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ENRHES – Engineered nanoparticles: review of health and environmental safety

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... Most studies evaluated specific MNMs. There were seven that evaluated TiO 2 ( Kuempel et al., 2006, Aschberger et al., 2011, National Institute for Occupational Safety and Health, 2011, Ogura et al., 2011, Warheit, 2013, Stockmann-Juvala et al., 2014, ŚwidwińskaGajewska and Czerczak, 2014), six that evaluated carbon nanotubes ( Luizi, 2009, Stone, 2009, Pauluhn, 2010, Aschberger et al., 2011, National Institute for Occupational Safety and Health, 2013, Nakanishi et al., 2015), three evaluated fullerene ( Stone, 2009, Aschberger et al., 2010, Shinohara et al., 2011), three evaluated nanosilver ( Stone, 2009, Aschberger et al., 2011, Swidwinska-Gajewska and Czerczak, 2015), and one study evaluated amorphous SiO2, low-toxicity dust, nanocellulose and nanoclays ( Stockmann-Juvala et al., 2014). ...
... Most studies evaluated specific MNMs. There were seven that evaluated TiO 2 ( Kuempel et al., 2006, Aschberger et al., 2011, National Institute for Occupational Safety and Health, 2011, Ogura et al., 2011, Warheit, 2013, Stockmann-Juvala et al., 2014, ŚwidwińskaGajewska and Czerczak, 2014), six that evaluated carbon nanotubes ( Luizi, 2009, Stone, 2009, Pauluhn, 2010, Aschberger et al., 2011, National Institute for Occupational Safety and Health, 2013, Nakanishi et al., 2015), three evaluated fullerene ( Stone, 2009, Aschberger et al., 2010, Shinohara et al., 2011), three evaluated nanosilver ( Stone, 2009, Aschberger et al., 2011, Swidwinska-Gajewska and Czerczak, 2015), and one study evaluated amorphous SiO2, low-toxicity dust, nanocellulose and nanoclays ( Stockmann-Juvala et al., 2014). ...
... Most studies evaluated specific MNMs. There were seven that evaluated TiO 2 ( Kuempel et al., 2006, Aschberger et al., 2011, National Institute for Occupational Safety and Health, 2011, Ogura et al., 2011, Warheit, 2013, Stockmann-Juvala et al., 2014, ŚwidwińskaGajewska and Czerczak, 2014), six that evaluated carbon nanotubes ( Luizi, 2009, Stone, 2009, Pauluhn, 2010, Aschberger et al., 2011, National Institute for Occupational Safety and Health, 2013, Nakanishi et al., 2015), three evaluated fullerene ( Stone, 2009, Aschberger et al., 2010, Shinohara et al., 2011), three evaluated nanosilver ( Stone, 2009, Aschberger et al., 2011, Swidwinska-Gajewska and Czerczak, 2015), and one study evaluated amorphous SiO2, low-toxicity dust, nanocellulose and nanoclays ( Stockmann-Juvala et al., 2014). ...
Article
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Background: The toxicological properties of manufactured nanomaterials (MNMs) can be different from their bulk-material and uncertainty remains about the adverse health effects they may have on humans. Proposals for OELs have been put forward which can be useful for risk management and workers’ protection. We performed a systematic review of proposals for OELs for MNMs to better understand the extent of such proposals, as well as their derivation methods. Methods: We searched PubMed and Embase with an extensive search string and also assessed the references in the included studies. Two authors extracted data independently. Results: We identified 20 studies that proposed in total 56 OEL values. Of these, two proposed a generic level for all MNMs, 14 proposed a generic OEL for a category of MNMs and 40 proposed an OEL for a specific nanomaterial. For specific fibres, four studies proposed a similar value but for carbon nanotubes (CNTs) the values differed with a factor ranging from 30 to 50 and for metals with a factor from 100 to 300. The studies did not provide explanations for this variation. We found that exposure to MNMs measured at selected workplaces may exceed even the highest proposed OEL. This indicates that the application and use of OELs may be useful for exposure reduction. Conclusion: OELs can provide a valuable reference point for exposure reduction measures in workplaces. There is a need for more and better supported OELs based on a more systematic approach to OEL derivation.
... The huge diversity of ENPs, in terms of chemical identity, particle size, and surface functionalization, makes it a difficult task to identify the inherent particle properties that determine the ecotoxicity of ENPs. [21,22] The lack of common descriptors, as well as the fundamental difference between ENPs and soluble compounds, raises serious concerns about the suitability of current guideline tests when applied to ENPs, and hence the The number of products on the market containing engineered nanoparticles (ENPs) has increased significantly, and concerns have been raised regarding their ecotoxicological effects. Environmental safety assessments as well as relevant and reliable ecotoxicological data are required for the safe and sustainable use of ENPs. ...
... However, these methods have all been found to influence the ecotoxicity of ENPs and could, therefore, hamper interpretation of the results obtained. [22] Dissolution becomes relevant for ENP ecotoxicity when ions or molecules are released from the ENP surface to the media. ENPs may be soluble to varying extents-from insoluble to poorly soluble, partly soluble, or completely soluble-depending on the ENP as well as on the testing conditions (e.g. the test medium), as illustrated in Figure 2. Understanding dissolution is fundamental to the interpretation of the ecotoxicity effects of ENPs. ...
... Stone et al. [22] stated in a comprehensive review that "only few studies have dealt with bioaccumulation of metal ENPs". In 2013, Hou et al. [91] reviewed 65 papers on the biological accumulation of ENPs in water, soil, or sediment. ...
Article
Full-text available
Over the last decade the number of products on the market containing engineered nanoparticles (ENPs) has increased significantly and concerns have been raised regarding the potential for ecotoxicological effects of ENPs. To promote safe and sustainable use of ENPs, environmental safety assessments are needed and for this purpose relevant and reliable ecotoxicological data is demanded. While the literature on ecotoxicological effects and uptake of ENPs is rapidly expanding, the applicability of reported data of ENPs for hazard assessment purposes is questionable. A major knowledge gap is whether nanoparticle effects occur when test organisms are exposed to ENPs in aquatic test systems. This knowledge gap is not straightforward to fill, due to the high variability in ENP types, and the different behavior of ENPs compared to "ordinary" (dissolved) chemicals in the ecotoxicity test systems. The risk of generating false negative, as well as false positive, results in the currently used tests is high, but in most cases difficult to assess. This literature review outlines some of the pitfalls in aquatic toxicity testing of ENPs which may lead to misinterpretation of test results. Furthermore, the review proposes response types to account for in order to reveal potential nanoparticle effects in the aquatic test organisms used for risk assessments of ENPs.
... The huge diversity of ENPs, in terms of chemical identity, particle size, and surface functionalization, makes it a difficult task to identify the inherent particle properties that determine the ecotoxicity of ENPs. [21,22] The lack of common descriptors, as well as the fundamental difference between ENPs and soluble compounds, raises serious concerns about the suitability of current guideline tests when applied to ENPs, and hence the The number of products on the market containing engineered nanoparticles (ENPs) has increased significantly, and concerns have been raised regarding their ecotoxicological effects. Environmental safety assessments as well as relevant and reliable ecotoxicological data are required for the safe and sustainable use of ENPs. ...
... However, these methods have all been found to influence the ecotoxicity of ENPs and could, therefore, hamper interpretation of the results obtained. [22] Dissolution becomes relevant for ENP ecotoxicity when ions or molecules are released from the ENP surface to the media. ENPs may be soluble to varying extents-from insoluble to poorly soluble, partly soluble, or completely soluble-depending on the ENP as well as on the testing conditions (e.g. the test medium), as illustrated in Figure 2. Understanding dissolution is fundamental to the interpretation of the ecotoxicity effects of ENPs. ...
