Chemicals - Nanomaterials

Title

Daily Newspapers’ Views on Nanotechnology in Slovenia

Reference

Science Communication
December 20, 2011 1075547011427974

Author(s)

Blanka Groboljsek, Franc Mali

Study type

Peer Review Journal    

Abstract

This article investigates how nanotechnology is presented and framed inSlovenian national newspapers. The focus is on the mass media’s influence on citizens’ perceptions of the social implications of nanotechnological progress. An empirical analysis of newspaper coverage of nanotechnology in Slovenia between 2004 and 2009 suggests that Slovenian newspapers are in an early stage of covering nanotechnology issues since they emphasize the positive aspects and scientific interpretations. Additional in-depth interviews with nanotechnologists reveal considerable dissatisfaction with the level and quality of the media’s reporting of the issue of nanotechnology in Slovenia.

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials
Environmental information services >> Environmental communication >> Stakeholder/public engagement

Keywords

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Selected for Science for Environment Policy News Alert

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http://scx.sagepub.com/content/early/2011/11/28/1075547011427974.abstract?papetoc
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blanka.groboljsek@fdv.uni-lj.si

Title

Titanium Dioxide Nanoparticles in Food and Personal Care Products

Reference

Weir, A., Westerhoff, P., Fabricius, L., Hristovski, K., von Goetz, N.,

Author(s)

Environmental Science & Technology  46 (4), 2242-2250.

Study type

Peer Review Journal    

Abstract

Titanium dioxide is a common additive in many food, personal care, and other consumer products used by people, which after use can enter the sewage system and, subsequently, enter the environment as treated effluent discharged to surface waters or biosolids applied to agricultural land, incinerated wastes, or landfill solids. This study quantifies the amount of titanium in common food products, derives estimates of human exposure to dietary (nano-) TiO2, and discusses the impact of the nanoscale fraction of TiO2 entering the environment. The foods with the highest content of TiO2 included candies, sweets, and chewing gums. Among personal care products, toothpastes and select sunscreens contained 1% to >10% titanium by weight. While some other crèmes contained titanium, despite being colored white, most shampoos, deodorants, and shaving creams contained the lowest levels of titanium (<0.01 μg/mg). For several high-consumption pharmaceuticals, the titanium content ranged from below the instrument detection limit (0.0001 μg Ti/mg) to a high of 0.014 μg Ti/mg. Electron microscopy and stability testing of food-grade TiO2 (E171) suggests that approximately 36% of the particles are less than 100 nm in at least one dimension and that it readily disperses in water as fairly stable colloids. However, filtration of water solubilized consumer products and personal care products indicated that less than 5% of the titanium was able to pass through 0.45 or 0.7 μm pores. Two white paints contained 110 μg Ti/mg while three sealants (i.e., prime coat paint) contained less titanium (25 to 40 μg Ti/mg). This research showed that, while many white-colored products contained titanium, it was not a prerequisite. Although several of these product classes contained low amounts of titanium, their widespread use and disposal down the drain and eventually to wastewater treatment plants (WWTPs) deserves attention. A Monte Carlo human exposure analysis to TiO2 through foods identified children as having the highest exposures because TiO2 content of sweets is higher than other food products and that a typical exposure for a US adult may be on the order of 1 mg Ti per kilogram body weight per day. Thus, because of the millions of tons of titanium-based white pigment used annually, testing should focus on food-grade TiO2 (E171) rather than that adopted in many environmental health and safety tests (i.e., P25), which is used in much lower amounts in products less likely to enter the environment (e.g., catalyst supports, photocatalytic coatings).

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials
Environment and health >> Health risks >> Product safety

Keywords

Entry Source:

Selected for Science for Environment Policy News Alert

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http://pubs.acs.org/doi/abs/10.1021/es204168d
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p.westerhoff@asu.edu.

Title

Copper Oxide Nanoparticle Mediated DNA Damage in Terrestrial Plant Models

Reference

Environmental Science & Technology 46 (3), 1819-1827.

