Risk Assessment Of Nanomaterials Research Articles

Trophic Transfer of Metal Oxide Nanoparticles in the Tomato-Helicoverpa armigera Food Chain: Effects on Phyllosphere Microbiota, Insect Oxidative Stress, and Gut Microbiome.

Understanding the trophic transfer and ecological cascade effects of nanofertilizers and nanopesticides in terrestrial food chains is crucial for assessing their nanotoxicity and environmental risks. Herein, the trophic transfer of La2O3 (nLa2O3) and CuO (nCuO) nanoparticles from tomato leaves to Helicoverpa armigera (Lepidoptera: Noctuidae) caterpillars and their subsequent effects on caterpillar growth and intestinal health were investigated. We found that 50 mg/L foliar nLa2O3 and nCuO were transferred from tomato leaves to H. armigera, with particulate trophic transfer factors of 1.47 and 0.99, respectively. While nCuO exposure reduced larval weight gain more (34.7%) than nLa2O3 (11.3%), owing to higher oxidative stress (e.g., MDA and H2O2) and more serious intestinal pathological damage (i.e., crumpled columnar cell and disintegrated goblet cell) by nCuO. Moreover, nCuO exposure led to a more compact antagonism between the phyllosphere and gut microbiomes compared to nLa2O3. Specifically, nCuO exposure resulted in a greater increase in pathogenic bacteria (e.g., Mycobacterium, Bacillus, and Ralstonia) and a more significant decrease in probiotics (e.g., Streptomyces and Arthrobacter) than nLa2O3, ultimately destroying larval intestinal immunity. Altogether, our findings systematically revealed the cascade effect of metal oxide nanomaterials on higher trophic consumers through alteration in the phyllosphere and insect gut microbiome interaction, thus providing insights into nanotoxicity and environmental risk assessment of nanomaterials applied in agroecosystems.

Proposal for a qualification system for New Approach Methodologies (NAMs) in the food and feed sector: example of implementation for nanomaterial risk assessment

Abstract Plenty of new approach methodologies (NAMs) for risk assessment have been developed but only some are included in OECD Test Guidelines (TGs) for regulatory implementation. Nevertheless, NAMs are increasingly applied, e.g. for nanomaterial (NM) risk assessments. The EFSA Guidance on NM risk assessment suggests that NAM‐derived data concerning degradation/dissolution (in relevant biofluids), intestinal uptake/crossing, genotoxicity, cytotoxicity, oxidative stress, (pro‐)inflammatory potential and barrier integrity, for many of which no OECD TGs exist, have to be evaluated first. Consequently, NM risk assessments involve data from non‐guideline studies, requiring time‐consuming and challenging case‐by‐case evaluations. Establishing an OECD TG is a formal process aiming for international use according to the Mutual Acceptance of Data (MAD). However, not every promising NAM can be prioritised for OECD TGs. A qualification, based on an expert opinion, may enable an efficient use of adequate NAMs for a specific context‐of‐use. Furthermore, it supports the optimisation of promising NAMs for regulatory applications. Existing qualification systems operate in the context of e.g., drug development tools (FDA) and research and development into pharmaceuticals (EMA). The NAMS4NANO consortium was tasked to propose a generic framework for a qualification system for chemical risk assessment in the food and feed sector to speed up the regulatory use of NAMs. Here we describe our proposal including the process and evaluation criteria. A detailed test method description, preferably as standard operating procedures (SOPs), describing the set‐up of the NAM including its application and evaluation phase is crucial. Furthermore, the scientific validity, i.e. its reliability and relevance for the context‐of‐use, needs to be demonstrated, for which we suggest a less rigorous process compared to OECD TGs. We propose to initially establish a qualification system for NM risk assessment, aligned with the EFSA framework. This document is an interim version to stipulate a broader discussion among experts and stakeholders.

Toxic effects of multi-walled carbon nanotubes and ZnO nanoparticle exposure on pathology and apoptosis on the liver of Cyprinus carpio