... Stone et al. [22] stated in a comprehensive review that "only few studies have dealt with bioaccumulation of metal ENPs". In 2013, Hou et al. [91] reviewed 65 papers on the biological accumulation of ENPs in water, soil, or sediment. ...
Article
Full-text available
Over the last decade the number of products on the market containing engineered nanoparticles (ENPs) has increased significantly and concerns have been raised regarding the potential for ecotoxicological effects of ENPs. To promote safe and sustainable use of ENPs, environmental safety assessments are needed and for this purpose relevant and reliable ecotoxicological data is demanded. While the literature on ecotoxicological effects and uptake of ENPs is rapidly expanding, the applicability of reported data of ENPs for hazard assessment purposes is questionable. A major knowledge gap is whether nanoparticle effects occur when test organisms are exposed to ENPs in aquatic test systems. This knowledge gap is not straightforward to fill, due to the high variability in ENP types, and the different behavior of ENPs compared to "ordinary" (dissolved) chemicals in the ecotoxicity test systems. The risk of generating false negative, as well as false positive, results in the currently used tests is high, but in most cases difficult to assess. This literature review outlines some of the pitfalls in aquatic toxicity testing of ENPs which may lead to misinterpretation of test results. Furthermore, the review proposes response types to account for in order to reveal potential nanoparticle effects in the aquatic test organisms used for risk assessments of ENPs.
... Bayer (Pauluhn, 2010), Nanocyl (Luizi, 2009) andNIOSH (National Institute for Occupational Safety andHealth, 2013) proposed OELs for multiwall carbon nanotubes (MWCNTs). DNELs were calculated in an experimental study by Stone et al. applying the DNEL methodology with the prescribed assessment factors to MWCNTs, fullerenes, silver (Ag) and titanium dioxide (TiO 2 ) (Stone, 2009). ...
... Studies with a categorical approach. We found six studies that used a categorical approach when they derived an OEL for a group of nanomaterials ( Warheit, 2013), six that evaluated carbon nanotubes (Aschberger et al., 2011;Luizi, 2009;Nakanishi et al., 2015; National Institute for Occupational Safety and Health, 2013; Pauluhn, 2010;Stone, 2009), three evaluated fullerene (Aschberger et al., 2010;Shinohara et al., 2011;Stone, 2009), three evaluated nanosilver (Aschberger et al., 2011;Stone, 2009;Swidwinska-Gajewska & Czerczak, 2015), and one study evaluated amorphous SiO 2 , low-toxicity dust, nanocellulose and nanoclays (Stockmann-Juvala et al., 2014). ...
... Studies with a categorical approach. We found six studies that used a categorical approach when they derived an OEL for a group of nanomaterials ( Warheit, 2013), six that evaluated carbon nanotubes (Aschberger et al., 2011;Luizi, 2009;Nakanishi et al., 2015; National Institute for Occupational Safety and Health, 2013; Pauluhn, 2010;Stone, 2009), three evaluated fullerene (Aschberger et al., 2010;Shinohara et al., 2011;Stone, 2009), three evaluated nanosilver (Aschberger et al., 2011;Stone, 2009;Swidwinska-Gajewska & Czerczak, 2015), and one study evaluated amorphous SiO 2 , low-toxicity dust, nanocellulose and nanoclays (Stockmann-Juvala et al., 2014). ...
Article
Full-text available
Background Engineered nanomaterials (ENMs) have a large economic impact in a range of fields, but the concerns about health and safety of occupational activities involving nanomaterials have not yet been addressed. Monitoring exposure is an important step in risk management. Hence, the interest for reviewing studies that reported a potential for occupational exposure. Methods We systematically searched for studies published between January 2000 and January 2015. We included studies that used a comprehensive method of exposure assessment. Studies were grouped by nanomaterial and categorized as carbonaceous, metallic, or nanoclays. We summarized data on task, monitoring strategy, exposure outcomes, and controls in a narrative way. For each study, the strength of the exposure assessment was evaluated using predetermined criteria. Then, we identified all exposure situations that reported potential occupational exposure based on qualitative or quantitative outcomes. Results were synthesized and general conclusion statements on exposure situations were formulated. The quality of evidence for the conclusion statements was rated as low, moderate, or high depending on the number of confirmed exposure situations, the strength of the exposure assessment, and the consistency of the results. Results From the 6403 references initially identified, 220 were selected for full-text screening. From these, 50 studies describing 306 exposure situations in 72 workplaces were eligible for inclusion (27 industrial-scale plants and 45 research or pilot-scale units). There was a potential for exposure to ENMs in 233 of the exposure situations. Exposure occurred in 83% (N = 107) of the situations with carbonaceous ENMs, in 73% (N = 120) of those with metallic ENMs and in 100% (N = 6) of those with nanoclay. Concentrations of elemental carbon in the workers’ breathing zone ranged from not detected (ND) to 910 µg m−3 with local engineering controls (LEC), and from ND to 1000 µg m−3 without those controls. For carbon nanofibres (CNFs), particle counts ranged from ND to 1.61 CNF structures cm−3 with LEC, and from 0.09 to 193 CNF structures cm−3 without those controls. The mass concentrations of aluminium oxide, titanium dioxide, silver, and iron nanoparticles (NPs) were ND, 10–150, 0.24–0.43, and 32 µg m−3 with LEC, while they were <0.35, non-applicable, 0.09–33, and 335 µg m−3 without those controls, respectively. Conclusions Regarding the potential of exposure in the workplace, we found high-quality evidence for multiwalled carbon nanotubes (CNTs), single-walled CNTs, CNFs, aluminium oxide, titanium dioxide, and silver NPs; moderate-quality evidence for non-classified CNTs, nanoclays, and iron and silicon dioxide NPs; low-quality evidence for fullerene C60, double-walled CNTs, and zinc oxide NPs; and no evidence for cerium oxide NPs. We found high-quality evidence that potential exposure is most frequently due to handling tasks, that workers are mostly exposed to micro-sized agglomerated NPs, and that engineering controls considerably reduce workers’ exposure. There was moderate-quality evidence that workers are exposed in secondary manufacturing industrial-scale plants. There was low-quality evidence that workers are exposed to airborne particles with a size <100nm. There were no studies conducted in low- and middle-income countries.
... Wartości DNEL dla fulerenu zaproponował zespół ekspertów pod kierunkiem prof. Vicki Stone w ramach projektu ENRHES (Engineered nanoparticles: Review health and environmental safety -Nanocząstki projektowane: przegląd dotyczący bezpieczeństwa i zdrowia środowiskowego) [39]. Na podstawie eksperymentów prowadzonych drogą inhalacyjną i pokarmową Stone i wsp. ...
... Na podstawie eksperymentów prowadzonych drogą inhalacyjną i pokarmową Stone i wsp. ustalili krytyczny efekt działania fulerenu jako pojawienie się stanu zapalnego i odpowiedź oksydacyjna o działaniu progowym [39]. Nie ma wystarczających opublikowanych danych na temat bezprogowego działania genotoksycznego fulerenu. ...
... Nie ma wystarczających opublikowanych danych na temat bezprogowego działania genotoksycznego fulerenu. Sugeruje się nawet, że podawany w niskich dawkach może mieć działanie antyoksydacyjne i przeciwzapalne [39]. ...
