silicon dioxide with tetraethoxysilane as a precursor were synthesized to solve the assigned task. The received suspensions were applied by a dipping method on glass samples followed by the coating formation on a surface of the substrates at various temperatures. As a result of a cure of the received samples under natural conditions transparent film of about 500 nanometers thick having very low strength properties on the surface of glass were formed. Heat treatment led to the improvement of strength of coatings in process with increase of temperature up to 600 °C. Exceeding of this temperature resulted in cracking of coatings. In the course of heat treatment higher than 300 °C formation of a coating was accompanied by the thermolysis of silver nitrate that was introduced into silicon dioxide suspension with a formation of silver particles which size was in the nanoscale distance limits according to the results of Auger electron spectroscopy. Presence of evenly distributed silver nanoparticles provided an antireflective effect to coatings which at visual observation found expression in the form of the interference phenomenon. The obtained data confirmed prospects of use of nanosilver as a component of coatings on the basis of silicon dioxide in order to confer the antireflective properties.

Nursing care of diabetic foot based on nanosilver antibacterial dressings

To investigate the control and prevention of diabetic foot infection with nano-silver antibacterial dressings and the difficulty of nursing. Sixty patients with diabetic foot, treated at our hospital between January 2017 to January 2018, were randomly assigned to intervention and control groups (n = 30 per group). Blood glucose was strictly controlled in both groups. After debridement, the ulcerated feet of the intervention and control groups were wrapped with nanosilver antibacterial and Vaseline dressings, respectively. The degree of pain and the severity and areas of ulcers were evaluated at the time of admission and after four weeks of treatment. The time required for ulcers to heal was assessed and the number of dressing changes were counted. The two groups were compared in terms of ease of care. Although treatment improved the Wagner grade in both groups, the improvement was significantly better in the intervention group than in the control group (P &lt; 0.05). Moreover, treatment reduced ulcerated areas in both groups, with significantly smaller ulcerated areas in the intervention group than in the control group (P &lt; 0.05). The intervention group had significantly lower visual analog scores (VAS) than the control group (P &lt; 0.05), although treatment lowered VAS in both groups. Ulcers healed significantly sooner and dressings were changed less frequently in the intervention group than in the control group (P &lt; 0.05). The nursing difficulty of the intervention group was significantly lower than that of the control group. Nanosilver antibacterial dressings can promote healing, reduce ulcerated areas, improve Wagner classification, and reduce the frequency of dressing changes in patients with diabetic foot ulcers. At the same time, the use of nano-silver can reduce the difficulty of patient care.

Актуальные аспекты применения химически синтезированных соединений наночастиц серебра в животноводстве и агрохимии

Рассмотрены сферы применения наночастиц (НЧ) серебра в сельском хозяйстве. Приведен обзор литературы, посвященной использованию соединений НЧ серебра в животноводстве при кормлении и лечении сельскохозяйственных животных. Рассмотрены основные направления внедрения наносеребра в практику при защите культурных растений и их возделывании. Авторы представляют свои основные результаты исследований в этой области. Препарат “Арговит”, созданный на основе НЧ серебра и поливинилпирролидона, снижает антибиотикочувствительность, адгезивную и антилизоцимную активности патогенов родов Enterococcus, Salmonella и Escherichia, которые определяют возникновение, развитие и проявление инфекционных болезней у животных. Обнаружено, что нанокомпозиты серебра, представляющие собой НЧ серебра, погруженные в матрицы из природного полисахарида (арабиногалактана) или гуминовых веществ, обладают антибактериальным эффектом к бактерии, вызывающей кольцевую гниль картофеля. При этом нанокомпозиты оказывают стимулирующее воздействие на растения картофеля in vitro. Представленные сведения подтверждают перспективность широкого применения НЧ серебра в сельском хозяйстве.

Quantification and spatial resolution of silver nanoparticles in cotton textiles by surface-enhanced Raman spectroscopy (SERS)

For its powerful antimicrobial properties, nanosilver is the most widely used nanoparticle in commercial odor-neutralizing and anti-infective textiles. However, the recent prevalent use of nanosilver has prompted concerns for the potential adverse human and environmental effects caused from the leaching of nanosilver during usage and laundering, necessitating innovative strategies in characterizing nanosilver on textile substrates. This study investigated the viability of surface-enhanced Raman spectroscopy (SERS) as an analytical method for the characterization and quantification of nanosilver (silver nanoparticles, 12.4 ± 5.1 nm) in cotton. Two indicators, iron (III) tris (dimethyldithiocarbamate) (ferbam) and rhodamine 6G (R6G) were used to compare how efficiently they bind onto nanosilver incorporated into cotton (nanosilver-cotton) and exhibit signature SERS responses. Comparing the SERS spectra of the two indicators, R6G was found to be more appropriate for nanosilver-cotton. The solvent system for R6G was important in enhancing the SERS intensity in the cotton medium – the intensity obtained from water was nearly threefold greater than those from methanol and the 50:50 mixture of water and methanol. A linear correlation (R2 = 0.9761) between the intensity at 1503 cm−1 of R6G and the concentration of nanosilver in cotton was developed and was validated by analyzing the washing stability of nanosilver-cotton fabrics through simulated laundering cycles. The technique was also successfully applied to spatially resolve the distribution and aggregation of nanosilver on textile fabrics by mapping a coffee-ring deposition produced by the surface application of nanosilver to textile samples of raw cotton, scoured raw cotton, and 50:50 and 80:20 blends of polyester-cotton. These results validate SERS as a rapid and facile tool for monitoring the dispersion and concentration of nanosilver on textiles after application and laundering.

