Role of Particle Size and Soil Type in Toxicity of Silver Nanoparticles to Earthworms
01 Mar 2011-Soil Science Society of America Journal (John Wiley & Sons, Ltd)-Vol. 75, Iss: 2, pp 365-377
TL;DR: In this paper, the earthworm Eisenia fetida was exposed to a range of concentrations of AgNO 3 and two polyvinylpyrolidone coated Ag NPs with different particle size distributions.
Abstract: Silver nanoparticles (NPs) are an emerging contaminant of concern due to their increased use. The earthworm Eisenia fetida was exposed to a range of concentrations of AgNO 3 and two polyvinylpyrolidone coated Ag NPs with different particle size distributions. They were exposed in two different soils: a naturally occurring sandy loam and a standardized artificial soil. The AgNO 3 significantly reduced E. fetida growth and reproduction at 7.41 ± 0.01 mg kg ―1 Ag in the sandy loam but only reproduction was affected at concentrations of 94.1 ± 3.2 mg kg ―1 in the artificial soil. In the artificial soil, significant (α = 0.05) reproductive toxicity was only observed in organisms exposed to the Ag NPs at concentrations approximately eight times higher than those at which the effects from ionic Ag were observed. Eisenia fetida exposed to either AgNO 3 or Ag NPs in the sandy loam accumulated significantly (α = 0.05) higher concentrations of Ag than those exposed in the artificial soil and had higher bioaccumulation factors. Earthworms exposed to AgNO 3 also accumulated significantly higher concentrations of Ag than those exposed to Ag NPs. No differences in toxicity were observed between the two size distributions. Extended x-ray absorption fine structure spectroscopy analysis of the soils indicated that the Ag was approximately 10 to 17% Ag(I), suggesting that Ag ions may be responsible for effects on growth and development caused by exposure to Ag NPs. Our results also suggest that soil type is a more important determinant of Ag accumulation from Ag NPs than particle size.
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TL;DR: The current understanding of toxicity of engineered nanoparticles to representatives of various trophic levels is summarized to highlight important challenges within the field of econanotoxicity, challenges that analytical chemists are expertly poised to address.
Abstract: While nanoparticles occur naturally in the environment and have been intentionally used for centuries, the production and use of engineered nanoparticles has seen a recent spike, which makes environmental release almost certain. Therefore, recent efforts to characterize the toxicity of engineered nanoparticles have focused on the environmental implications, including exploration of toxicity to organisms from wide-ranging parts of the ecosystem food webs. Herein, we summarize the current understanding of toxicity of engineered nanoparticles to representatives of various trophic levels, including bacteria, plants, and multicellular aquatic/terrestrial organisms, to highlight important challenges within the field of econanotoxicity, challenges that analytical chemists are expertly poised to address.
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446 citations
University of South Carolina1, Commonwealth Scientific and Industrial Research Organisation2, Rice University3, United States Geological Survey4, University of Plymouth5, University of Adelaide6, University of Florida7, Swiss Federal Institute of Aquatic Science and Technology8, École Polytechnique Fédérale de Lausanne9, ETH Zurich10
TL;DR: There is a developing consensus that NMs may pose a relatively low environmental risk, but because of uncertainty and lack of data in many areas, definitive conclusions cannot be drawn.
Abstract: The present review covers developments in studies of nanomaterials (NMs) in the environment since our much cited review in 2008. We discuss novel insights into fate and behavior, metrology, transformations, bioavailability, toxicity mechanisms, and environmental impacts, with a focus on terrestrial and aquatic systems. Overall, the findings were that: 1) despite substantial developments, critical gaps remain, in large part due to the lack of analytical, modeling, and field capabilities, and also due to the breadth and complexity of the area; 2) a key knowledge gap is the lack of data on environmental concentrations and dosimetry generally; 3) substantial evidence shows that there are nanospecific effects (different from the effects of both ions and larger particles) on the environment in terms of fate, bioavailability, and toxicity, but this is not consistent for all NMs, species, and relevant processes; 4) a paradigm is emerging that NMs are less toxic than equivalent dissolved materials but more toxic than the corresponding bulk materials; and 5) translation of incompletely understood science into regulation and policy continues to be challenging. There is a developing consensus that NMs may pose a relatively low environmental risk, but because of uncertainty and lack of data in many areas, definitive conclusions cannot be drawn. In addition, this emerging consensus will likely change rapidly with qualitative changes in the technology and increased future discharges. Environ Toxicol Chem 2018;37:2029-2063. © 2018 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.
401 citations
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392 citations
TL;DR: It will be prudent to observe judicious and targeted use of ENMs so as to minimize environmental release until a comprehensive environmental fate and effects assessment can be undertaken.
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367 citations
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TL;DR: The results indicate that the bactericidal properties of the nanoparticles are size dependent, since the only nanoparticles that present a direct interaction with the bacteria preferentially have a diameter of approximately 1-10 nm.
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TL;DR: The reduction of [Ag(NH(3))(2)](+) by maltose produced silver particles with a narrow size distribution with an average size of 25 nm, which showed high antimicrobial and bactericidal activity against Gram-positive and Gram-negative bacteria, including highly multiresistant strains such as methicillin-resistant Staphylococcus aureus.
Abstract: A one-step simple synthesis of silver colloid nanoparticles with controllable sizes is presented. In this synthesis, reduction of [Ag(NH3)2]+ complex cation by four saccharides was performed. Four saccharides were used: two monosaccharides (glucose and galactose) and two disaccharides (maltose and lactose). The syntheses performed at various ammonia concentrations (0.005−0.20 mol L-1) and pH conditions (11.5−13.0) produced a wide range of particle sizes (25−450 nm) with narrow size distributions, especially at the lowest ammonia concentrations. The average size, size distribution, morphology, and structure of particles were determined by dynamic light scattering (DLS), transmission electron microscopy (TEM), and UV/Visible absorption spectrophotometry. The influence of the saccharide structure (monosacharides versus disaccharides) on the size of silver particles is briefly discussed. The reduction of [Ag(NH3)2]+ by maltose produced silver particles with a narrow size distribution with an average size of ...
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