Article
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Fullerenes are molecules composed of an even number of carbon atoms of a spherical or an ellipsoidal, closed spatial structure. The most common fullerene is the C60 molecule with a spherical structure - a truncated icosahedron, compared to a football. Fullerenes are widely used in the diagnostics and medicine, but also in the electronics and energy industry. Occupational exposure to fullerene may occur during its production. The occupational concentrations of fullerenes reached 0.12-1.2 μ/m3 for nanoparticles fraction (< 100 nm), which may evidence low exposure levels. However, fullerene mostly agglomerates into larger particles. Absorption of fullerene by oral and respiratory routes is low, and it is not absorbed by skin. After intravenous administration, fullerene accumulates mainly in the liver but also in the spleen and the kidneys. In animal experiments there was no irritation or skin sensitization caused by fullerene, and only mild irritation to the eyes. Fullerene induced transient inflammation in the lungs in inhalation studies in rodents. Oral exposure does not lead to major adverse effects. Fullerene was not mutagenic, genotoxic or carcinogenic in experimental research. However, fullerene may cause harmful effects on the mice fetus when administered intraperitoneally or intravenously. Pristine C60 fullerene is characterized by poor absorption and low toxicity, and it does not pose a risk in the occupational environment. The authors of this study are of the opinion that there is no ground for estimating the maximum allowable concentration (NDS) of pristine fullerene C60. Fullerene derivatives, due to different characteristics, require separate analysis in terms of occupational risk assessment. Med Pr 2016;67(3):397-410. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.
... Wartości DNEL wraz z podstawami do ich oszacowania dla nanosrebra zaproponował zespół ekspertów pod kierunkiem prof. Vicki Stone w ramach projektu ENRHES (Engineered Nanoparticles: Review Health and Environmental Safety – Nanocząstki projektowane: przegląd dotyczący bezpieczeństwa i zdrowia środowiskowego) [53]. Podstawą szacowania poziomu DNEL zaproponowanego przez ekspertów ENRHES [53] jest 90-dniowe badanie przeprowadzone na szczurach narażanych inhalacyjnie (całe ciało) na cząstki srebra o średnicy 18– –19 nm i stężeniu 0,6–3×10 6 cząstek/cm 3 (49–515 μg/m 3 ) przez 6 godz. ...
... Vicki Stone w ramach projektu ENRHES (Engineered Nanoparticles: Review Health and Environmental Safety – Nanocząstki projektowane: przegląd dotyczący bezpieczeństwa i zdrowia środowiskowego) [53]. Podstawą szacowania poziomu DNEL zaproponowanego przez ekspertów ENRHES [53] jest 90-dniowe badanie przeprowadzone na szczurach narażanych inhalacyjnie (całe ciało) na cząstki srebra o średnicy 18– –19 nm i stężeniu 0,6–3×10 6 cząstek/cm 3 (49–515 μg/m 3 ) przez 6 godz. dziennie, 5 dni w tygodniu [54] . ...
... Ta obserwacja skłania do traktowania nanosrebra z dużą ostrożnością i podejmowania środków kontroli ryzyka podobnie jak w przypadku rozpuszczalnych związków srebra, w których kluczową rolę odgrywa działanie formy jonowej srebra. Grupa naukowców pod kierunkiem Stone [53] opracowała poziomy DNEL dla poszczególnych nanoobiektów , w tym również nanosrebra. Z uwagi na wysokie współczynniki modyfikacyjne stosowane przy szacowaniu wartości DNEL wyniki uzyskane dla poszczególnych substancji chemicznych są często dużo niższe w porównaniu z obowiązującymi wartościami NDS. ...
Article
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Historically, nanosilver has been known as colloidal silver composed of particles with a size below 100 nm. Silver nanoparticles are used in many technologies, creating a wide range of products. Due to antibacterial properties nanosilver is used, among others, in medical devices (wound dressings), textiles (sport clothes, socks), plastics and building materials (paints). Colloidal silver is considered by many as an ideal agent in the fight against pathogenic microorganisms, unlike antibiotics, without side effects. However, in light of toxicological research, nanosilver is not inert to the body. The inhalation of silver nanoparticles have an adverse effect mainly on the liver and lung of rats. The oxidative stress caused by reactive oxygen species is responsible for the toxicity of nanoparticles, contributing to cytotoxic and genotoxic effects. The activity of the readily oxidized nanosilver surface underlies the molecular mechanism of toxicity. This leads to the release of silver ions, a known harmful agent. Occupational exposure to silver nanoparticles may occur in the process of its manufacture, formulation and also usage during spraying, in particular. In Poland, as well as in other countries of the world, there is no separate hygiene standards applicable to nanomaterials. The present study attempts to estimate the value of MAC-TWA (maximum admissible concentration - the time-weighted average) for silver - a nano-objects fraction, which amounted to 0.01 mg/m3;. The authors are of the opinion that the current value of the MAC-TWA for silver metallic - inhalable fraction (0.05 mg/m3;) does not provide sufficient protection against the harmful effects of silver in the form of nano-objects. Med Pr 2015;66(3):429-442. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.
... Manufactured nanomaterials are used in a rapidly increasing number of products available to industries and private consumers and the diversity of commercialized nanomaterials and products is immense. More and more evidence has emerged in the scientific literature that some nanomaterials might have hazardous properties (for a comprehensive review, seeStone et al. 2010;Mikkelsen et al. 2011; SCHER, SCENIHR, and SCCS 2013). However, it is a great challenge to clearly extract and communicate the essence of exposure and hazard information efficiently. ...
... For inhalation of dusts and mists (solid particles and liquid droplets) the acute toxicity estimate cut-off has been set to 5 mg/l. 5. Is there indications that the nanomaterial causes genotoxic, mutagenic, carcinogenic, respiratory, cardiovascular, neurotoxic, or reproductive effects in humans and/or laboratory animals or has organspecific accumulation been documented? As shown inStone et al. (2010), Hougaard et al. (2010), Halappanavar et al. (2011, and Hansen et al. (2013a), there is compelling evidence that exposure to some nanomaterials may be associated with effects in one or more of these end-points. Due to their severity, a response significantly over background in any of these endpoints results in a ''red'' classification. ...
... Hence the color-code that best reflects the human hazard profile of carbon nanotubes is red based evidence of HARN. The shape of the nanosilver particles used in NANOVER TM Cleansing Soap are not reported, but nanosilver is normally commercialized as powder, flakes, grains, etc. (Mikkelsen et al. 2011), which do not fulfill the HARN requirements of having a diameter aspect ratio greater than 10 to 1. Bulk silver furthermore has not been classified according to CLP and either has nanosilver specifically been reported to be acute toxic (Stone et al. 2010;Mikkelsen et al. 2011). The key question in regard to the human health hazard evaluation of nanosilver is whether it fulfils question 5, i.e., are there indications that the nanomaterial causes genotoxic, mutagenic, carcinogenic, respiratory, cardiovascular, neurotoxic, or reproductive effects in humans and/or laboratory animals or has organ-specific accumulation been documented? ...
Article
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The literature on nano(eco)toxicology is growing rapidly and has become increasingly difficult to interpret. We have developed a systematic tool called NanoRiskCat that can support companies and regulators in their first-tier assessment and communication on what they know about the hazard and exposure potential of consumer products containing engineered nanomaterials. The final outcome of NanoRiskCat is communicated in the form of a short-title describing the intended use and five colored dots. The first three dots refer to the qualitative exposure potential for professional end-users, consumers and the environment, whereas the last two refers to the hazard potential for humans and the environment. Each dot can be assigned one of four different colors, i.e. red, yellow, green, and gray indicating high, medium, low, and unknown, respectively. In this paper, we first introduce the criteria used to evaluate the exposure potential and the human and environmental hazards of specific uses of the nanoproduct. We then apply NanoRiskCat to eight different nanoproducts. The human and environmental exposure potential was found to be high (i.e., red) for many of the products due to direct application on skin and subsequent environmental release. In the NanoRiskCat evaluation, many of the nanomaterials achieve a red human and environmental hazard profile as there is compelling in vivo evidence to associate them with irreversible effects, e.g., carcinogenicity, respiratory, and cardiovascular effects, etc., in laboratory animals. A significant strength of NanoRiskCat is that it can be used even in cases where lack of data is prominent.