3 - Effects of Nanosilver on Antioxidant and Xenobiotic Response Pathways in HEK293T Cells

Nanosilver (1-100 nm silver particles) has antimicrobial properties and is widely used in many commercial, engineering, and biomedical applications. The potential effects of direct nanosilver exposure to human cells and other organisms through consumer products is largely unknown. Due to the increased use of nanosilver in these products, exposure to this nanomaterial is of concern. Thus, it is crucial to understand the potential biological effects and mechanistic perturbations caused by nanosilver at the cellular level. Nanosilver contributes to the production of reactive oxygen species (ROS) and, through the binding of nanosilver to thiol groups, causes depletion of the major cellular antioxidant molecule glutathione. This research examines the relative induction of the two primary detoxification pathways upon exposure to nanosilver. The first pathway involves the aryl hydrocarbon receptor (AhR) which induces various cytochrome P450 enzymes through xenobiotic response elements (XREs). The second pathway involves the nuclear factor-erythroid 2 like factors, which induce various xenobiotic-metabolizing and antioxidant enzymes through the electrophile response element/antioxidant response element (EpRE/ARE). Luciferase reporter assays indicate that nanosilver treatment induces activation of the ARE detoxification pathway through nuclear respiratory factor 2 (Nrf 2), as opposed to nuclear respiratory factor 1 (Nrf1), while suppressing the XRE detoxification pathway through the AhR. Additionally, nanosilver treatments do not change Nrf 2, Nrf 1, or AhR protein levels, indicating that other control mechanisms are involved. These results suggest that nanosilver exposure affects both ARE and XRE detoxification pathways. This research provides new information and insight into the mechanisms and pathways affected by nanosilver on the cellular level.

Nano-silver stabilized Pickering emulsions and their antimicrobial electrospun fibrous matrices

Efficacy of nano-silver for its antimicrobial properties is proven and a significant academic and industrial research has been devoted on use of nano-silver in applications including filtration, textiles, biomedical and others. In present work, in situ synthesized nano-silver was used as a Pickering stabilizer for water-in-oil emulsion of poly(ε-caprolactone) (PCL) which upon electrospinning led to formation of nano-silver containing fibrous matrix suitable as wound dressing. Nano-silver was synthetized in high yield using silver nitrate (AgNO3) as precursor and two different reductants viz. sodium borohydride (NaBH4) and poly(ethylene oxide) (PEO) in aqueous media which formed the dispersed phase of the emulsion. PCL solution in toluene comprised the continuous phase. Concentration of AgNO3 and PCL was varied to study the effect on emulsion’s stability. Nano-silver formed using PEO as reducing agent led to formation of highly stable emulsions in comparison to those formed using NaBH4. Emulsions thus produced were reproducibly electrospun to generate uniform fibrous matrices of desired fiber fineness. Nano-silver containing PCL matrices were assessed for their role as wound dressing by examining the antimicrobial properties.

Cytotoxic effects of nanosilver are highly dependent on the chloride concentration and the presence of organic compounds in the cell culture media

BackgroundNanosilver shows great promise for use in industrial, consumer or medical products because of its antimicrobial properties. However, the underlying mechanisms of the effects of silver nanoparticles on human cells are still controversial. Therefore, in the present study the influence of the chloride concentration and different serum content of culture media on the cytotoxic effects of nanosilver was systematically evaluated.ResultsOur results show that nanosilver toxicity was strongly affected by the composition of the culture media. The chloride concentration, as well as the carbon content affected the silver agglomeration and the complex formation. But also the dissolution of nanosilver and the availability of free silver ions (Ag+) were severely affected by the compositions of the culture media. Cells, only exposed to silver particles in suspension and dissolved silver complexes, did not show any effects under all conditions. Nanosilver agglomerates and silver complexes were not very soluble. Thus, cells growing on the bottom of the culture dishes were exposed to sedimented nanosilver agglomerates and precipitated silver complexes. Locally, the concentration of silver on the cell surface was very high, much higher compared the silver concentration in the bulk solution. The cytotoxic effects of nanosilver are therefore a combination of precipitated silver complexes and organic silver compounds rather than free silver ions.ConclusionsSilver coatings are used in health care products due to their bacteriostatic or antibacterial properties. The assessment of the toxicity of a certain compound is mostly done using in vitro assays. Therefore, cytotoxicity studies of nanosilver using human cell cultures have to be undertaken under well controlled and understood cultivations conditions in order to improve the compatibility of different studies. Especially when eukaryotic versus prokaryotic systems are compared for the evaluation of the use of nanosilver as antibacterial coatings for implants in order to prevent bacterial colonization.