Author(s)

Atha, D.H., Wang, H., Petersen, E.J., Cleveland, D., Holbrook, R.D., Jaruga, P., Dizdaroglu, M., Xing, B., Nelson, B.C.,

Study type

Peer Review Journal   

Abstract

Engineered nanoparticles, due to their unique electrical, mechanical, and catalytic properties, are presently found in many commercial products and will be intentionally or inadvertently released at increasing concentrations into the natural environment. Metal- and metal oxide-based nanomaterials have been shown to act as mediators of DNA damage in mammalian cells, organisms, and even in bacteria, but the molecular mechanisms through which this occurs are poorly understood. For the first time, we report that copper oxide nanoparticles induce DNA damage in agricultural and grassland plants. Significant accumulation of oxidatively modified, mutagenic DNA lesions (7,8-dihydro-8-oxoguanine; 2,6-diamino-4-hydroxy-5-formamidopyrimidine; 4,6-diamino-5-formamidopyrimidine) and strong plant growth inhibition were observed for radish (Raphanus sativus), perennial ryegrass (Lolium perenne), and annual ryegrass (Lolium rigidum) under controlled laboratory conditions. Lesion accumulation levels mediated by copper ions and macroscale copper particles were measured in tandem to clarify the mechanisms of DNA damage. To our knowledge, this is the first evidence of multiple DNA lesion formation and accumulation in plants. These findings provide impetus for future investigations on nanoparticle-mediated DNA damage and repair mechanisms in plants.

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials

Keywords

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Shortlisted for Science for Environment Policy News Alert

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http://pubs.acs.org/doi/abs/10.1021/es202660k
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yant.nelson@nist.gov

Title

Occurrence of Aerosol-Bound Fullerenes in the Mediterranean Sea Atmosphere

Reference

Environmental Science & Technology 46 (3), 1335-1343.

Author(s)

Sanches, J., Berrojalbiz, N., Caballero, G., Dachs, J., Farre, M., Barcelo, D

Study type

Peer Review Journal    

Abstract

This work describes the assessment of a selection of fullerenes including C60 and C70 fullerene, N-methylfulleropyrrolidine, C60 pyrrolidine tris-acid ethyl ester, [6,6]-Phenyl-C61 butyric acid butyl ester and [6,6]-Thienyl C61 butyric acid methyl ester, in airborne particulate from the Mediterranean Sea collected during two sampling campaigns from Barcelona to Istanbul and Alexandria, respectively. The analysis of the samples was carried out using a new method based on liquid chromatography coupled to mass spectrometry (LC-MS) presenting sensitivities between 5.4 and 20.9 pg/m3. A total number of 43 samples covering the different basins of Mediterranean Sea were analyzed. Fullerenes were detected in all analyzed samples and quantifiable concentrations were found in 28 of the analyzed samples. The median of C60 and C70 fullerenes aerosol phase concentrations were 0.06 ng/m3 and 0.48 ng/m3 respectively for the Mediterranean Sea atmosphere. C70 fullerene was the most frequently detected compound and also it was found in the higher concentrations for most samples, reaching 233.8 ng/m3. The modeled back-trajectories disclose that those samples with higher concentrations of fullerenes were related to air masses which had been circulating over regions with an intense industrial activity, but the variability of the C70/C60 ratio suggests multiple different sources. These results are related to the incidental emissions from urban and industrial development, underpinning the need of studying the possible risks associated to carbon nanoparticles in the environment and the need of evaluating the possible consequences of their ubiquitous occurrence.

Policy theme(s)

Air pollution >> Source of emissions >> Industrial emissions
Chemicals >> Pollutants/hazardous substances >> Nanomaterials

Keywords

Entry Source:

Selected for Science for Environment Policy News Alert

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http://pubs.acs.org/doi/abs/10.1021/es200758m
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mfuqam@cid.csic.es

Title

Impact of engineered nanomaterials on health

Reference

EASAC and JRC joint report
September 2011

Author(s)

EASAC and JRC

Study type

Report

Abstract

This policy report is the result of the first strategic liaison between the JRC and EASAC and provides independent, cross-referenced, science-based analysis of the impact of nanomaterials on human health. Our report is directed at European and national policy-makers and citizens. Nanomaterials have the potential to play a major role in European innovation, economic growth and industrial
competitiveness. In order to capitalise on this technology and reap the promised benefits, the EU must ensure the appropriate framework for its success. A key element in this regard concerns a harmonised assessment of the safety of nanomaterials and this requires a strengthened dialogue between policy-makers and scientists.

