Reviews of the toxicity behavior of five potential engineered nanomaterials (ENMs) into the aquatic ecosystem (original) (raw)
Related papers
2020
Nanotechnology is defined as the design, characterisation, production and application of structures, devices and systems controlling shape, size and composition at the nanoscale (1 to 100 nm). At this scale, nanomaterials (NM) hold specific properties that potentiate its wide and efficient use in several areas of research, industry, technology and consumer products. However, today it is recognized that those same properties of NM may raise new challenges in the safety, regulatory or ethical domains. The explosive growing use of NM in consumer products suggests that they are already being released into the environment, namely to aquatic ecosystems, where they may pose adverse effects to biota. As they exhibit different properties from their bulk counterparts, namely a higher surface:volume ratio that increases its reactivity, it is necessary to generate novel data for these emergent materials regarding its ecotoxicity to biota, and how it is influenced by several environmental factors. According, the present work aimed at understanding the influence of several parameters on the toxicity of inorganic and organic NM to biota
A Comprehensive Review on the Aquatic Toxicity of Engineered Nanomaterials
Reviews in Nanoscience and Nanotechnology, 2013
As engineered nanomaterials (NMs) are continually introduced into commercial markets, some of them may be eventually released into the aquatic environment during their product life-cycles. This article aims to provide a comprehensive review on the processes which ultimately govern the toxicity of NMs to aquatic organisms. Firstly, their potential entry routes into aquatic ecosystems are identified. Ambient conditions which affect their behavior (i.e., aggregation, sedimentation, dissolution, adsorption, stabilization, degradation and concentration in surface microlayer) and hence alter their characteristics in aqueous medium are also acknowledged. Issues regarding difficulties in their characterization in complex environmental matrices are therefore explicitly considered, while recent efforts to quantify or estimate their concentrations are summarized. Uptake pathways of NMs by aquatic organisms from the water column, sediments and diets are traced, and the resultant toxic mechanisms of four chosen NMs (i.e., nano titanium dioxide (nTiO 2), nano zinc oxide (nZnO), nano silver (nAg) and buckminsterfullerene (C 60)) within the organisms (i.e., algae and bacteria, crustaceans, bivalves and fish) are discussed. Environmental modulations on their toxicities are brought into the picture for further elucidation on their effects. Finally, knowledge gaps are gathered from contemporary studies on aquatic toxicology of NMs, and recommendations are made regarding such investigations in an attempt to improve their clarity, practicality and ecological relevancy.
Nanomaterials
Rapid commercialisation of nano-enabled products (NEPs) elevates the potential environmental release of engineered nanomaterials (ENMs) along the product life cycle. The current review examined the state of the art literature on aquatic environment exposure and ecotoxicity of product released (PR) engineered nanomaterials (PR–ENMs). Additionally, the data obtained were applied to estimate the risk posed by PR–ENMs to various trophic levels of aquatic biota as a means of identifying priority NEPs cases that may require attention with regards to examining environmental implications. Overall, the PR–ENMs are predominantly associated with the matrix of the respective NEPs, a factor that often hinders proper isolation of nano-driven toxicity effects. Nevertheless, some studies have attributed the toxicity basis of observed adverse effects to a combination of the released ions, ENMs and other components of NEPs. Notwithstanding the limitation of current ecotoxicology data limitations, the...