... 5 Nanotechnology is a sector of high-tech industry that has already created a multibillion $US market, and is widely expected to grow to 1 trillion (10 18 ) US dollars by 2015. 6 Nanotechnology research and development can integrate the nanoscale structures into larger material components, systems, and architectures. 7 The majority of the NPs currently in use today have been made from transition metals, silicon, different forms of carbon (carbon nanotubes; fullerenes), and metal oxides (such as zinc dioxide and titanium dioxide). ...
... As stated before, the possible health effects arising from exposure to NPs may be better correlated with surface area, rather than with mass concentration. 6,16 NPs have some essential properties that could be directly related to their pathogenicity: -As particles less than 100 nm, they may have more toxicity than larger sized particles. -Generally they are considered as fibre shaped, and so might behave like some other pathogenic fibres (asbestos, man-made fibres). ...
... 27 At present, carrying out risk assessment of NPs can only be done sensibly on a case-by-case basis. 6 Most of the studies about the effects of respiratory exposure to NPs involve pulmonary models and are performed through instillation, aspiration and inhalation of carbon nanotubes (the most studied NPs) in rodent species. Table 1 summarizes some of the main in vivo investigations regarding the respiratory effects of carbon nanotubes. ...
Article
Full-text available
The recently emergent field of Nanotechnology involves the production and use of structures at the nanoscale. Research at atomic, molecular or macromolecular levels, has led to new materials, systems and structures on a scale consisting of particles less than 100nm and showing unique and unusual physical, chemical and biological properties, which has enabled new applications in diverse fields, creating a multimillion-dollar high-tech industry. Nanotechnologies have a wide variety of uses from nanomedicine, consumer goods, electronics, communications and computing to environmental applications, efficient energy sources, agriculture, water purification, textiles, and aerospace industry, among many others. The different characteristics of nanoparticles such as size, shape, surface charge, chemical properties, solubility and degree of agglomeration will determine their effects on biological systems and human health, and the likelihood of respiratory hazards. There are a number of new studies about the potential occupational and environmental effects of nanoparticles and general precautionary measures are now fully justified. Adverse respiratory effects include multifocal granulomas, peribronchial inflammation, progressive interstitial fibrosis, chronic inflammatory responses, collagen deposition and oxidative stress. The authors present an overview of the most important studies about respiratory nanotoxicology and the effects of nanoparticles and engineered nanomaterials on the respiratory system.
... Risk analysis evaluates the likelihood of adverse health or environmental effects due to exposure to stressors and has been used for chemical regulation by many government agencies and international organizations such as the US Environmental Protection Agency (US EPA), the European Chemical Agency (ECHA), the Organization for Economic cooperation and Development (OECD) and the World Health Organization (WHO). However, its feasibility for ENMs has identified substantial limitations (Linkov et al. 2009; Hansen 2009; Hristozov & Malsch 2009; Stone et al. 2009). Gaps in basic information on hazard, exposure and dose–response leads to ambiguous, largely qualitative risk estimations based on expert judgements, which may fail to support proper risk management actions (Hristozov et al. 2012). ...
... The production of nano- TiO 2 in the US is expected to grow from about 30,000 million tons in 2012 to the estimated 2,400,000 million tons in 2026 and it will account for about 99% of the total US TiO 2 production (Robichaud et al. 2010). Although TiO 2 is generally considered a biologically inert material, nano-TiO 2 may pose adverse health effects due to its enhanced reactivity (Stone et al. 2009). Therefore, it is essential to ensure that this material is safe for workers and consumers. ...
... For this reason " in vivo " data are generally considered much more adequate in human health hazard and risk analyses than " in vitro " results. Inhalation is considered the primary entry route of airsuspended particles in the human organism (Stone et al. 2009). Highest airborne concentrations of nano-TiO 2 are expected in occupational settings (Brouwer et al. 2011; Mueller & Nowack 2008; Stone et al. 2009). ...
Article
Abstract Hazard identification is an important step in assessing nanomaterial risk and is required under multiple regulatory frameworks in the US, Europe and worldwide. Given the emerging nature of the field and complexity of nanomaterials, multiple studies on even basic material properties often result in varying data pointing in different directions when data interpretation is attempted. Weight of Evidence (WOE) evaluation has been recommended for nanomaterial risk assessment, but the majority of WOE frameworks are qualitative in nature and do not satisfy the growing needs for objectivity and transparency that are necessary for regulatory decision making. This paper implements a quantitative WOE framework that utilizes Multi-Criteria Decision Analysis methodology for integrating individual studies on nanomaterial hazard resulting from physico-chemical and toxicological properties of nanomaterials. For the first time, a WOE approach explicitly integrates expert evaluation of data quality of available information. Application of the framework is illustrated for titanium dioxide nanoparticles (nano-TiO2), but the approach is designed to compare the relative hazard of several nanomaterials as well as emerging stressors in general.
... The worst-case conditions identified in this analysis are those which are critical to include in worst-case estimates within subsequent environmental risk assessments of these applications. We focus primarily on the potential environmental risks of these two nanoparticles in select applications since there has been relatively little research thus far dedicated to the field of environmental risk assessment of nanomaterials (Baun et al., 2008a) despite the anticipated increased levels of environmental exposures through direct or indirect exposure routes (Boxall et al., 2007; Wijnhoven et al., 2009; Stone et al., 2010). Results generated from this analysis may ultimately help prioritize research areas for environmental risk assessments of nZVI and C 60 in these applications as well as demonstrate the use of worst-case conditions to potentially optimize future research efforts for other nanomaterials. ...
... Developing worst-case conditions for these case studies is based on the application of the Worst-Case Definition (WCD) model developed by Sørensen et al. (2009a), which is briefly outlined in the subsequent Section (2.2). We focus specifically on environmental risk assessment of these two nanoparticles (nZVI, C 60 ), both of which are expected to enter the environment at increasing rates through various applications in coming years (Karn et al., 2009; Stone et al., 2010). nZVI was chosen as one case study since it is directly injected into soil and groundwater through in situ remediation techniques (Tratnyek and Johnson, 2006), and hence there are definite environmental exposures through its normal, intended use patterns. ...
... The second case study focuses on C 60 as an additive in an engine oil lubricant (Franco et al., 2007; Bardahl, 2010) in which C 60 is suspended in a liquid (oil) and use by professionals and consumers may potentially result in unintended environmental exposures through normal use patterns (Hansen et al., 2008). C 60 was also chosen given its use in a wide range of applications, estimated production volumes (i.e. up to 80 tons per year, Hendren et al., 2011), and it is one of the most frequently studied nanoparticles in nano-risk research (Stone et al., 2010). In addition to the intended use of nZVI and C 60 in these applications, this analysis also includes the possibility of spills and leaks during use of these applications, whereby e.g. ...