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials
Environment and health >> Health risks >> Product safety

Keywords

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Selected for Science for Environment Policy News Alert

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http://www.easac.eu/fileadmin/PDF_s/EASAC_Nanosafety_Report_WEB.pdf
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www.easac.eu/

Title

Acute and reproductive toxicity of nano-sized metal oxides (ZnO and TiO2) to earthworms (Eisenia fetida)

Reference

J. Environ. Monit., 2011
DOI:10.1039/C1EM10497G

Author(s)

Jaclyn E. Cañas, Beibei Qi, Shibin Li, Jonathan D. Maul, Stephen B. Cox, Sriya Das and Micah J. Green

Study type

Peer Review Journal

Abstract

An increase in nanomaterial applications will likely lead to an increased probability of environmental exposures, raising concerns regarding the safety of these materials. Recent studies have indicated that manufactured nanomaterials, such as metal oxides, have the potential to be harmful to aquatic and terrestrial organisms. The majority of nano-metal oxide research addressing potential toxicological issues has been focused in aquatic environments with very little terrestrial data. This study characterized the acute and reproductive toxicity of zinc oxide (ZnO) and titanium dioxide (TiO2) to earthworms (Eisenia fetida) in a terrestrial system. Following a 14 d exposure, nano-sized ZnO on filter paper was acutely toxic to E. fetida, while nano-sized TiO2 did not exhibit acute toxicity. In contrast, neither nano-sized ZnO nor TiO2 exhibited acute toxicity to earthworms in sand. Both nano-sized ZnO and TiO2, following a 4 week exposure, caused reproductive effects in earthworms in artificial soil. Overall, nano-sized ZnO exhibited greater toxicity than nano-sized TiO2 in Eisenia fetida.

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials
Chemicals >> Impacts >> Ecosystem impacts
Soil >> Threats to soil >> Soil contamination

Keywords

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

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http://pubs.rsc.org/en/content/articlelanding/2011/em/c1em10497g
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jaclyn.canas@tiehh.ttu.edu

Title

Assessing the potential exposure risk and control for airborne titanium dioxide and carbon black nanoparticles in the workplace

Reference

Environmental Science and Pollution Research
2011 DOI: 10.1007/s11356-011-0447-y

Author(s)

Min-Pei Ling, Chia-Pin Chio, Wei-Chun Chou, Wei-Yu Chen, Nan-Hung Hsieh, Yi-Jun Lin and Chung-Min Liao 

Study type

Peer Review Journal

Abstract

Purpose  
This study assessed the potential exposure risks for workers in the workplace exposed to airborne titanium dioxide nanoparticles (TiO₂-NPs) and carbon black nanoparticles (CB-NPs). The risk management control strategies were also developed for the NP engineering workplace.
Methods  
The method used in this study was based on the integrated multiple-path particle dosimetry model to estimate the cumulative dose of nanoparticles (NPs) in the human lung. The study then analyzed toxicological effects such as pulmonary cytotoxicity and inflammation and evaluated the health risk associated with exposure to NPs in the workplace. Risk control measures such as the use of ventilating systems and N95 respirator protection are also discussed.
Results and discussion  
This study found that: (1) the cumulative dose of CB-NPs was greater than that of TiO₂-NPs in human lungs; (2) there is a potential health risk to workers exposed to TiO₂-NPs and CB-NPs in the absence of control measures in the workplace, with higher health risks associated with CB-NPs than TiO₂-NPs; and (3) the use of a ventilating system and an N95 respirator offers greater protection in the workplace and significantly reduces the health risks associated with NP exposure.
Conclusion  
The present risk management control strategy suggests that the most effective way to reduce airborne NPs is to incorporate the use of a ventilating system combined with N95 respirator protection. This will enable the concentrations of TiO₂-NPs and CB-NPs to be reduced to acceptable exposure levels.

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials
Air pollution >> Impact of emissions >> Health impacts
Risk assessment >> Hazards >> Hazardous substances

Keywords

Titanium dioxide, Carbon black, Nanoparticles, Workplace, Risk assessment

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

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http://www.springerlink.com/content/ytu3276v4w5534k8
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cmliao@ntu.edu.tw

Title

Analysis of currently available data for characterising the risk of engineered nanomaterials to the environment and human health — Lessons learned from four case studies

Reference

Environment International
Volume 37, Issue 6, August 2011, Pages 1143-1156
Special Issue: Environmental Fate and Effects of Nanoparticles

Author(s)

Karin Aschberger, Christian Micheletti, Birgit Sokull-Klüttgen and Frans M. Christensen