A comprehensive assessment of the environmental risks posed by engineered nanomaterials (ENMs) entering the environment is necessary, due in part to the recent predictions of ENM release quantities and because ENMs have been identified in waste leachate. The technical complexity of measuring ENM fate and transport processes in all environments necessitates identifying trends in ENM processes. Emerging information on the environmental fate and toxicity of many ENMs was collected to provide a better understanding of their environmental implications. Little research has been conducted on the fate of ENMs in the atmosphere; however, most studies indicate that ENMs will in general have limited transport in the atmosphere due to rapid settling. Studies of ENM fate in realistic aquatic media indicates that in general, ENMs are more stable in freshwater and stormwater than in seawater or groundwater, suggesting that transport may be higher in freshwater than in seawater. ENMs in saline waters generally sediment out over the course of hours to days, leading to likely accumulation in sediments. Dissolution is significant for specific ENMs (e.g., Ag, ZnO, copper ENMs, nano zero-valent iron), which can result in their transformation from nanoparticles to ions, but the metal ions pose their own toxicity concerns. In soil, the fate of ENMs is strongly dependent on the size of the ENM aggregates, groundwater chemistry, as well as the pore size and soil particle size. Most groundwater studies have focused on unfavorable deposition conditions, but that is unlikely to be the case in many natural groundwaters with significant ionic strength due to hardness or salinity. While much still needs to be better understood, emerging patterns with regards to ENM fate, transport, and exposure combined with emerging information on toxicity indicate that risk is low for most ENMs, though current exposure estimates compared with current data on toxicity indicates that at current production and release levels, exposure to Ag, nZVI, and ZnO may cause toxicity to freshwater and marine species.
Critical Reviews in Environmental Science and Technology, 2020
The rapid development in nanotechnology and incorporation of engineered nano-particles (ENPs) in a wide range of consumer products releasing the massive quantities of ENPs in different environmental compartments. The released ENPs from nanoenabled products during their life cycle raising environmental health and safety issues. This review addresses the recent state of knowledge regarding the ENPs ecotoxicity to various organisms lying at different trophic levels. Studies show that reactive oxygen species (ROS) mediated oxidative stress is the primary mechanism of nano-toxicity, either through physical damage by direct contact or release of toxic ions after ENPs dissolution process. Moreover, ENPs uptake, transformation and toxicity on physiomorphological, biochemical and molecular levels in primary producers of terrestrial environment (plants) were also reviewed. Additionally, the intrinsic detoxification mechanism in plants in response to ENPs accumulation was also examined. In the end different sustainable approaches such as biogenic synthesis, clay minerals role, biochar application, bioremediation, and legislative measures are proposed for effective handling and treatment of nano-wastes to get the maximum benefits of nanotechnology with minimum negative outcomes.
Ecotoxicity of selected nano-materials to aquatic organisms
Environmental Toxicology, 2008
Present knowledge concerning the ecotoxic effects of nano-materials is very limited and merits to be documented more fully. For this purpose, we appraised the toxicity of nine metallic nanopowders (copper zinc iron oxide, nickel zinc iron oxide, yttrium iron oxide, titanium dioxide, strontium ferrite, indium tin oxide, samarium oxide, erbium oxide, and holmium oxide) and of two organic nanopowders (fullerene-C60 and single-walled carbon nanotube or SWCNT). After a simple process where nano-powders (NPs) were prepared in aqueous solution and filtered, they were then bioassayed across several taxonomic groups including decomposers (bacteria), primary producers (micro-algae), as well as primary and secondary consumers (micro-invertebrates and fish). Toxicity data generated on the 11 NPs reflected a wide spectrum of sensitivity that was biological level-, test-, and endpoint-specific. With all acute and chronic tests confounded for these 11 NPs, toxicity responses spanned over three orders of magnitude: [463 mg/L (24 h LC50 of the invertebrate Thamnoplatyurus platyurus for fullerene-C60) 7 0.3 mg/L (96 h EC50 of the invertebrate Hydra attenuata for indium tin oxide), that is a ratio of 1543. On the basis of the MARA (Microbial Array for Risk Assessment) assay toxic fingerprint concept, it is intimated that NPs may have different modes of toxic action. When mixed in a 1:1 ratio with a certified reference material (CRM) sediment, two solid phase assays and an elutriate assay, respectively, showed that five NPs (copper zinc iron oxide, samarium oxide, erbium oxide, holmium oxide, and SWCNT) were able to increase both CRM sediment toxicity and its elutriate toxicity. This initial investigation suggests that chemicals emerging from nanotechnology may pose a risk to aquatic life in water column and sediment compartments and that further studies on their adverse effects are to be encouraged. # 2008 Wiley Periodicals, Inc. Environ Toxicol 23: 591-598, 2008.