Article
Conducting environmental risk assessment of engineered nanomaterials has been an extremely challenging endeavor thus far. Moreover, recent findings from the nano-risk scientific community indicate that it is unlikely that many of these challenges will be easily resolved in the near future, especially given the vast variety and complexity of nanomaterials and their applications. As an approach to help optimize environmental risk assessments of nanomaterials, we apply the Worst-Case Definition (WCD) model to identify best estimates for worst-case conditions of environmental risks of two case studies which use engineered nanoparticles, namely nZVI in soil and groundwater remediation and C(60) in an engine oil lubricant. Results generated from this analysis may ultimately help prioritize research areas for environmental risk assessments of nZVI and C(60) in these applications as well as demonstrate the use of worst-case conditions to optimize future research efforts for other nanomaterials. Through the application of the WCD model, we find that the most probable worst-case conditions for both case studies include i) active uptake mechanisms, ii) accumulation in organisms, iii) ecotoxicological response mechanisms such as reactive oxygen species (ROS) production and cell membrane damage or disruption, iv) surface properties of nZVI and C(60), and v) acute exposure tolerance of organisms. Additional estimates of worst-case conditions for C(60) also include the physical location of C(60) in the environment from surface run-off, cellular exposure routes for heterotrophic organisms, and the presence of light to amplify adverse effects. Based on results of this analysis, we recommend the prioritization of research for the selected applications within the following areas: organism active uptake ability of nZVI and C(60) and ecotoxicological response end-points and response mechanisms including ROS production and cell membrane damage, full nanomaterial characterization taking into account detailed information on nanomaterial surface properties, and investigations of dose-response relationships for a variety of organisms.
... 4 The environmental effects of the AgNPs discharged into aquatic environments are largely unknown. 1,5 However, laboratory ecotoxicological studies on fishes, crustaceans, algae and bacteria have shown toxic effects on test organisms exposed to AgNPs. 1,[5][6][7] Due to the antimicrobial properties of AgNPs, it is important to understand which factors control their toxicity toward environmental microorganisms since they play important roles in major biogeochemical cycles, in the production of natural organic matter and in the recycling of nutrients. ...
... 1,5 However, laboratory ecotoxicological studies on fishes, crustaceans, algae and bacteria have shown toxic effects on test organisms exposed to AgNPs. 1,[5][6][7] Due to the antimicrobial properties of AgNPs, it is important to understand which factors control their toxicity toward environmental microorganisms since they play important roles in major biogeochemical cycles, in the production of natural organic matter and in the recycling of nutrients. Bacterial sensitivity to silver nanoparticles and ionic silver have been demonstrated on reference bacterial strains of the genera Bacillus, Escherichia, Pseudomonas and Vibrio 7-10 as well as on bacterial communities. ...
... 4 The environmental effects of the AgNPs discharged into aquatic environments are largely unknown. 1,5 However, laboratory ecotoxicological studies on fishes, crustaceans, algae and bacteria have shown toxic effects on test organisms exposed to AgNPs. 1,[5][6][7] Due to the antimicrobial properties of AgNPs, it is important to understand which factors control their toxicity toward environmental microorganisms since they play important roles in major biogeochemical cycles, in the production of natural organic matter and in the recycling of nutrients. ...
... 1,5 However, laboratory ecotoxicological studies on fishes, crustaceans, algae and bacteria have shown toxic effects on test organisms exposed to AgNPs. 1,[5][6][7] Due to the antimicrobial properties of AgNPs, it is important to understand which factors control their toxicity toward environmental microorganisms since they play important roles in major biogeochemical cycles, in the production of natural organic matter and in the recycling of nutrients. Bacterial sensitivity to silver nanoparticles and ionic silver have been demonstrated on reference bacterial strains of the genera Bacillus, Escherichia, Pseudomonas and Vibrio 7-10 as well as on bacterial communities. ...
Article
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The aim of this study was to evaluate the stability of AgNPs suspensions in different exposure solutions characteristic of natural waters or culture medium used in microbial ecotoxicology studies. The behavior of AgNPs in solution depends on the physicochemical characteristics of the receptor media. In nanopure water, the size of AgNPs was stable over time. When the ionic strength of the solution was enhanced, by adding NaCl, CaCl2 or MgCl2 at 25 PSU, the size of AgNPs increased rapidly and corresponded to an aggregation of the nanoparticles. This aggregation was modulated by the valence of the cations. The divalent cations were favored a faster aggregation than monovalent cations. The presence of a complex mixture of anions as in artificial seawater or as in the F/2 medium (Cl-, HCO3-, SO42-) decreased the aggregation rate by interacting with AgNP surfaces. At high ionic strength, the presence of organic matter such as tryptone and yeast extract in culture media (Luria Broth, LB) decreased the aggregation rate of AgNPs. The lower aggregation rate, caused by the sorption of organic matter, was temporary and did not exceed a few hours. This study shows the importance to control the aging of colloidal AgNPs suspensions for nanotoxicity assays
... Most of these reviews commonly conclude that more research is needed in the field of nano-ecotoxicology and future studies have to include better particle and exposure characterization. Furthermore, it is often concluded that for the time being a risk assessment of nanomaterials can only be sensibly carried out on a case-by-case basis [16]. For CNT, a few scientific studies relevant for risk assessment have been published in recent years. ...
... Environmental risk assessment of nanomaterials requires thorough characterization of nanoparticles subjected to risk evaluations and suitable methods are needed for determining the realistic environmental concentrations in complex matrices [7]. The first ecotoxicological studies were published almost ten years ago, but to date there is still a limited number of high quality data available for hazard assessment of nanomaterials [10,16,148]. It has currently been impossible to group nanomaterials on the basis of inherent properties, since mechanisms of toxicity are not yet well defined or understood. ...
Article
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Carbon nanotubes (CNT) have numerous industrial applications and may be released to the environment. In the aquatic environment, pristine or functionalized CNT have different dispersion behavior, potentially leading to different risks of exposure along the water column. Data included in this review indicate that CNT do not cross biological barriers readily. When internalized, only a minimal fraction of CNT translocate into organism body compartments. The reported CNT toxicity depends on exposure conditions, model organism, CNT-type, dispersion state and concentration. In the ecotoxicological tests, the aquatic organisms were generally found to be more sensitive than terrestrial organisms. Invertebrates were more sensitive than vertebrates. Single-walled CNT were found to be more toxic than double-/multi-walled CNT. Generally, the effect concentrations documented in literature were above current modeled average environmental concentrations. Measurement data are needed for estimation of environmental no-effect concentrations. Future studies with benchmark materials are needed to generate comparable results. Studies have to include better characterization of the starting materials, of the dispersions and of the biological fate, to obtain better knowledge of the exposure/effect relationships.
... Furthermore, among the nanoparticle properties, it is hard to find out the specific feature responsible of the nanomaterial ecotoxicity. As nanoparticles are, at the same time, physical objects, possible sources of inorganic ions (due to degradation phenomena), and chemicals (due to their surface chemistry), the attribution of the main origin of hazard is tricky 18,19 . First of all, ecotoxicity effects may be ruled by the physical form of nanomaterials and/or the presence of dissolved species 20,21 , which may contribute to toxicity through different modes of action. ...
Article
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Nano-ecotoxicology is extensively debated and nanomaterial surface reactivity is an emerging topic. Iron oxide nanoparticles are widely applied, with organic or inorganic coatings for stabilizing their suspensions. Surface active maghemite nanoparticles (SAMNs) are the unique example of naked iron oxide displaying high colloidal and structural stability in water and chemical reactivity. The colloidal behavior of SAMNs was studied as a function of the medium salinity and protocols of acute and chronic toxicity on Daphnia magna were consequently adapted. SAMN distribution into the crustacean, intake/depletion rates and swimming performances were evaluated. No sign of toxicity was detected in two model organisms from the first trophic level (P. subcapitata and L. minor). In D. magna, acute EC50 values of SAMN was assessed, while no sub-lethal effects were observed and the accumulation of SAMNs in the gut appeared as the sole cause of mortality. Fast depuration and absence of delayed effects indicated no retention of SAMNs within the organism. In spite of negligible toxicity on D. magna adults, SAMN surface reactivity was responsible of membrane bursting and lethality on embryos. The present study offers a contribution to the nascent knowledge concerning the impact of nanoparticle surface reactivity on biological interfaces.
