Is the toxic potential of nanosilver dependent on its size?

BackgroundNanosilver is one of the most commonly used engineered nanomaterials (ENMs). In our study we focused on assessing the size-dependence of the toxicity of nanosilver (Ag ENMs), utilising materials of three sizes (50, 80 and 200 nm) synthesized by the same method, with the same chemical composition, charge and coating.MethodsUptake and localisation (by Transmission Electron Microscopy), cell proliferation (Relative growth activity) and cytotoxic effects (Plating efficiency), inflammatory response (induction of IL-8 and MCP-1 by Enzyme linked immune sorbent assay), DNA damage (strand breaks and oxidised DNA lesions by the Comet assay) were all assessed in human lung carcinoma epithelial cells (A549), and the mutagenic potential of ENMs (Mammalian hprt gene mutation test) was assessed in V79-4 cells as per the OECD protocol. Detailed physico-chemical characterization of the ENMs was performed in water and in biological media as a prerequisite to assessment of their impacts on cells. To study the relationship between the surface area of the ENMs and the number of ENMs with the biological response observed, Ag ENMs concentrations were recalculated from μg/cm2 to ENMs cm2/cm2 and ENMs/cm2.ResultsStudied Ag ENMs are cytotoxic and cytostatic, and induced strand breaks, DNA oxidation, inflammation and gene mutations. Results expressed in mass unit [μg/cm2] suggested that the toxicity of Ag ENMs is size dependent with 50 nm being most toxic. However, re-calculation of Ag ENMs concentrations from mass unit to surface area and number of ENMs per cm2 highlighted that 200 nm Ag ENMs, are the most toxic. Results from hprt gene mutation assay showed that Ag ENMs 200 nm are the most mutagenic irrespective of the concentration unit expressed.ConclusionWe found that the toxicity of Ag ENMs is not always size dependent. Strong cytotoxic and genotoxic effects were observed in cells exposed to Ag ENMs 50 nm, but Ag ENMs 200 nm had the most mutagenic potential. Additionally, we showed that expression of concentrations of ENMs in mass units is not representative. Number of ENMs or surface area of ENMs (per cm2) seem more precise units with which to compare the toxicity of different ENMs.

[1]  David H. Chen,et al.  Genotoxicity of silver nanoparticles evaluated using the Ames test and in vitro micronucleus assay. , 2012, Mutation research.

[2]  Cui Tang,et al.  Effects of particle size and surface charge on cellular uptake and biodistribution of polymeric nanoparticles. , 2010, Biomaterials.

[3]  U. Vogel,et al.  Diesel exhaust particles are mutagenic in FE1-MutaMouse lung epithelial cells. , 2008, Mutation research.

[4]  K. Dawson,et al.  Time and space resolved uptake study of silica nanoparticles by human cells. , 2011, Molecular bioSystems.

[5]  Herman Autrup,et al.  Toxicity of silver nanoparticles - nanoparticle or silver ion? , 2012, Toxicology letters.

[6]  A. Collins,et al.  Oxidative damage to DNA: do we have a reliable biomarker? , 1996, Environmental health perspectives.

[7]  Michael V. Liga,et al.  Antimicrobial nanomaterials for water disinfection and microbial control: potential applications and implications. , 2008, Water research.

[8]  G. Pojana,et al.  Coating-dependent induction of cytotoxicity and genotoxicity of iron oxide nanoparticles , 2015, Nanotoxicology.

[9]  Andreas Luch,et al.  Mechanisms of Silver Nanoparticle Release, Transformation and Toxicity: A Critical Review of Current Knowledge and Recommendations for Future Studies and Applications , 2013, Materials.

[10]  W. D. de Jong,et al.  The effect of particle size on the cytotoxicity, inflammation, developmental toxicity and genotoxicity of silver nanoparticles. , 2011, Biomaterials.

[11]  I. Yu,et al.  Subchronic inhalation toxicity of silver nanoparticles. , 2009, Toxicological sciences : an official journal of the Society of Toxicology.

[12]  Kenneth A. Dawson,et al.  The need for in situ characterisation in nanosafety assessment: funded transnational access via the QNano research infrastructure , 2012, Nanotoxicology.

[13]  M. Hande,et al.  Cytotoxicity and genotoxicity of silver nanoparticles in human cells. , 2009, ACS nano.

[14]  Majid Montazer,et al.  A review on the application of inorganic nano-structured materials in the modification of textiles: focus on anti-microbial properties. , 2010, Colloids and surfaces. B, Biointerfaces.

[15]  Ha Ryong Kim,et al.  Appropriate In Vitro Methods for Genotoxicity Testing of Silver Nanoparticles , 2013, Environmental health and toxicology.