Study type

Peer Review Journal

Abstract

Production volumes and the use of engineered nanomaterials in many innovative products are continuously increasing, however little is known about their potential risk for the environment and human health.
We have reviewed publicly available hazard and exposure data for both, the environment and human health and attempted to carry out a basic risk assessment appraisal for four types of nanomaterials: fullerenes, carbon nanotubes, metals, and metal oxides (ENRHES project 2009). This paper presents a summary of the results of the basic environmental and human health risk assessments of these case studies, highlighting the cross cutting issues and conclusions about fate and behaviour, exposure, hazard and methodological considerations.
The risk assessment methodology being the basis for our case studies was that of a regulatory risk assessment under REACH (ECHA, 2008), with modifications to adapt to the limited available data. If possible, environmental no-effect concentrations and human no-effect levels were established from relevant studies by applying assessment factors in line with the REACH guidance and compared to available exposure data to discuss possible risks. When the data did not allow a quantitative assessment, the risk was assessed qualitatively, e.g. for the environment by evaluating the information in the literature to describe the potential to enter the environment and to reach the potential ecological targets.
Results indicate that the main risk for the environment is expected from metals and metal oxides, especially for algae and Daphnia, due to exposure to both, particles and ions. The main risks for human health may arise from chronic occupational inhalation exposure, especially during the activities of high particle release and uncontrolled exposure. The information on consumer and environmental exposure of humans is too scarce to attempt a quantitative risk characterisation.
It is recognised that the currently available database for both, hazard and exposure is limited and there are high uncertainties in any conclusion on a possible risk. The results should therefore not be used for any regulatory decision making. Likewise, it is recognised that the REACH guidance was developed without considering the specific behaviour and the mode of action of nanomaterials and further work in the generation of data but also in the development of methodologies is required.

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials
Risk assessment >> Risk assessment methodologies

Keywords

Nanomaterials; Toxicity; Environment; Exposure; Hazard; Risk

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

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http://www.sciencedirect.com/science/article/pii/S0160412011000365
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karin.aschberger@ec.europa.eu

Title

How to assess exposure of aquatic organisms to manufactured nanoparticles?

Reference

Environment International
Volume 37, Issue 6, August 2011, Pages 1068-1077

Author(s)

Joris T.K. Quik, Jan Arie Vonk, Steffen Foss Hansen, Anders Baun and Dik Van De Meent

Study type

Peer Review Journal

Abstract

Ecological risk of chemicals is measured by the quotient of predicted no-effect concentrations and predicted exposure concentrations, which are hard to assess for manufactured nanomaterials (NMs). This paper proposes modifications to currently used models, in order to make them suitable for estimating exposure concentrations of NMs in the aquatic environment. We have evaluated the adequacy of the current guidance documents for use with NMs and conclude that nano-specific fate processes, such as sedimentation and dissolution need to be incorporated. We have reviewed the literature on sedimentation and dissolution of NMs in environmentally relevant systems. We deduce that the overall kinetics of water–sediment transport of NMs should be close to first order. The lack of data on dissolution of NMs under environmentally realistic conditions calls for a pragmatic decision on which rates to be used in modeling. We find that first order removal kinetics for dissolution seems adequate. Based on limited data from literature, probable removal rates range from 0 to 10-4 s-1 for sedimentation, and from 0 to 10-5 s-1 for dissolution. Further experimental data at environmentally relevant conditions for sedimentation and dissolution of NMs is needed.

Policy theme(s)

Biodiversity >> Threats to biodiversity >> Human impacts
Chemicals >> Pollutants/hazardous substances >> Nanomaterials
Risk assessment >> Hazards >> Hazardous substances

Keywords

Nanomaterials, Sedimentation, Dissolution, Exposure assessment, Aquatic environment

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

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http://www.sciencedirect.com/science/article/pii/S0160412011000304
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joris.quik@rivm.nl

Title

Prospective Environmental Life Cycle Assessment of Nanosilver T-Shirts

Reference

Environ. Sci. Technol., 2011, 45 (10), pp 4570-4578
DOI: 10.1021/es2001248

Author(s)

Tobias Walser, Evangelia Demou, Daniel J. Lang, and Stefanie Hellweg

Study type

Peer Review Journal

Abstract

A cradle-to-grave life cycle assessment (LCA) is performed to compare nanosilver T-shirts with conventional T-shirts with and without biocidal treatment. For nanosilver production and textile incorporation, we investigate two processes: flame spray pyrolysis (FSP) and plasma polymerization with silver co-sputtering (PlaSpu). Prospective environmental impacts due to increased nanosilver T-shirt commercialization are estimated with six scenarios. Results show significant differences in environmental burdens between nanoparticle production technologies: The 'cradle-to-gate' climate footprint of the production of a nanosilver T-shirt is 2.70 kg of CO(2)-equiv (FSP) and 7.67-166 kg of CO(2)-equiv (PlaSpu, varying maturity stages). Production of conventional T-shirts with and without the biocide triclosan has emissions of 2.55 kg of CO(2)-equiv (contribution from triclosan insignificant). Consumer behavior considerably affects the environmental impacts during the use phase. Lower washing frequencies can compensate for the increased climate footprint of FSP nanosilver T-shirt production. The toxic releases from washing and disposal in the life cycle of T-shirts appear to be of minor relevance. By contrast, the production phase may be rather significant due to toxic silver emissions at the mining site if high silver quantities are required.

