Background of the task. TiO2 in its anatase form as well as in anatase-rutile mixtures was found to induce DNA-damage in several cell types as e.g. keratinocytes or colon epithelial cells in vitro. At the same time, in vivo assays have generated almost no genotoxic effects. Beside inflammation-mediated secondary genotoxicity, generation of oxidative stress is currently discussed as a mechanism of potential genotoxic effects of TiO2. For chemicals in general, cellular distribution and internalization is considered a major factor for genotoxicity. As the intestinal epithelium represents a major barrier for TiO2 following ingestion, we investigated internalization of TiO2 by Caco2 intestinal cells employing time-of-flight secondary ion mass spectrometry (ToF-XXXX). It is important to evaluate in which cell compartments the NPs are detected as well as in which form they are encountered as these parameters may have an impact on the behaviour of the NPs over time and the effects expected at the cellular level. This task may interlink with other tasks such as WP5.3, WP5.5 and WP5.6 as results on Caco2 cells with TiO2 are expected within these tasks.
Background of the task. A relevant and currently not clarified question is a putative carcinogenicity of nanomaterials. Due to reasons of feasibility, it will not be possible to test each single nanomaterial for this effect. Grouping approaches for safety testing can be chosen in case a common mode of action is known. A relevant group of nanomaterials are assumed to share a common mode of toxic action. These nanomaterials belong to a group of materials that can be described as poorly soluble, respirable granular biodurable particles without known significant specific toxicity (GBP). Prominent high production volume nanomaterials like carbon black or titanium dioxide belong to this group. Carbon black and nanosized titanium dioxide have been tested for chronic inhalation carcinogenicity in the rat, further respective data on other GBP nanomaterials are not available. Due to current knowledge, the induction of inflammation after inhalation and lung carcinogenicity appear to be the prominent health hazards for these materials. Up to now, there is no convincing evidence that further health hazards or oral/dermal exposure are relevant. There is a current scientific controversy, whether the lung tumours detected in the chronic rat inhalation studies induced by carbon black and nanosized titanium dioxide only appeared in artificially high exposure concentrations (i.e. so-called dust ‘overloading’ of the lungs) associated with inflammation. The planned study aims at verifying this hypothesis. The aim is to prove whether a dose-response curve with or without a threshold must be assumed for lung tumour induction. For this purpose, an inhalation carcinogenicity study with an extended protocol to enhance tumour detection sensitivity will be performed. Task 4.1 of the NANoREG project is a long-term inhalation study aiming to address this question. A 28-d inhalation study with cerium dioxide had been performed as
Background of the task. ECHA (The European Chemicals Agency) is currently developing guidance documents and appendixes to facilitate registration and risk assessment of manufactured nanomaterials (MNM) under REACH and CLP. This report consequently adhere to the recommended regulatory definition of a nanomaterial proposed by the EC (2011/696/EU) (Xxxxxxxx 2011) and adopted by ECHA for implementation in REACH. In line with the purpose of the REACH regulation, ECHA considers only manufactured nanomaterials and not incidental and natural nanomaterials, which are also covered by the EC recommendation for definition of nanomaterial. To structure the registration of material and chemical substances, REACH provides a number of guidance documents, annexes, appendixes to guide the registrants on required end-points to be reported and recommended methods for data generation. The Guidance consists of two major parts: Concise guidance (Part A to F) and supporting reference guidance (Chapters R.2 to R.20) and are linked as illustrated below in Figure 1.