... LCA is particularly useful in stage-gate product development approaches, where such studies can be built very early on in product development (that is, early-stage development) to provide hot-spot analysis and guidance for sustainable production and consumption. However, in the context of nanotechnologies, any potential toxicological hazards [6][7][8][9][10] resulting from emissions of ENM currently remain undetected due to data 11 and methodological 12 gaps in LCA. ...
Article
It has been some 15 years since the topics of sustainability and nanotechnologies first appeared together in the scientific literature and became a focus of organizations' research and policy developments. On the one hand, this focus is directed towards approaches and tools for risk assessment and management and on the other hand towards life-cycle thinking and assessment. Comparable to their application for regular chemicals, each tool is seen to serve separate objectives as it relates to evaluating nanotechnologies' safety or resource efficiency, respectively. While nanomaterials may provide resource efficient production and consumption, this must balance any potential hazards they pose across their life-cycles. This Perspective advocates for integrating these two tools at the methodological level for achieving this objective, and it explains what advantages and challenges this offers decision-makers while highlighting what research is needed to further enhance integration.
... Engineered nanomaterials (ENM) provide benefits across many sectors, 1 but they also raise concerns regarding poten-tial environmental and human health hazards. [2][3][4] While nanotechnologies can be evaluated with life cycle assessment (LCA) to determine their potential resource efficiencies and environmental and human health impacts, LCA does not evaluate the direct environmental and human health hazards posed by ENM emissions across their life cycles. 5,6 While it is possible to build life cycle inventories (LCI) that estimate and quantify ENM emissions, 7-10 currently available life cycle impact assessment (LCIA) methodologies do not cover nanospecific characterization factors (CF) that are necessary for quantifying the fate of, exposure to, and impacts from those emissions in an LCA. ...
Article
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Life cycle assessment is used during the developmental stages of products and technologies. In the case of emerging technologies such as engineered nanomaterials there are limitations in using life cycle assessment to evaluate the direct environmental and human health impacts from emissions of nanomaterials themselves. This is due to the limited life cycle inventory data and life cycle impact assessment models currently available for describing the fate, exposure and effects of engineered nanomaterials in the environment. Specifically, current life cycle impact assessment methodologies do not include characterization factors for nanomaterials. Engineered nanomaterials may be emitted throughout the life cycle of a product, for example, in the occupational setting where there may be constant interaction between workers and large volumes of loose nano-powders. This paper presents a dynamic model that is intended for use in life cycle impact assessment methods to quantify the fate, exposure and human health effects of engineered nanomaterials. Using the case-study of nano-TiO2 emissions in the indoor workplace, nano-specific life cycle assessment characterization factors are presented. Compared to previously published steady-state models, the results of the current study demonstrate a much lower exposure potential, expressed as the ‘retained’-intake fraction of nano-TiO2 in the lung over the total emitted amount. Furthermore, the results indicate that smaller emissions lead to greater fractional deposition. Thus, an inverse relationship between the total indoor air emissions of nano-TiO2, and the resulting magnitude of the characterization factor was seen.
... Finally, other reference values (DNEL) for selected ENMs (e.g. fullerene, CNTs, silver, TiO 2 ) were proposed by experts [Stone et al., 2010]. It must be noted that NRVs, as the majority of the proposed OELs for ENPs, used number concentration as reference metric (although some of the proposed OELs are also expressed as mass concentration). ...
Article
An increasing number of studies are indicating that the health risk deriving from exposure to engineered nanomaterials (ENMs) and nanoparticles (ENPs) is not adequately addressed by conventional exposure evaluation methods and strategies. The global aim of this study was to carry out a review of the state-of-the-science of ENMs occupational exposure assessment, with particular concern on the main problems related to ENPs exposure assessment. Original articles and reviews in principal databases of scientific literature were included in this paper; grey literature (released by qualified regulatory agencies and scientific organizations) was also taken into consideration. The paper discusses in particular the main problems found in ENPs exposure assessment, which have been generally identified in: (i) the choice of a proper dosimetric for exposure assessment, (ii) the lack of adequate and reliable measurement techniques, (iii) the need of a harmonized monitoring strategy, (iv) the need of an effective method for the distinction of ENPs from background particles and (v) the difficulties to compare ENPs exposure data with proper Occupational Exposure Limits. On the basis of the considered existing approaches, some key issues related to exposure assessment strategies, derived from direct on-field exposure are then discussed, as well as some identified priorities in the field of ENPs exposure assessment. In conclusion, most of the existing techniques and strategies for occupational exposure assessment to ENPs and ENMs require adjustment, and significant methodological gaps need to be reduced. The rational use of risk management strategies and the application of specifically-developed Occupational Exposure Limits are crucial to mitigate the risk posed for ENPsexposed workers. The development and harmonization of appropriate exposure assessment strategies and techniques and risk management approaches represent an essential step toward developing health and safety standards for ENPs.
... local exhaust ventilation with mobile HEPA-filtered inlets to be placed in correspondence with the potential sources of ENPs) is recommended and should contribute to a further lowering of occupational exposures, workplace contamination levels and high-level transient exposure peaks. (DNEL) for nano-TiO 2 (17 μg/m 3 ; 40 h/week weighted average standard) has been proposed as outcomes of the ENRHES project (Stone et al., 2010 ). Considering these values, workers were attended to be exposed to ENPs levels ( ...
Article
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Limited data are available regarding occupational exposure assessment to nano-sized titanium dioxide (nano-TiO2). The objective of this study is to assess the occupational exposure of workers engaged in the application of nano-TiO2 onto concrete building materials, by means of a multi-metric approach (mean diameter, number, mass and surface area concentrations). The measurement design consists of the combined use of (i) direct-reading instruments to evaluate the total particle number concentrations relative to the background concentration and the mean size-dependent characteristics of particles (mean diameter and surface area concentration) and to estimate the 8-h time-weighted average (8-h TWA) exposure to nano-TiO2 for workers involved in different working tasks; and (ii) filter-based air sampling, used for the determination of size-resolved particle mass concentrations. A further estimation was performed to obtain the mean 8-h TWA exposure values expressed as mass concentrations (µg nano-TiO2/m3). The multi-metric characterization of occupational exposure to nano-TiO2 was significantly different both for different work environments and for each work task. Generally, workers were exposed to engineered nanoparticles (ENPs; <100 nm) mean levels lower than the recommended reference values and proposed occupational exposure limits (40,000 particle/cm3; 300 µg/m3) and relevant exposures to peak concentration were not likely to be expected. The estimated 8-h TWA exposure showed differences between the unexposed and exposed subjects. For these last, further differences were defined between operators involved in different work tasks. This study provides information on nano-TiO2 number and mass concentration, size distribution, particles diameter and surface area concentrations, which were used to obtain work shift-averaged exposures.
... According to our results, ZnO is the ENM of highest concern. ZnO exhibited very high toxicity in all the compartments in accordance with Stone et al. (2009) and Aschberger et al. (2011). Additionally, the predicted exposure concentrations for the environment were also high in the mg/L (water), mg/kg (soil), and mg/kg (sediment) range (Sun et al., 2014). ...