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials

Keywords

N/A

Entry Source:

N/A

Referred to in EC doc:

Shortlisted for Science for Environment Policy News Alert

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http://pubs.acs.org/doi/abs/10.1021/es2001248
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tobias.walser@ifu.baug.ethz.ch

Title

Reference

J. Environ. Monit., 2011, 13, 822-828
DOI: 10.1039/C0EM00611D

Author(s)

Wenchao Du, Yuanyuan Sun, Rong Ji, Jianguo Zhu, Jichun Wu and Hongyan Guo

Study type

Peer Review Journal

Abstract

The properties of nanoparticles and their increased use have raised concerns about their possible harmful effects within the environment. Most studies on their effects have been in aqueous systems. Here we investigated the effect of TiO2 and ZnO nanoparticles on wheat growth and soil enzyme activities under field conditions. Both of the nanoparticles reduced the biomass of wheat. The TiO2 nanoparticles were retained in the soil for long periods and primarily adhered to cell walls of wheat. The ZnO nanoparticles dissolved in the soil, thereby enhancing the uptake of toxic Zn by wheat. The nanoparticles also induced significant changes in soil enzyme activities, which are bioindicators of soil quality and health. Soil protease, catalase, and peroxidase activities were inhibited in the presence of the nanoparticles; urease activity was unaffected. The nanoparticles themselves or their dissolved ions were clearly toxic for the soil ecosystem.

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials
Agriculture >> Agricultural management >> Soil management
Soil >> Threats to soil >> Soil contamination

Keywords

N/A

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

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http://pubs.rsc.org/en/Content/ArticleLanding/2011/EM/c0em00611d
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hyguo@nju.edu.cn

Title

Environmental and health effects of nanomaterials in nanotextiles and
façade coatings

Reference

Environment International (2011)
Volume 37, Issue 6, August 2011, Pages 1131-1142

Author(s)

Claudia Som, Peter Wick b, Harald Krug b, Bernd Nowack

Study type

Peer Review Journal

Abstract

Engineered nanomaterials (ENM) are expected to hold considerable potential for products that offer improved or novel functionalities. For example, nanotechnologies could open the way for the use of textile
products outside their traditional fields of applications, for example, in the construction, medical, automobile, environmental and safety technology sectors. Consequently, nanotextiles could become ubiquitous inindustrial and consumer products in future. Another ubiquitous field of application for ENM is façade coatings.The environment and human health could be affected by unintended release of ENM from these products. The product life cycle and the product design determine the various environmental and health exposure
situations. For example, ENM unintentionally released from geotextiles will probably end up in soils, whereas ENM unintentionally released from T-shirts may come into direct contact with humans and end up in
wastewater. In this paper we have assessed the state of the art of ENM effects on the environment and human health on the basis of selected environmental and nanotoxicological studies and on our own environmental
exposure modeling studies. Here, we focused on ENM that are already applied or may be applied in future to textile products and façade coatings. These ENM's are mainly nanosilver (nano-Ag), nano titanium dioxide (nano-TiO2), nano silica (nano-SiO2), nano zinc oxide (nano-ZnO), nano alumina (nano-Al2O3), layered silica (e.g. montmorillonite, Al2[(OH)2/Si4O10]·nH2O), carbon black, and carbon nanotubes (CNT). Knowing full well that innovators have to take decisions today, we have presented some criteria that should be useful in systematically analyzing and interpreting the state of the art on the effects of ENM. For the environment we established the following criteria: (1) the indication for hazardous effects, (2) dissolution in water increases/decreases toxic effects, (3) tendency for agglomeration or sedimentation, (4) fate during waste water
treatment, and (5) stability during incineration. For human health the following criteria were defined:(1) acute toxicity, (2) chronic toxicity, (3) impairment of DNA, (4) crossing and damaging of tissue barriers, (5) brain damage and translocation and effects of ENM in the (6) skin, (7) gastrointestinal or (8) respiratory tract. Interestingly, some ENM might affect the environment less severely than they might affect human health, whereas the case for others is vice versa. This is especially true for CNT. The assessment of the environmental risks is highly dependent on the respective product life cycles and on the amounts of ENM produced globally.