Background of the task. The VSSA concept was introduced to characterize the size of a monodispersed distribution of spherical, non-porous particles. Such an ideal model simply uses the ratio surface/volume of the particle, which is easily understandable when all the particles are spherical and have the same size. However, in reality, the nanoparticles have a high tendency to aggregate or agglomerate, and the hence the VSSA should consider the reality of the nanomaterials. In practice, it is important to assess how the VSSA concept can be applied to polydisperse distributions of non-spherical particles. A theoretical approach was developed to determine the role of particle shape and polydispersity on the VSSA concept and a model to calculate VSSA for polydisperse non-spherical particles was proposed. To avoid confusion, the VSSA obtained by this model is called total VSSA. These calculated values will then be compared to the measured ones. The most feasible approach to determine the VSSA is by combining the BET surface area and the skeletal density of the powder. The BET surface area analysis normally, include both the external and internal surface (porosity) of the particles while the VSSA concept for identification of an MN may be linked to the external dimensions of the particles. If the particles have an internal porosity (i.e., the porosity from micropores, micro channels, cracks in particles,.., etc.), the BET surface area will be larger than the external surface area and will result in an identification of false positive nano-materials. It means that numerous powders can potentially be falsely identified to consist of MN. A methodology to complete characterisation of powders by in-depth analysis of nitrogen adsorption isotherms was demonstrated to enable the discriminate between the external and internal surface areas in powders. The method is readily applicable to the dry powders without any treatment. For the solid suspended in liquid like colloids, the suspension could potentially be gently dried to collect the solid part. The objective of this study is to determine the applicability and reliability of the VSSA approach to distinguish between nano- and non-nano-materials without necessarily using the number particle size distribution. The work was carried out in the following stages: As a first step, a theoretical study of the effect of particle shape and particle size distribution on the VSSA values and thresholds has been carried out and a model to calculate the VSSA...
Background of the task. In a 2 year inhalation study, conducted according to OECD TG 453, CeO2 nanoparticles (NM-212, Ø 28 nm) were used as a representative of poorly soluble, respirable granular biodurable particles without known significant specific toxicity (GBP). The objective was to investigate potential low dose effects caused by chronic inhalation and also to compare the particle distribution in lung tissue by the use of imaging techniques. In order to correlate particle distribution with potential effects of CeO2 nanoparticles, slices for ToF-XXXX and IBM studies are being taken adjacent to those for histopathological investigations.
Background of the task. The innovative and economic potential of MNMs is threatened by a limited understanding of the related EHS (Environmental Health and Safety) issues. While toxicity data is continuously becoming available, the relevance to regulators is often unclear or unproven. The shrinking time to market of new MNMs drives the need for urgent action by regulators. NANoREG is the first FP7 project to deliver the answers needed by regulators and legislators on EHS by linking them to a scientific evaluation of data and test methods. As previously highlighted in Section I, regulatory questions 11, 12 and 13 defined at the start of the NANoREG project are associated with WP3: The work on Task 3.4 has contributed to answer questions 11 and 12, and in some extent also provided input into addressing Q13. State of the art tools for qualitative and semi-quantitative assessment of release/exposure were reviewed (ART, Stoffenamanager-Nano). These tools are currently being used by the nanosafety community; however, they have not been evaluated or demonstrated and therefore their applicability and appropriateness for regulatory purposes is hampered and unknown. The task has gone beyond the state of the art by developing and demonstrating a two-box quantitative model for exposure assessment of NMs and implementing this into a web-based tool.
Background of the task. TEM analyses can play an important role in the implementation of the newly established regulatory framework of the European Commission (EC) regulating the use of nanomaterials in consumer products [2-8]. TEM is one of the few techniques that can identify nanoparticles according to the current definitions. If particles can be brought on an electron microscopy (EM) grid and if their distribution is homogeneous and representative for the sample, the combination of transmission electron microscopy (TEM) imaging with image analysis is one of the few methods that allow obtaining number-based distributions of the particle size and shape, describing the sample quantitatively [9-11]. EM further is a well suited technique because of its resolution covering the size range from 1 nm to 100 nm specified in various definitions of NM [12], and its ability to visualize colloidal nanomaterials as well as primary particles in aggregates in two dimensions. Disadvantages of EM analysis of nanomaterials include the bias from suboptimal sampling and sample preparation, the estimation of properties of 3D objects from 2D projections, the interpretation of the size of primary particles in aggregates or agglomerates, the relatively high number of particles required for measurement, and the need to develop algorithms for automated image analysis for each separate type of nanomaterial. In many cases, technical solutions that can overcome these disadvantages are available or under development, e.g. more advanced EM techniques such as electron tomography and cryo-EM can be used to obtain information about the 3rd dimension of the particles and to avoid artefacts [13-17]. A review discussing the different steps required for the physical characterization of nanomaterials in dispersion by transmission electron microscopy in a regulatory framework is given by Xxxx et al. [18]. The implementation of the EC-definition of a nanomaterial [4] across various regulatory fields requires a detailed detection and characterization of manufactured nanomaterials by appropriate, validated testing methods [19, 20]. In this deliverable, SOPs for quantitative TEM analysis in the context of the EC definition are proposed and applied and validated on a series of nanomaterials, by intra-laboratory and inter-laboratory validation based on the estimation of the measurement uncertainties and by interpretation of the obtained results with alternative methods. These include ensemble techniques based on light scatt...