Article
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Nano-silica, the engineered nanomaterial with one of the largest production volumes, has a wide range of applications in consumer products and industry. This study aimed to quantify the exposure of nano-silica to the environment and to assess its risk to surface waters. Con-centrations were calculated for four environmental (air, soil, surface water, sediments) and two technical compartments (wastewater, solid waste) for the EU and Switzerland using probabilistic material flow modeling. The corresponding median concentration in surface waters is predicted to be 0.12 µg/L in the EU (0.053-3.3 µg/L, 15/85% quantiles). The con-centrations in sediments in the complete sedimentation scenario were found to be the larg-est among all environmental compartments, with a median annual increase of 0.43 mg/kg·y in the EU (0.19-12 mg/kg·y, 15/85% quantiles). Moreover, probabilistic species sensitivity distributions (PSSD) were computed and the risk of nano-silica in surface waters was quanti-fied by comparing the predicted environmental concentration (PEC) with the predicted no-effect concentration (PNEC) distribution, which was derived from the cumulative PSSD. This assessment suggests that nano-silica currently poses no risk to aquatic organisms in surface waters. Further investigations are needed to assess the risk of nano-silica in other environ-mental compartments, which is currently not possible due to a lack of ecotoxicological data.
... However, all of these have concluded that due to limited data and extensive uncertainties, it is not possible based on readily available information to complete full RAs for regulatory decision-making for the NM investigated and their results are to be considered as preliminary. Among other challenges, there is a lack of measured exposure data for NM, lack of validated exposure estimation models, extensive uncertainties within characterizing NM, applicability of current test guidelines as well as a lack of (eco)toxicological studies in a variety of species (Baun et al. 2009; SCENIHR 2009; Stone et al. 2010 ). This means that meaningful hazard identification and hence dose–response, as well as exposure assessments are difficult to complete for most NM. ...
... According to our results, ZnO is the ENM of highest concern. ZnO exhibited very high toxicity in all the compartments in accordance with Stone et al. (2009) and Aschberger et al. (2011). Additionally, the predicted exposure concentrations for the environment were also high in the mg/L (water), mg/kg (soil), and mg/kg (sediment) range (Sun et al., 2014). ...
Article
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The environmental risks of five engineered nanomaterials (nano-TiO2, nano-Ag, nano-ZnO, CNT, and fullerenes) were quantified in water, soils, and sediments using probabilistic Species Sensitivity Distributions (pSSDs) and probabilistic predicted environmental concentrations (PECs). For water and soil, enough ecotoxicological endpoints were found for a full risk characterization (between 17 and 73 data points per nanomaterial for water and between 4 and 20 for soil) whereas for sediments, the data availability was not sufficient. Predicted No Effect Concentrations (PNECs) were obtained from the pSSD and used to calculate risk characterization ratios (PEC/PNEC). For most materials and environmental compartments, exposure and effect concentrations were separated by several orders of magnitude. Nano-ZnO in freshwaters and nano-TiO2 in soils were the combinations where the risk characterization ratio was closest to one, meaning that these are compartment/ENM combinations to be studied in more depth with the highest priority. The probabilistic risk quantification allows us to consider the large variability of observed effects in different ecotoxicological studies and the uncertainty in modeled exposure concentrations. The risk characterization results presented in this work allows for a more focused investigation of environmental risks of nanomaterials by consideration of material/compartment combinations where the highest probability for effects with predicted environmental concentrations is likely.
... Another source of uncertainty is that exposure to dust and toxic substances is measured and expressed as mass per unit volume (typically mg/m -3 ). However, the effects of nanoparticles (NPs) seem to be more closely related to surface area than to mass (STONE, 2009). ...
Article
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Nanoparticles are being explored for biomedical applications in diagnostics and therapeutics. However, biocompatibility, toxicity and cellular entry ability are critical factors that will determine the utility of nanoparticles in clinical applications. “Omics” technologies can provide powerful tools that are sensitive and complementary for the study of molecular toxicology and for biomedical applications of nanomaterials. Specifically, proteomics could elucidate mechanisms of action and contribute to studies on how nanomaterials affect protein expression in tissues and organs, metabolic pathways, signal transduction mechanisms and target molecules. The objective of this review is to present a small approach about “omics” technologies applied to the study of the effect of carbon nanomaterials in the cell.
... Gold has been considered to be of low toxicity for organisms, but, as mentioned before, at a nanoscale it greatly increases the activity of the substances as a result of the conformation of the atoms which makes them highly exposed (Auffan et al., 2009;Perreault et al., 2012a). Ecotoxicity studies on AuNPs have been scarce till recent years (Stone, 2009). In general, AuNPs toxicity seems to be lower than that of AgNPs for aquatic organisms (Joubert et al., 2013). ...
... Dermal exposure studies to date have not yet demonstrated any penetration or toxicity via this route. In relation to environmental exposure, the fate and behaviour of TiO 2 following release into the environment also remains uncertain to date [111] .Based upon the evidence relating to potential hazard to date, it is advisable that procedures for manufacturing, use and waste management should avoid uncontrolled or accidental release of TiO 2 nanoparticles and subsequent exposure to humans or the environment. ...
Article
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Recent interest and studies in environmental photo-chemistry, in natural photosynthesis, and chemical methods for solar energy transformations has contributed greatly to our knowledge and understanding of the various phenomena related to both photo-chemistry and catalysis. As an emerging nanotechnology come together with the chemical mechanisms of photo-catalysis, the photo-catalytic nanoparticle titanium dioxide offers a new meaning of remediation and degradation on volatile organic compounds in the aqueous and airs streams. In this chapter we discuss about application of photocatalysis in environment like biological contamination, air purification, water disinfection, hazardous waste remediation, water purification, self-clean buildings, deodorizing, anti-bacterial action, anti-fogging resolving cleaning action etc.
... It is also believed that ENP could interact with biological structures of similar size (such as DNA and proteins) or biologically active molecules (Nel et al., 2009). Until now, the epistemic uncertainty in regard to the EHS/S risks of ENP has not been resolved (Chaudhry et al., 2008; Stone et al., 2009; NSET & CoT, 2011; Som et al., 2011). The immense variety in properties of ENP pose a challenge for toxicological and environmental risk assessment. ...
... The use of engineered nanoparticles (ENPs) in a range of applications and consumer products is rapidly increasing [1,2]. However, due to their relative novelty, little has been done to assess the risks to the human health and the environment, raising a variety of concerns related to the use of nanomaterials [3][4][5][6]. ...
Article
Different approaches to the most relevant and recent studies and applications of inductively coupled plasma mass spectrometry (ICP-MS) applied to the analysis of natural and engineered nanoparticles in the environment are described. Usually several separation methods like polyacrylamide gel electrophoresis (PAGE), field-flow fractionation (FFF) and size exclusion chromatography (SEC) are used prior to the mass spectrometric measurements. In many cases the use of these hyphenated techniques provides important methodologies to know the bioavailability, mobility and toxicity of elements in life and environmental sciences. Alternatively, the capabilities of the single particle detection by ICP-MS (SD-ICP-MS) for the selective identification, characterization and determination of engineered nanoparticles will be also discussed.
... mple, a target level for one worker to develop a cancer in a population of 10 6 (million) workers per year (incident 10 −6 ) or one worker to get sensitized in a population of 100 workers per year, related to the exposure to the specific substance. For a few frequently used MNMs, exercises have been carried out to derive a health-based OEL or DNEL. Stone et al. (2010) derived provisional DNELs for some frequently used nanomaterials by using the methodology as described by REACH. P.S. illustrated the preference of NIOSH for health-based limit values by explaining the efforts to derive a recommended exposure limit (REL) for carbon nanotubes (CNTs) (NIOSH, 2010) and titanium dioxide (TiO 2 ) (NIOSH, 201 ...
