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. 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. As mentioned in the DoW, task 1.5 was entrusted with the development of the NANoREG data platform. The platform, as expansion of point a) in the DoW of T1.5 (see section 1 above) had to allow for:
Background of the task. Due to the rapid expansion of nanotechnology and the increasing range of MNMs under production and development, it is essential that the potential impacts on human and environmental health are addressed at an early phase of the innovation process. The identification of any potential deleterious effects is therefore necessary in order to prevent any potential environmental or human health adverse effects. The linking of physicochemical characteristics of nanoparticle (NP) to their biological behaviour and its functionality is a first step towards achieving this goal. It is widely accepted that much work is still needed to advance knowledge in the area of physicochemical characterisation of nanomaterials, and how characteristics and properties of these nanomaterials influence their fate and behaviour in the environment and their potential to induce toxicity in different environmental receptors [1]. Rapid growth in nanotechnology is increasing the likelihood of MNMs coming into contact with humans and the environment. Nanoparticles interacting with proteins, membranes, cells, DNA and organelles establish a series of nanoparticle/biological interfaces that depend on colloidal forces as well as dynamic biophysicochemical interactions. These interactions lead to the formation of protein coronas, particle wrapping, intracellular uptake and biocatalytic processes that could have biocompatible or bioadverse outcomes. For their part, the biomolecules may induce phase transformations, free energy releases, restructuring and dissolution at the nanomaterial surface. Probing these various interfaces allows the development of predictive relationships between structure and activity that are determined by nanomaterial properties such as size, shape, surface chemistry, roughness and surface coatings. This knowledge is important from the perspective of safe use of nanomaterials [2]. The generation of a prescribed list of requirements should recognise the limitations of resources and capabilities, but it should also be mindful of achieving scientific robustness in the context of the objectives of a particular study. Main aim and main activities: The main goals of Task 6.3/D6.6 are:
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. 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. In the last years, there has been an emphasis on the experimental testing of nanomaterials using in vitro and in vivo approaches. However, several essential questions on nanomaterial toxicology cannot yet be clarified by such approaches. One of these questions is a putative carcinogenicity of nanomaterials. Due to reasons of feasibility it is not possible to test each single nanomaterial for carcinogenicity. Grouping approaches for safety testing can be chosen in case a common mode of action is known. A relevant group of nanomaterials are likely to share a common mode of carcinogenic action. These nanomaterials belong to a group of materials named poorly soluble, low toxicity particles (PSLT) (Xxxxxxxx et al. 2007), poorly soluble particles of low cytotoxicity (PSP) (Oberdorster 2002) or respirable granular biodurable particles without known significant specific toxicity (GBP) (Roller and Pott 2006). All terms describe the same type of materials. Industrial-relevant nanomaterials like carbon black or titanium dioxide belong to this group. There is a current scientific controversy, whether the lung tumours detected in chronic rat inhalation studies induced by PSLT only appear at high exposure concentrations (i.e. so-called dust ‘overloading’ of the lungs) associated with inflammation. According to the overload hypothesis, in lower (and real-life) exposure levels there is no dust overloading and no inflammation in the lung and consequentially no tumour risk in case an exposure threshold is not exceeded. Several authors (e.g. (Xxxxxx 1992) describe that dust overloading in the rat becomes evident in respirable dust concentrations higher than 1 mg/m³ in a chronic study. Further up to now unclarified aspects with respect to putative health hazards of nanomaterials will be studied. This comprises the systemic distribution of particles after chronic inhalation exposure and a putative accumulation in tissues like brain or the cardiovascular system and putative adverse effects associated with this chronic accumulation. Long-term exposure to biopersistent, poorly soluble nanomaterials and possible carcinogenicity induced thereof, has been identified as one of the major data gaps for regulatory decision process in the field of nanomaterials (Xxxxxx et al. 2011). While an increasing number of short-term data becomes available, long- term inhalation studies according to GLP and OECD TG guidelines in rodents are technically demanding and the resources needed require a h...
Background of the task. Much of the interest in the hazard of high aspect ratio nanomaterials (XXXX) stems from occupational and public health problems caused by inhalation of fibers, especially asbestos. One of the major challenges in nanotoxicology is to be able to predict human risk following long term exposure to low exposure levels based on short term studies in animal models using much higher exposure levels. In addition, the internationally recognized and harmonized protocols for toxicity testing favor rats as model, whereas mice are the preferred animal model in more mechanistic studies involving transgenic animals or –omics methods. MWCNT differ vastly in physico-chemical properties including length, thickness, levels and types of metal impurities, types and levels of surface modifications. To be able to assess the effect of these variations in physicochemical properties, several different CNTs with well-characterized physico-chemical properties should be assessed in the standardized subchronic inhalation test involving several dose levels and time points as well as careful determination of the dosimetry. These sub-chronic inhalation studies are expensive and time consuming and there are presently only two such studies with CNTs available in the scientific literature. However, identification of the physico-chemical properties that drive different toxic effects may also contribute to grouping and ranking of nanomaterials including XXXX by enabling ranking of other CNTs relative to the CNTs used in the sub-chronic inhalation studies.
Background of the task. Task 1.3 implements the link between the scientific WPs 2-6 and WP1. It helps to identify the crucial aspects of the regulation of nanomaterials that NANoREG needs to address (better) and fuels the dialogue between WP1 and the other WPs, helping to oversee how NANoREG actually works on (partially) answering the questions of regulatory relevance (D1.1). Information generated in T1.6 during the implementation of the safety in the value chain case studies (SVCCSs) shall be taken into account. The output of T1.3 feeds directly into the development of the NANoREG framework for the safety assessment of nanomaterials (D1.10 of T1.4) and the related NANoREG Toolbox (D1.12 of T1.7).
Background of the task. Task 1.6 Working Groups (addressing Value Chain Case Studies and other R&D related activities) aim to provide case-specific information on how a nanomaterial is used along a given value chain. Furthermore, by employing expertise from within the NANoREG project, data is produced that show the fate and behaviour of the specific nanomaterial at given stages of the relevant value chain. The fate and behaviour data is especially important for assessing whether release of a nanomaterial can occur and, if so, for whom the release is important (i.e. whether occupational exposure, exposure to consumers or to the environment can take place). Based on the specific results, the T1.6 identifies if there are critical knowledge gaps regarding safety assessments that need to be covered, and by which means. Knowledge generated in T1.6 can feed into tasks 1.3, 1.4, and 1.7. Case studies have been proposed that are deemed relevant for generating knowledge about the SVCCS procedure and for safety aspects related to certain nano-enabled products. A detailed background of VCSS, SVCCS for nanomaterials, and risk assessment associated with value chains and nanomaterials was provided in deliverable D1.6. Deliverable D1.8 provides overall conclusions regarding the outcomes of NANoREG SVCCSs and how they can provide answers to the regulatory questions that were defined as part of T1.1.