Background of the task. This document is intended to provide an evaluation of expert opinion regarding foresight into the impact on risk management of trends in a) nanomaterial uses and b) risk analysis applied to reasonably anticipated future nanomaterial uses. The document is intended to serve as input to the ProSafe White Paper, and generally as a tool for risk managers considering priorities for policy and methods development. An underlying reason for the foresight report is concern that nano-enabled products may enter markets faster than the development of risk management capabilities suitable for them. Therefore, so that risk uncertainty does not impede innovation, regulators will need to understand the likelihoods for specific kinds of nanomaterial use in products as well as likelihoods that there will be methods to manage risks of those products arising from the added nanomaterials. Focus on Safe by Design SbD methods is particularly useful in this context of use of an emerging set of technologies (nanotechnologies).
Background of the task. The relevance of the task resides in the assessment of possible toxic effects of nanoparticles in two potentially susceptible populations: pregnant women and their in utero conceptuses. The relevance of the developed data for the NANoREG project is that different levels of exposure might be developed by regulators for pregnant women in comparison to those released for the general population of workers and consumers. Both cerium oxide and carbon nanotubes represent material to which people, including pregnant women, may come in contact to, both in environmental and occupational settings. These nanomaterials are in fact included in the OECD list of nanomaterials having high relevance in occupational setting (OECD. Working Party on Manufactured Nanomaterials, 2008) and in the list of environmental relevant nanomaterials released by RIVM (RIVM Report, 2009). The main route through which people may come in contact is through inhalation; however a substantial fraction of nanomaterials are cleared from the respiratory tract via the mucociliary escalator, and are subsequently ingested into the gastrointestinal tract. The unintentional hand to mouth transfer is a second mechanism through which nanomaterials may reach the gastrointestinal tract. In the light of the reported systemic effects of CNTs associated with In vivo crossing of the gastro-intestinal barrier after oral ingestion (Xxxxxxxx, 2009) we selected a biopersistent material such as CNTs for exploring possible adverse cumulative effects related to oral ingestion during the gestation period in our experimental model of pregnant rodents. As far as cerium oxide is concerned, this is a puzzling nanomaterial, for which both pro-oxidant (damaging) and anti-oxidant (protective) effects have been reported (reviewed in Pietroiusti, 2012). Among others, host susceptibility may be a factor influencing these different outcomes. Since no data on health effects of nanoceria after pulmonary exposure in pregnant animals are currently available, we have chosen to evaluate its possible toxicity in this potentially highly susceptible population.
Background of the task. The information in the relational database that contains information on nanomaterial’s physicochemical characteristics and (eco)toxicity can be used to identify physicochemical properties related to the fate and toxicity of nanomaterials, to develop structure-activity relationship (SAR) models, to derive grouping principles and to contribute to the development of a Safe by Design strategy (deliverable 6.6 of the NANoREG project) by defining a “safe window” of (eco)toxicological parameters. The database is designed to store information on both the properties of pristine nanomaterials (e.g. particle’s composition) as well as their interaction with biological and environmental components; this is done to keep track consistently of the particle’s history and identify the influence of biological and environmental conditions on nanomaterial’s toxicity (e.g. the effect of the biomolecular corona on the cellular uptake and toxicity of nanoparticles). The relational database is filled with information retrieved from peer reviewed scientific literature and for the purpose of data entry, a software tool has been developed within the NANoREG project, to enable the data entry process in a consistent manner. The database includes 3 types of data on nanomaterial characteristics and toxicity:
