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Vogel U.,Danish Nanosafety Center | Savolainen K.,Finnish Institute of Occupational Health | Wu Q.,DNV GL | Van Tongeren M.,Institute of Occupational Medicine IOM | And 2 more authors.
Handbook of Nanosafety: Measurement, Exposure and Toxicology | Year: 2014

Handbook of Nanosafety: Measurement, Exposure and Toxicology, written by leading international experts in nanosafety, provides a comprehensive understanding of engineered nanomaterials (ENM), current international nanosafety regulation, and how ENM can be safely handled in the workplace. Increasingly, the importance of safety needs to be considered when promoting the use of novel technologies like ENM. With its use of case studies and exposure scenarios, Handbook of Nanosafety demonstrates techniques to assess exposure and risks and how these assessments can be applied to improve workers safety. Topics covered include the effects of ENM on human health, characterization of ENM, aerosol dynamics and measurement, exposure and risk assessment, and safe handling of ENM. Based on outcomes from the NANODEVICE initiative, this is an essential resource for those who need to apply current nanotoxicological thinking in the workplace and anyone who advises on nanosafety, such as professionals in toxicology, occupational safety and risk assessment. © 2014 Elsevier Inc. All rights reserved. Source

Hansen S.F.,Technical University of Denmark | Jensen K.A.,Danish Nanosafety Center | Baun A.,Technical University of Denmark
Journal of Nanoparticle Research | Year: 2014

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. © 2013 Springer Science+Business Media Dordrecht. Source

Norgaard A.W.,Danish Nanosafety Center | Hansen J.S.,Danish Nanosafety Center | Sorli J.B.,Danish Nanosafety Center | Levin M.,Danish Nanosafety Center | And 4 more authors.
Toxicological Sciences | Year: 2014

A number of cases of pulmonary injury by use of aerosolized surface coating products have been reported worldwide. The aerosol from a commercial alcohol-based nanofilm product (NFP) for coating of nonabsorbing surfaces was found to induce severe lung damage in a recent mouse bioassay. The NFP contained a 1H,1H,2H,2H-perfluorooctyl trialkoxysilane (POTS) and the effects were associated with the hydrolyzed forms of the silane; increase in hydrolyzation resulted in faster induction of compromised breathing and induction of lung damage. In this study, the impact of the solvent on the toxicity of POTS has been investigated. BALB/cA mice were exposed to aerosolized water-based NFPs containing POTS, and solutions of hydrolyzed POTS in methanol, ethanol, and 2-propanol, respectively. No acute respiratory effect was observed at exposure concentrations up to 110 mg/ m3 with an aqueous solution of POTS. However, exposure to POTS in methanol resulted in a decrease of the tidal volume-an effect that did not resolve within the recovery period. After 27 min of exposure, the tidal volume had decreased by 25%, indicating partial alveolar collapse. For POTS in ethanol and 2-propanol, a 25% reduction of the tidal volume was observed after 13 and 9 min, respectively; thus, the tidal volume was affected by increase of the chain length. This was confirmed in vitro by investigating lung surfactant function after addition of POTS in different solvents. The addition of vaporized methanol, 2-propanol, or acetone to aerosolized POTS in methanol further exacerbated the tidal volume reduction, demonstrating that the concentration of vaporized solvent participated in the toxicity of POTS. © the author 2013. Source

Levin M.,Technical University of Denmark | Levin M.,Danish Nanosafety Center | Gudmundsson A.,Lund University | Pagels J.H.,Lund University | And 5 more authors.
Aerosol Science and Technology | Year: 2015

A comparison between three different types of particle sizing instruments (fast mobility particle sizer, FMPS; electrical low pressure impactor, ELPI; and scanning mobility particle sizer, SMPS) and one condensation particle counter (CPC) was made to compare instrument response in terms of size distributions and number concentration. Spherical oil droplets in 39 different sizes, with geometric mean diameter (GMD) ranging from 50 nm to 820 nm, were used as test particles. Furthermore, a characterization of the FMPS unipolar charger behavior was made to analyze the measured size distributions and number concentrations. The results show that all three sizing-instruments agree well for particle sizes below 200 nm, both in terms of size and number concentration, but the FMPS deviates clearly when particle sizes exceed 200 nm. Above this, the FMPS underestimates the particle size throughout the remainder of the size range, with an apparent upper limit for GMD of 300 nm. It also estimates a higher particle number concentration as compared to the other instruments. Analysis of the 22 FMPS electrometer currents and calculation of average number of charges per particle show a diameter dependence of response of for the FMPS unipolar charger. The resulting calculated electrical mobility showed a minimum in mobility for spherical particles at 577 nm, which indicates an interfering range of particles above the measurement range, but below the cut-off of the inlet pre-separator (1 m). The study concludes that particle distributions with a true GMD above 200 nm cannot be measured reliably with the FMPS. © 2015 American Association for Aerosol Research. Source

Levin M.,Technical University of Denmark | Levin M.,Danish Nanosafety Center | Koponen I.K.,Danish Nanosafety Center | Jensen K.A.,Danish Nanosafety Center
Journal of Occupational and Environmental Hygiene | Year: 2014

In this study, we show the different dustiness characteristics of four molecular pharmaceutical powder candidates and evaluate the performance of HEPA filters damaged with three different pinhole sizes and exposed to dust using real industrial powders in a miniaturized EN15051 rotating drum dustiness tester. We then demonstrate the potential use of such data using first-order exposure modeling to assess the potential worker exposure and transmission of active powder ingredients into ventilation systems. The four powders had highly variable inhalable dustiness indices (1,036 - 14,501 mg/kg). Dust particle size-distributions were characterized by three peaks; the first occurred around 60-80 nm, the second around 250 nm, and the third at 2-3 μm. The second and third peaks are often observed in dustiness test studies, but peaks in the 60-80 nm range have not been previously reported. Exposure modeling in a 5 times 20 kg powder pouring scenario, suggests that excessive dust concentrations may be reached during use of powders with the highest dustiness levels. By number, filter-damage by three pinhole sizes resulted in damage-dependent penetration of 70-80 nm-size particles, but by volume and mass the penetration is still dominated by particles larger than 100 nm. Whereas the exposure potential was evident, the potential dust concentrations in air ducts following the pouring scenario above were at pg/m3 levels. Hence, filter penetration at these damage levels was assumed to be only critical, if the active ingredients were associated with high hazard or unique product purity is required. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: An example of a typical particle number time-series of a complete dustiness test. It provides information on the HEPA-filter used including a scanning electron microscopy image of it. It also provides APS-measurements of particles penetrating the damaged HEPA-filter.] © 2014 Copyright Taylor and Francis Group, LLC. Source

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