ZnO nanoparticles (ZnONPs) and carbon nanotubes (CNTs) are frequently used nanoparticles with unique features. Aquatic organisms are exposed to a combination of contaminants in natural water systems, so the combination effect of two or more nanomaterials has caused much concern. In this study, the toxicity to the liver of common carp was explored under four weeks of exposure to single ZnONPs or in combination with multi-walled CNTs (MWCNTs). The results demonstrated that ZnONPs induced pathological changes and apoptosis in the liver. In combination, decreased pathological changes were observed in the LSC-ZnONPs group (50 mg L-1 ZnONPs and 0.25 mg L-1 MWCNTs) at the microscopic level and ultrastructural level, and increased pathological changes in the HSC-ZnONPs group (50 mg L-1 ZnONPs and 2.5 mg L-1 MWCNTs). A 52% reduction in the percentage of TUNEL-positive nuclei in the LSC-ZnONPs group and a 33% increase in the HSC-ZnONPs group were observed compared to the ZnONPs group. The mRNA expression of apoptosis-related genes, including caspase3, BAX, and XBP1, were significantly up-regulated in the exposure groups, confirming the occurrence of apoptosis. Significantly decreased caspase 3 and BAX mRNA levels in the co-exposure groups were detected compared to the ZnONPs group. Nevertheless, the XBP1 mRNA level was significantly upregulated in the LSC-ZnONPs group, but downregulated in the HSC-ZnONPs group, indicating multiple signal pathways involved in the apoptosis. In conclusion, a low concentration of MWCNTs (0.25 mg L-1) decreased the toxic effect of ZnONPs on common carp, but a high concentration of MWCNTs (2.5 mg L-1) enhanced it. This study will contribute to developing future risk assessment and management strategies for nanomaterials.

Next Generation Risk Assessment approaches for advanced nanomaterials: Current status and future perspectives

This manuscript discusses the challenges of applying New Approach Methodologies (NAMs) for safe by design and regulatory risk assessment of advanced nanomaterials (AdNMs). The authors propose a framework for Next Generation Risk Assessment of AdNMs involving NAMs that is aligned to the conventional risk assessment paradigm. This framework is exposure-driven, endpoint-specific, makes best use of pre-existing information, and can be implemented in tiers of increasing specificity and complexity of the adopted NAMs. The tiered structure of the approach, which effectively combines the use of existing data with targeted testing will allow safety to be assessed cost-effectively and as far as possible with even more limited use of vertebrates. The regulatory readiness of state-of-the-art emerging NAMs is assessed in terms of Transparency, Reliability, Accessibility, Applicability, Relevance and Completeness, and their appropriateness for AdNMs is discussed in relation to each step of the risk assessment paradigm along with providing perspectives for future developments in the respective scientific and regulatory areas.

New insight into nanomaterial-mediated dissemination of phage-borne resistance genes: Roles of humic acid and illumination

Bacteriophages are key reservoirs of antibiotic resistance genes (ARGs) and are pivotal for their acquisition, maintenance, and dissemination. As extensively distributed contaminants, nanomaterials can interfere with the horizontal transfer of phage-borne ARGs. However, the effects of environmental factors on this process remain unclear. Therefore, the effect of nanoscale titanium dioxide (nTiO2) on the dissemination of ARGs via bacteriophage transduction under humic acid (HA) and Ultraviolet A illumination was investigated in this study. In the dark, 20 mg/L nTiO2 did not promote the propagation of ARGs and attenuated the positive effect of HA on the transductive transfer of ARGs. Further evidence revealed that nTiO2 can absorb HA on its surface and decrease the free HA content, thereby mitigating the instability of the outer membrane and leading to diminished transductant formation. Conversely, coexposure to HA and nTiO2 synergistically promoted transduction under Ultraviolet A illumination. Massive superoxide radicals produced by photoexcitation of the HA-nTiO2 complex elevated the membrane permeability and boosted intracellular oxidative stress, resulting in the enhanced dissemination of ARGs through phage transduction. The results of this study provide insights into the roles of environmental factors in transductive ARGs dissemination mediated by nTiO2 and are beneficial for the risk assessment of nanomaterials.

Safety and efficacy of a feed additive consisting of natrolite-phonolite obtained from volcanic rock from Kaiserstuhl for all animal species (Hans G. Hauri Mineralstoffwerk GmbH).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of natrolite-phonolite obtained from volcanic rock from Kaiserstuhl as a technological additive (functional group: anticaking) for all animal species. According to the conventional risk assessment, due to the lack of adequate data, the Panel is not in a position to conclude on the safety of the additive for the target species under the proposed conditions of use. However, from the tolerance studies in cattle for fattening and weaned piglets, effects observed in animal performance and blood clinical biochemistry suggest adverse effects on the animals supplemented with the additive. Based on current knowledge, there is no indication of substantial absorption of the components of the additive and, therefore, of concern for the consumer. The FEEDAP Panel is not in the position to conclude on the potential of the additive to be a skin and eye irritant. The additive is considered a respiratory and dermal sensitiser. In the absence of suitable data, the presence of small/nanoparticles cannot be excluded. As no suitable data in line with the requirements of the Guidance on risk assessment of nanomaterials were provided by the applicant, the potential risks associated with the presence of nanoparticles for the target species, the consumer and the user could not be assessed. Due to the lack of sufficient data, the Panel is not in a position to conclude on the efficacy of the additive.