[16]  B. Sanderson,et al.  Cyto- and genotoxicity of ultrafine TiO2 particles in cultured human lymphoblastoid cells. , 2007, Mutation research.

[17]  Lennart Möller,et al.  Intracellular uptake and toxicity of Ag and CuO nanoparticles: a comparison between nanoparticles and their corresponding metal ions. , 2013, Small.

[18]  Jin Sik Kim,et al.  Twenty-eight-day oral toxicity, genotoxicity, and gender-related tissue distribution of silver nanoparticles in Sprague-Dawley rats. , 2008, Inhalation toxicology.

[19]  H. Autrup,et al.  Cytotoxicity and genotoxicity of silver nanoparticles in the human lung cancer cell line, A549 , 2011, Archives of Toxicology.

[20]  K. Dawson,et al.  Quantifying size-dependent interactions between fluorescently labeled polystyrene nanoparticles and mammalian cells , 2012, Journal of Nanobiotechnology.

[21]  H. Karlsson,et al.  Size-dependent toxicity of metal oxide particles--a comparison between nano- and micrometer size. , 2009, Toxicology letters.

[22]  S. G. Shankar,et al.  Effect of Nano-Silver on Cell Division and Mitotic Chromosomes : A Prefatory Siren , 2007 .

[23]  Rudolf Hagen,et al.  Silver nanoparticles: evaluation of DNA damage, toxicity and functional impairment in human mesenchymal stem cells. , 2011, Toxicology letters.

[24]  M. Shahedi,et al.  Evaluation of nanocomposite packaging containing Ag and ZnO on shelf life of fresh orange juice , 2010 .

[25]  Maria Dusinska,et al.  Can Standard Genotoxicity Tests be Applied to Nanoparticles? , 2012, Journal of toxicology and environmental health. Part A.

[26]  K. Dawson,et al.  Experimental and theoretical comparison of intracellular import of polymeric nanoparticles and small molecules: toward models of uptake kinetics. , 2011, Nanomedicine : nanotechnology, biology, and medicine.

[27]  Matthias Epple,et al.  TOXICITY OF SILVER NANOPARTICLES INCREASES DURING STORAGE BECAUSE OF SLOW DISSOLUTION UNDER RELEASE OF SILVER IONS , 2010 .

[28]  Joe Mari Maja,et al.  Applications of nanomaterials in agricultural production and crop protection: A review , 2012 .

[29]  Ibrahim Mohamed Hamouda Current perspectives of nanoparticles in medical and dental biomaterials , 2012, Journal of biomedical research.

[30]  Bengt Fadeel,et al.  Size-dependent cytotoxicity of silver nanoparticles in human lung cells: the role of cellular uptake, agglomeration and Ag release , 2014, Particle and Fibre Toxicology.

[31]  Xiaojian Wang,et al.  Mechanisms of PVP in the preparation of silver nanoparticles , 2005 .

[32]  Liping Tang,et al.  Nanomaterial cytotoxicity is composition, size, and cell type dependent , 2010, Particle and Fibre Toxicology.

[33]  Matthias Epple,et al.  Silver, gold, and alloyed silver–gold nanoparticles: characterization and comparative cell-biologic action , 2012, Journal of Nanoparticle Research.

[34]  T. Kumaravel,et al.  Characterization of synthesized silver nanoparticles and assessment of its genotoxicity potentials using the alkaline comet assay. , 2012, Mutation research.

[35]  Alexander M Seifalian,et al.  Nanosilver as a new generation of nanoproduct in biomedical applications. , 2010, Trends in biotechnology.

[36]  Robert N Grass,et al.  Exposure of engineered nanoparticles to human lung epithelial cells: influence of chemical composition and catalytic activity on oxidative stress. , 2007, Environmental science & technology.

[37]  Kyunghee Choi,et al.  Silver nanoparticles induce cytotoxicity by a Trojan-horse type mechanism. , 2010, Toxicology in vitro : an international journal published in association with BIBRA.

[38]  Albert Duschl,et al.  Shape matters: effects of silver nanospheres and wires on human alveolar epithelial cells , 2011, Particle and Fibre Toxicology.

[39]  G. Eggeler,et al.  Cell type-specific responses of peripheral blood mononuclear cells to silver nanoparticles. , 2011, Acta biomaterialia.

[40]  Vicki Stone,et al.  An in vitro liver model - assessing oxidative stress and genotoxicity following exposure of hepatocytes to a panel of engineered nanomaterials , 2012, Particle and Fibre Toxicology.

[41]  N. Miura,et al.  Cytotoxic effect and apoptosis induction by silver nanoparticles in HeLa cells. , 2009, Biochemical and biophysical research communications.