Environmental Toxicology and Chemistry, 2016
The US-EU Community of Research (CoR) was established in 2012 to provide a platform for scientists to develop a 'shared repertoire of protocols and methods to overcome nanotechnology environmental health and safety (nanoEHS) research gaps and barriers' (www.us-eu.org/). Based on work within the Ecotoxicology CoR (2012-2015) we provide here an overview of the state-of-theart of nanomaterials (NMs) in the aquatic environment by addressing different research questions with a focus on ecotoxicological test systems and the challenges faced when assessing nanomaterial (NM) hazards (e.g., uptake routes, bioaccumulation, toxicity, test protocols and model organisms). Our recommendation is to place particular importance on studying the ecological effects of aged/weathered NMs, as-manufactured NMs, as well as NMs released from consumer products in addressing the following overarching research topics: i) NM characterization and quantification in environmental and biological matrices, ii) NM transformation in the environment and consequences for bioavailability and toxicity, iii) alternative methods to assess exposure, iv) influence of exposure scenarios on bioavailability and toxicity, v) development of more environmentally realistic bioassays and vi) uptake, internal distribution, and depuration of NMs. Research addressing these key topics will reduce uncertainty in ecological risk assessment and support the sustainable development of nanotechnology.
Bioavailability, Toxicity, and Fate of Manufactured Nanomaterials in Terrestrial Ecosystems
Advances in Agronomy, 2014
The use of manufactured nanomaterials (MNMs) in consumer products has increased steadily over the past decade. MNMs from these consumer products are being discharged into waste streams and subsequently entering terrestrial ecosystems, primarily via land application of biosolids. As a result, the concentrations of MNMs in terrestrial ecosystems are increasing exponentially. Despite this, the majority of research investigating the bioavailability, fate, and effects of MNMs has focused on aquatic ecosystems. We review the current state of the knowledge on the fate of MNMs in terrestrial ecosystems as well as their effects on critical terrestrial ecoreceptors, including plants, bacteria, fungi, and soil invertebrates. While research on the bioavailability, toxicity, and ultimate fate of MNMs in terrestrial ecosystems is in its infancy, we conclude that there are critical knowledge gaps and an incomplete picture is emerging, with many studies reporting contradictory results. We also conclude that major discrepancies in the literature are primarily related to methodological and experimental shortcomings, such as inadequate MNM characterization, lack of consideration of MNM aggregation or dissolution, lack of proper controls, or the use of environmentally irrelevant MNM concentrations and/or exposure conditions. However, it is now evident that, under certain circumstances, MNMs are bioavailable and toxic to several key terrestrial ecoreceptors. It is also evident that additional systematic research focusing on the most environmentally relevant MNMs, including MNM transformation products and exposure conditions, is required to assess the risks posed to terrestrial ecosystems by nanotechnology.
Ecotoxicity and Toxicity of Nanomaterials with Potential for Wastewater Treatment Applications
Nanotechnology holds the promise of develop new processes for wastewater treatment. However, it is important to understand what the possible impacts on the environment of NMs. This study joins all the information available about the toxicity and ecotoxicity of NMs to human cell lines and to terrestrial and aquatic biota. Terrestrial species seems more protected, since effects are being recorded for concentrations higher than those that could be expected in the environment. The soil matrix is apparently trapping and filtering NMs. Further studies should focus more on indirect effects in biological communities rather than only on effects at the individual level. Aquatic biota, mainly from freshwater ecosystems, seemed to be at higher risk, since dose effect concentrations recorded were remarkable lower, at least for some NMs. The toxic effects recorded on different culture lines, also give rise to serious concerns regarding the potential effects on human health. However, few data exists about environmental concentrations to support the calculation of risks to ecosystems and humans.