Article
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This article summarizes the outcome of the discussions at the international workshop on nano reference values (NRVs), which was organized by the Dutch trade unions and employers' organizations and hosted by the Social Economic Council in The Hague in September 2011. It reflects the discussions of 80 international participants representing small- and medium-size enterprises (SMEs), large companies, trade unions, governmental authorities, research institutions, and non-governmental organizations (NGOs) from many European countries, USA, India, and Brazil. Issues that were discussed concerned the usefulness and acceptability of precaution-based NRVs as a substitute for health-based occupational exposure limits (OELs) and derived no-effect levels (DNELs) for manufactured nanoparticles (NPs). Topics concerned the metrics for measuring NPs, the combined exposure to manufactured nanomaterials (MNMs) and process-generated NPs, the use of the precautionary principle, the lack of information about the presence of nanomaterials, and the appropriateness of soft regulation for exposure control. The workshop concluded that the NRV, as an 8-h time-weighted average, is a comprehensible and useful instrument for risk management of professional use of MNMs with a dispersible character. The question remains whether NRVs, as advised for risk management by the Dutch employers' organization and trade unions, should be under soft regulation or that a more binding regulation is preferable.
Conference Paper
In order to increase thermal performance and reduce as much as possible, energy consumption in refrigeration systems, continuous research is carried out to investigate the importance of nanotechnology by reviewing papers on the effect of the addition of nano-lubricants to refrigerants in the compressors. This research seeks to review the roles of nanotechnology in the development of nano-lubricant for refrigeration systems, especially from agricultural sources. Also, the literature works on basic concepts as well as previous works based on the effect of different lubricants on refrigerator systems to attain a better understanding of this study.
Chapter
Nanotechnology is the latest development in science, where design, construction and applications of various particles involve at least one dimension in nanometers. The nanotechnology has been utilized in many of the scientific and societal disciplines including electronics, medicine, materials science and many more. It has also influenced the broader fields like civil engineering as well as the sub-disciplines including transportation, structural, geotechnical, water resources and environmental engineering. The current focus of the researchers in transportation field is to develop the materials for sustainable transportation facilities, by using the concepts of nanotechnology. The chapter is concerned with the literature review of potential applications of the nanotechnology in transportation engineering including safety, durability, sustainability and economy. The practical applications of the nanotechnology and nanomaterials shall prove to be an asset in transportation engineering.
Chapter
Full-text available
Nanotechnology is the latest development in science, where design, construction and applications of various particles involve at least one dimension in nanometers. The nanotechnology has been utilized in many of the scientific and societal disciplines including electronics, medicine, materials science and many more. It has also influenced the broader fields like civil engineering as well as the sub-disciplines including transportation , structural, geotechnical, water resources and environmental engineering. The current focus of the researchers in transportation field is to develop the materials for sustainable transportation facilities, by using the concepts of nanotechnology. The chapter is concerned with the literature review of potential applications of the nano-technology in transportation engineering including safety, durability, sustainability and economy. The practical applications of the nanotechnology and nanomaterials shall prove to be an asset in transportation engineering.
Technical Report
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This state-of-the-science review was undertaken to identify fate and transport models and alternative modeling approaches that could be used to predict exposure to engineered nanomaterials (ENMs) released into the environment, specifically, for aquatic systems. The development of modeling frameworks that represent the unique complexities of ENM behavior in the environment is in its infancy, and a critical mass of researchers actively engaged in model development efforts has yet to be achieved. Further, it is widely recognized that there are many obstacles to model development and, in general, to conducting environmental risk assessments of ENMs that provide meaningful information for risk managers. Nevertheless, the U.S. Environmental Protection Agency (EPA) will be required to manage potential risks across the life cycle of ENMs, from production through the disposition of wastewaters and residuals containing ENMs. Therefore, this state-of-the-science review included traditional modeling frameworks as well as approaches that are considered relatively new to environmental modeling science and risk management (e.g., adaptive management, multi-criteria decision analysis). In essence, this review sought to answer five basic questions: 1. What models and approaches have been used successfully to simulate nanomaterial behavior in environmental systems? 2. What models and approaches cannot be used to predict exposures to ENMs in ecosystems? 3. What models and approaches can be used in the near term, and what types of predictions can be supported by available models? 4. What techniques can be used to address uncertainties and support risk management decisions in the near term given obvious gaps in information? 5. What does the state-of-the-science suggest with respect to long-term research goals that can be undertaken to improve fate and transport modeling tools for ENMs?
Article
For the last 10 years, engineered nanomaterials (ENMs) have raised interest to industrials due to their properties. They are present in a large variety of products from cosmetics to building materials through food additives, and their value on the market was estimated to reach $3 trillion in 2014 (Technology Strategy Board 2009). TiO2 NMs represent the second most important part of ENMs production worldwide (550-5500 t/year). However, a gap of knowledge remains regarding the fate and the effects of these, and consequently, impact and risk assessments are challenging. This is due to difficulties in not only characterizing NMs but also in selecting the NM properties which could contribute most to ecotoxicity and human toxicity. Characterizing NMs should thus rely on various analytical techniques in order to evaluate several properties and to crosscheck the results. The aims of this review are to understand the fate and effects of TiO2 NMs in water, sediment, and soil and to determine which of their properties need to be characterized, to assess the analytical techniques available for their characterization, and to discuss the integration of specific properties in the Life Cycle Assessment and Risk Assessment calculations. This study underlines the need to take into account nano-specific properties in the modeling of their fate and effects. Among them, crystallinity, size, aggregation state, surface area, and particle number are most significant. This highlights the need for adapting ecotoxicological studies to NP-specific properties via new methods of measurement and new metrics for ecotoxicity thresholds.
Article
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.
Article
Purpose Numerous publications in the last years stressed the growing importance of nanotechnology in our society, highlighting both positive as well as in the negative topics. Life cycle assessment (LCA) is amongst the most established and best-developed tool in the area of product-related assessment. In order to use this tool in the area of nanotechnology, clear rules of how emissions of nanomaterials should be taken into account on the level of life cycle inventory (LCI) modelling are required—i.e. what elements and properties need to be reported for an emission of a nanomaterial. The objective of this paper is to describe such a framework for an adequate and comprehensive integration of releases of nanomaterials. Methods With a three-step method, additional properties are identified that are necessary for an adequate integration of releases of nanomaterials into LCA studies. Result and discussion In the first step, a comprehensive characterisation of the release of a nanomaterial is compiled—based on reviewing scientific publications, results from expert workshops and publications from public authorities and international organisations. In the second step, this comprehensive overview is refined to a list containing only those properties that are effectively relevant for LCA studies—i.e. properties that influence the impacts in the areas of human toxicity and ecotoxicity, respectively. For this, an academic approach is combined with a second, more practical, view point, resulting together in a prioritisation of this list of properties. Finally, in a third step, these findings are translated into the LCA language—by showing how such additional properties could be integrated into the current LCA data formats for a broader use by the LCA community. Conclusions As a compromise between scholarly knowledge and the (toxicological) reality, this paper presents a clear proposal of an LCI modelling framework for the integration of releases of nanomaterials in LCA studies. However, only the broad testing of this framework in various situations will show if the suggested simplifications and reductions keep the characterisation of releases of nanomaterials specific enough and/or if assessment is accurate enough. Therefore, a next step has to come from the impact assessment, by the development of characterisation factors as a function of size and shape of such releases.
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