[42]  J. Cheon,et al.  Size dependent macrophage responses and toxicological effects of Ag nanoparticles. , 2011, Chemical communications.

[43]  Maria Dusinska,et al.  Mechanisms of genotoxicity. A review of in vitro and in vivo studies with engineered nanoparticles , 2014, Nanotoxicology.

[44]  Maria Dusinska,et al.  Impact of agglomeration and different dispersions of titanium dioxide nanoparticles on the human related in vitro cytotoxicity and genotoxicity. , 2012, Journal of environmental monitoring : JEM.

[45]  Bernd Nowack,et al.  120 years of nanosilver history: implications for policy makers. , 2011, Environmental science & technology.

[46]  Jae-Chun Ryu,et al.  Cytotoxicity and genotoxicity of nano-silver in mammalian cell lines , 2010, Molecular & Cellular Toxicology.

[47]  A. Collins,et al.  Oxidation of cellular DNA measured with the comet assay. , 2002, Methods in molecular biology.

[48]  Gunnar Brunborg,et al.  Cytotoxic and genotoxic effects of silver nanoparticles in testicular cells. , 2012, Toxicology.

[49]  J. Cadet,et al.  Oxidative damage to DNA , 1995 .

[50]  V. Puntes,et al.  Altered characteristics of silica nanoparticles in bovine and human serum: the importance of nanomaterial characterization prior to its toxicological evaluation , 2013, Particle and Fibre Toxicology.

[51]  I. Beverland,et al.  Intercomparison of five PM10 monitoring devices and the implications for exposure measurement in epidemiological research. , 2000, Journal of environmental monitoring : JEM.

[52]  R D Tyagi,et al.  Engineered nanoparticles in wastewater and wastewater sludge--evidence and impacts. , 2010, Waste management.

[53]  A. Ivask,et al.  Particle-Cell Contact Enhances Antibacterial Activity of Silver Nanoparticles , 2013, PloS one.

[54]  Jin Won Hyun,et al.  Silver nanoparticles induce oxidative cell damage in human liver cells through inhibition of reduced glutathione and induction of mitochondria-involved apoptosis. , 2011, Toxicology letters.

[55]  Maria Dusinska,et al.  Toxicological aspects for nanomaterial in humans. , 2013, Methods in molecular biology.

[56]  Anant Kumar Singh,et al.  Effect of Surface Coating on the Toxicity of Silver Nanomaterials on Human Skin Keratinocytes. , 2010, Chemical physics letters.

[57]  J. Fay,et al.  The role of surface chemistry on the toxicity of ag nanoparticles. , 2013, Small.

[58]  N. Gjerdet,et al.  Agglomeration and sedimentation of TiO2 nanoparticles in cell culture medium. , 2009, Colloids and surfaces. B, Biointerfaces.

[59]  Alke Petri-Fink,et al.  Effect of cell media on polymer coated superparamagnetic iron oxide nanoparticles (SPIONs): colloidal stability, cytotoxicity, and cellular uptake studies. , 2008, European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V.

[60]  Nicklas Raun Jacobsen,et al.  Increased mutant frequency by carbon black, but not quartz, in the lacZ and cII transgenes of muta™mouse lung epithelial cells , 2007, Environmental and molecular mutagenesis.

[61]  Georgios A Sotiriou,et al.  Engineering nanosilver as an antibacterial, biosensor and bioimaging material. , 2011, Current opinion in chemical engineering.

[62]  Maria Dusinska,et al.  Toxicity screenings of nanomaterials: challenges due to interference with assay processes and components of classic in vitro tests , 2015, Nanotoxicology.

[63]  J. Zink,et al.  Use of coated silver nanoparticles to understand the relationship of particle dissolution and bioavailability to cell and lung toxicological potential. , 2014, Small.

[64]  W. Liu,et al.  Impact of silver nanoparticles on human cells: Effect of particle size , 2010, Nanotoxicology.

[65]  Maria Dusinska,et al.  Iron oxide nanoparticle toxicity testing using high-throughput analysis and high-content imaging , 2015, Nanotoxicology.

[66]  E. Gálová,et al.  Gentiana asclepiadea exerts antioxidant activity and enhances DNA repair of hydrogen peroxide- and silver nanoparticles-induced DNA damage. , 2012, Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association.

[67]  G. Jenkins,et al.  In vitro genotoxicity testing strategy for nanomaterials and the adaptation of current OECD guidelines , 2012, Mutation research.

[68]  P. Schwarze,et al.  Silver nanoparticles induce premutagenic DNA oxidation that can be prevented by phytochemicals from Gentiana asclepiadea. , 2012, Mutagenesis.

[69]  Iseult Lynch,et al.  Serum heat inactivation affects protein corona composition and nanoparticle uptake. , 2010, Biomaterials.