Policy theme(s)

Chemicals>>Pollutants/hazardous substances>>Nanomaterials
Risk assessment>>Risk assessment methodologies

Keywords

Environment, Health, Nanomaterials, Life cycle, Nanotextiles, Façade coatings

Entry Source:

N/A

Referred to in EC doc:

Selected for Science for Environment Policy News Alert

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http://www.sciencedirect.com/science/article/pii/S0160412011000444
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claudia.som@empa.ch

Title

Stability, Bioavailability, and Bacterial Toxicity of ZnO and Iron-Doped ZnO Nanoparticles in Aquatic Media

Reference

Environ. Sci. Technol., 2011, 45 (2), pp 755–761
DOI: 10.1021/es102266g

Author(s)

Minghua Li, Suman Pokhrel, Xue Jin, Lutz Mdler, Robert Damoiseaux, and Eric M. V. Hoek

Study type

Peer Review Journal

Abstract

The stability and bioavailability of nanoparticles is governed by the interfacial properties that nanoparticles acquire when immersed in a particular aquatic media as well as the type of organism or cell under consideration. Herein, high-throughput screening (HTS) was used to elucidate ZnO nanoparticle stability, bioavailability, and antibacterial mechanisms as a function of iron doping level (in the ZnO nanoparticles), aquatic chemistry, and bacterial cell type. ζ-Potential and aggregation state of dispersed ZnO nanoparticles was strongly influenced by iron doping in addition to electrolyte composition and dissolved organic matter; however, bacterial inactivation by ZnO nanoparticles was most significantly influenced by Zn(2+) ions dissolution, cell type, and organic matter. Nanoparticle IC(50) values determined for Bacillus subtilis and Escherichia coli were on the order of 0.3-0.5 and 15-43 mg/L (as Zn(2+)), while the IC(50) for Zn(2+) tolerant Pseudomonas putida was always >500 mg/L. Tannic acid decreased toxicity of ZnO nanoparticles more than humic, fulvic, and alginic acid, because it complexed the most free Zn(2+) ions, thereby reducing their bioavailability. These results underscore the complexities and challenges regulators face in assessing potential environmental impacts of nanotechnology; however, the high-throughput and combinatorial methods employed promise to rapidly expand the knowledge base needed to develop an appropriate risk assessment framework.

Policy theme(s)

Chemicals >> Pollutants/hazardous substances >> Nanomaterials

Keywords

N/A

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://pubs.acs.org/doi/pdfplus/10.1021/es102266g
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emvhoek@ucla.edu

Title

Nano-TiO2 enhances the toxicity of copper in natural water to Daphnia magna

Reference

Environmental Pollution
Volume 159, Issue 3, March 2011, Pages 729-734

Author(s)

Wenhong Fan, Minming Cui, Hong Liu, Chuan Wang, Zhiwei Shi, Cheng Tan and Xiuping Yang

Study type

Peer Review Journal

Abstract

The acute toxicity of engineered nanoparticles (NPs) in aquatic environments at high concentrations has been well-established. This study demonstrates that, at a concentration generally considered to be safe in the environment, nano-TiO2 remarkably enhanced the toxicity of copper to Daphnia magna by increasing the copper bioaccumulation. Specifically, at 2 mg L_1 nano-TiO2, the (LC50) of Cu2þ concentration observed to kill half the population, decreased from 111 mg L_1 to 42 mg L_1. Correspondingly, the level of metallothionein decreased from 135 mg g_1 wet weight to 99 mg g_1 wet weight at a Cu2þ level of 100 mg L_1. The copper was found to be adsorbed onto the nano-TiO2, and ingested and accumulated in the animals, thereby causing toxic injury. The nano-TiO2 may compete for free copper ions with sulfhydryl groups, causing the inhibition of the detoxification by metallothioneins.

Policy theme(s)

Biodiversity >> Threats to biodiversity >> Human impacts
Chemicals >> Pollutants/hazardous substances >> Nanomaterials
Water >> Water and biodiversity

Keywords

Nano-TiO2, Toxicity, Copper, Daphnia magna, Metallothionein

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.sciencedirect.com/science/article/pii/S0269749110005415
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fanwh@buaa.edu.cn