Profiling of the toxicity mechanisms of coated and uncoated silver nanoparticles to yeast Saccharomyces cerevisiae BY4741 using a set of its 9 single-gene deletion mutants defective in oxidative stress response, cell wall or membrane integrity and endocytosis

The widespread use of nanosilver in various antibacterial, antifungal, and antiviral products warrants the studies of the toxicity pathways of nanosilver-enabled materials toward microbes and viruses. We profiled the toxicity mechanisms of uncoated, casein-coated, and polyvinylpyrrolidone-coated silver nanoparticles (AgNPs) using Saccharomyces cerevisiae wild-type (wt) and its 9 single-gene deletion mutants defective in oxidative stress (OS) defense, cell wall/membrane integrity, and endocytosis. The 48-h growth inhibition assay in organic-rich growth medium and 24-h cell viability assay in deionized (DI) water were applied whereas AgNO3, H2O2, and SDS served as positive controls. Both coated AgNPs (primary size 8–12nm) were significantly more toxic than the uncoated (~85nm) AgNPs. All studied AgNPs were ~30 times more toxic if exposed to yeast cells in DI water than in the rich growth medium: the IC50 based on nominal concentration of AgNPs in the growth inhibition test ranged from 77 to 576mg Ag/L and in the cell viability test from 2.7 to 18.7mg Ag/L, respectively. Confocal microscopy showed that wt but not endocytosis mutant (end3Δ) internalized AgNPs. Comparison of toxicity patterns of wt and mutant strains defective in OS defense and membrane integrity revealed that the toxicity of the studied AgNPs to S. cerevisiae was not caused by the OS or cell wall/membrane permeabilization.

Leaching potential of silver from nanosilver-treated textile products.

The use of nanosilver as an antibacterial agent for various products has increased, especially so, in textiles. This study aims to investigate the potential of Ag to leach from commercial products which contain nano-Ag by using the toxicity characteristic leaching procedure (TCLP) test in accordance with USEPA method 1311. Eight nano-Ag products were purchased from the market. Only those products that are likely to be disposed of in a landfill after end use were selected. Nano-Ag fabrics of different concentrations were also prepared at the laboratory scale, and the TCLP test was performed on them as well. The current study assumes that the new products were discarded without use. The Ag content was quantified by inductively coupled plasma-mass spectroscopy (ICP-MS) and ranged from 0.95 to 2.82μg/g of the product in the commercial products and from 1.49 to 350μg/g of the product in the lab-prepared fabrics. In the TCLP test results, Ag concentrations ranged from 4.3 to 64.9μg/L in the commercial products and from 28.9 to 28,381μg/L in the lab-prepared fabrics. The results also indicate that the amount of Ag released depends on the type of the fabrics. Additionally, the size of the nano-Ag released in percentage is different for each prepared fabric. This study can help in understanding the amount of Ag released during the disposal phase of a product in a landfill.

Silver Nanoparticles in Cosmetics

This review is presented as a common interest in silver nanoparticles, their origin, activity, and toxicity in cosmetic. The application of nanotechnology and nanomaterials can be found in many cosmetic products including moisturizer, hair care products, makeup and sunscreen. Nanomaterials are now being used in leading cosmetics products, most commonly as chemicals used to give the protection. A silver nanoparticle is the potent and broad spectrum antimicrobial agent. This review paper looks into use of nano silver and provides an overview of current activity in this area.

DPSIR and Stakeholder Analysis of the Use of Nanosilver

First concerns about the use of nanosilver were raised almost a decade ago, but assessing the risks has been extremely challenging scientifically, and regulation to protect environmental and human health remains controversial. In order to understand the known risks and issues associated with the use of nanosilver, we carried out a DPSIR analysis and analysed drivers, pressures, state, impacts and potential policy responses. We found that most concerns relate to the potential development of multi-resistant bacteria and the environmental impacts of nanosilver. From the DPSIR analysis, we found that new (separate) legislation for nanomaterials in general and nanosilver-specific changes in the current European chemical, biocide and medical legislation were the optimal policy responses, along with limiting the overall use of nanosilver. In order to qualify the identified potential policy responses, we carried out a stakeholder analysis, in order to explore possibilities for reaching consensus amongst stakeholders. Through the stakeholder analysis, the interests, views, power and influence of the identified stakeholders were mapped. Overall, the policy options identified in the DPSIR analysis were deemed not to be implementable, as industry and NGOs seem to have fundamentally conflicting views and interests. The use of the combination of DPSIR and stakeholder analysis proved valuable for use in cases of complexity, as they compensate for each other’s limitations and open up for a discussion what can be done to reduce risks.