Safety and efficacy of a feed additive consisting of zeolites (≥ 50%) obtained from Neapolitan Yellow Tufa for all animal species (Italiana Zeoliti s.r.l.).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of zeolites (≥ 50%) obtained from Neapolitan Yellow Tufa as a technological additive (functional group: anticaking) for all animal species. The additive is specified to contain not less than 50% of zeolites, namely phillipsite, chabazite and analcime. Neapolitan Yellow Tufa originates from the volcanic activity of Campi Flegrei, Italy. According to the conventional risk assessment, due to a lack of adequate data, the safety of the additive for the target species cannot be established. Based on current knowledge, there is no indication of substantial absorption of the components of the additive and, therefore, of concern for the consumer. The additive poses a risk by inhalation. It is not irritant to the skin. The Panel cannot conclude on the eye irritancy and on the dermal and respiratory sensitisation potential of the additive. As no suitable data in line with the requirements of the Guidance on risk assessment of nanomaterials were provided by the applicant, the potential risks associated with the presence of nanoparticles for the target species, the consumer and the user could not be assessed. The additive is safe for the environment. The additive is considered to be efficacious in feedingstuffs for all animal species at 20,000 mg/kg complete feed.

Size- and Dose-Dependent Body-Wide Organ Transcriptomic Responses to Calcium Phosphate Nanomaterials.

Nanomaterials are widely used in clinical practice. There are potential risks of body-wide infiltration due to their small size; however, the body-wide reliable risk assessment of nanoparticle infiltration is not fully studied and established. In this study, we demonstrated the size- and dose-dependent body-wide organ transcriptomic responses to calcium phosphate nanomaterials in vivo. In a mice model, a calcium phosphate nanocluster (amorphous calcium phosphate, ACP, ∼1 nm in diameter) and its crystallization product (ACP-M, ∼10 nm in diameter) in a series of doses was administrated systematically; multiorgan transcriptomics were then performed with tissues of heart, liver, spleen, lung, kidney, and brain to investigate the systematic effect of dose and size of nanomaterials on the whole body. The results presented gene expression trajectories correlated with the dose of the nanomaterials and tissue-specific risk effects in all detected tissues. For the dose-dependent tissue-specific risk effects, lung tissue exhibited the most significant risk signatures related to apoptosis, cell proliferation, and cell stress. The spleen showed the second most significant risk signatures associated with immune response and DNA damage. For the size-dependent tissue-specific risk effects, ACP nanomaterials could increase most of the tissue-specific risk effects of nanomaterials in multiple organs than larger calcium phosphate nanoparticles. Finally, we used the size- and dose-dependent body-wide organ transcriptomic responses/risks to nanomaterials as the standards and built up a risk prediction model to evaluate the risk of the local nanomaterials delivery. Thus, our findings could provide a size- and dose- dependent risk assessment scale of nanoparticles in the transcriptomic level. It could be useful for risk assessment of nanomaterials in the future.

SciRAPnano: a pragmatic and harmonized approach for quality evaluation of in vitro toxicity data to support risk assessment of nanomaterials.

Large amounts of nanotoxicity data from alternative non-animal (in vitro) test methods have been generated, but there is a lack of harmonized quality evaluation approaches for these types of data. Tools for scientifically sound and structured evaluation of the reliability and relevance of in vitro toxicity data to effectively inform regulatory hazard assessment of nanomaterials (NMs), are needed. Here, we present the development of a pragmatic approach to facilitate such evaluation. The tool was developed based on the Science in Risk Assessment and Policy (SciRAP) tool currently applicable to quality evaluation of chemical toxicity studies. The approach taken to develop the tool, referred to as SciRAPnano, included refinement of the original SciRAP in vitro tool through implementation of identified NM-relevant criteria, and further refined based on a set of case studies involving evaluation of 11 studies investigating in vitro toxicity of nano-sized titanium dioxide. Parameters considered cover key physicochemical properties as well as assay-specific aspects that impact NM toxicity, including NM interference with test methods and NM transformation. The final SciRAPnano tool contains 38 criteria for reporting quality, 19 criteria for methodological quality, and 4 guidance items to evaluate relevance. The approach covers essential parameters for pragmatic and harmonized evaluation of NM in vitro toxicity studies and allows for structured use of in vitro data in regulatory hazard assessment of NMs, including transparency on data quality.

Effect of carbon nanomaterials on functional diversity and structure of soil microbial community under single and repeated exposures.

The extensive application of carbon nanomaterials (CNMs) has attracted increasing studies concerned about its environmental impact. These studies focus on single exposure to CNMs, but repeated exposures with relatively low concentration are more likely to occur under actual exposure scenario. In this study, we studied the metabolic functional and structure of soil microorganism community under single and repeated exposures to multiwalled carbon nanotubes (MW), graphene (GR), and fullerene (C60) by Biolog EcoPlates and high-throughput sequencing. Our findings revealed that repeated exposures to CNMs significantly increase the metabolic activity and diversity of the soil microbial community as compared with single exposure. Principal component and similarity analysis not only indicated that GR exerted a stronger effect on soil microbial diversity among three exposures compared to C60 and MW, but also revealed that the metabolic activity of the soil microbial community was more affected by the exposure scenarios of CNMs than the type of CNMs. These findings elucidated the effect of CNMs under different exposure scenarios on soil microorganism community, providing a new perspective on the risk assessment of nanomaterials.

Ecotoxicity Analysis and Risk Assessment of Nanomaterials for the Environmental Remediation

AbstractThe evolution of a safe‐by‐design work premised on nanotechnology relies on the regulation of healthcare, safety, and environmental concerns throughout the manufacture, handling, preservation, assimilation, and disposal of nanomaterials. The practically infinite potential for nanoparticles to be functionalized, chemically interacted with, and added to new products necessitates a new management method for the safe and hazard‐free application of nanotechnology. Nanomaterials (NMs) like silver NMs and nanomaterial composites have a limited quantity of accurate toxicity and ecotoxicological evidence, which has a severe effect on the ecosystem. Due to the intricate and cross‐disciplinary architecture for several components and processes at the nanoscale, risk assessment in the field of nanotechnology necessitates an integrated interdisciplinary approach. In this review, the study begins by providing an insight into the general characteristics of nanoparticle synthesis and ecotoxicity assessments using a variety of green solutions. In addition, there are sections on safety protocols that encourage industrialists to use NMs more effectively in their operations.

Agglomeration Behavior and Fate of Food-Grade Titanium Dioxide in Human Gastrointestinal Digestion and in the Lysosomal Environment.

In the present study, we addressed the knowledge gaps regarding the agglomeration behavior and fate of food-grade titanium dioxide (E 171) in human gastrointestinal digestion (GID). After thorough multi-technique physicochemical characterization including TEM, single-particle ICP-MS (spICP-MS), CLS, VSSA determination and ELS, the GI fate of E 171 was studied by applying the in vitro GID approach established for the regulatory risk assessment of nanomaterials in Europe, using a standardized international protocol. GI fate was investigated in fasted conditions, relevant to E 171 use in food supplements and medicines, and in fed conditions, with both a model food and E 171-containing food samples. TiO2 constituent particles were resistant to GI dissolution, and thus, their stability in lysosomal fluid was investigated. The biopersistence of the material in lysosomal fluid highlighted its potential for bioaccumulation. For characterizing the agglomeration degree in the small intestinal phase, spICP-MS represented an ideal analytical tool to overcome the limitations of earlier studies. We demonstrated that, after simulated GID, in the small intestine, E 171 (at concentrations reflecting human exposure) is present with a dispersion degree similar to that obtained when dispersing the material in water by means of high-energy sonication (i.e., ≥70% of particles <250 nm).

Decision support for selection of new materials considering socio-economic and broader environmental aspects

A growing awareness of the inclusion of aspects that go beyond direct environmental and health risks has characterized the evaluation of new technologies in recent years. Broader environmental and socio-economic aspects are now seen as relevant factors for the sustainable success of corresponding products. As a contribution to the realization of this mindful perspective, in a collaborative project on risk governance in nanotechnology (EU Horizon 2020 project NANORIGO), a set of criteria to support decision-making in the selection of materials at early developmental stages has been developed and integrated into a stochastic multicriteria acceptance analysis. The main categories of criteria and an optional set of corresponding weights were selected based on surveys of project partners and stakeholders. The criteria cover both broader environmental and socioeconomic aspects and are differentiated by the life cycle stages of nanomaterials and potential alternative materials. We identified and weighted 24 distinctive criteria for broader environmental aspects and 32 distinctive criteria for socio-economic aspects, with the help of a total of 62 survey participants. In order to address the level of knowledge of both laypersons and experts, the input questionnaire is divided into a tiered structure. Instead of a fully quantitative approach based on native units, semiquantitative scales are used to assess the input information. This structure aims to avoid the knowledge requirements and resources needed for a full life cycle analysis in terms of environmental or socio-economic impacts. To demonstrate its applicability for decision support, we applied the method to two case studies. Partners of the project tested our survey on cases like carbon nanofibers in car parts and nanomaterials in tire rubbers. The used method makes it possible to deal with uncertainty and ignorance in the early stages of development and still compute a comparison of the given alternatives. In this way, it can be combined with existing tools for risk assessment of (nano)materials to achieve a comprehensive prospective characterization of potential material options at an early stage of the innovation process.

59 First-in-Human Controlled Exposure to Inhaled Graphene Oxide

Abstract Graphene oxide nanomaterials have been developed for wide-ranging applications, but has potential safety concerns for human health. Controlled inhalation exposures in human volunteers have been a vital means to determine the effects and mechanisms of ultrafine particles in air pollution, however, few studies have used this approach to explore the effects of nanomaterials. We conducted a double-blind randomised controlled study to determine whether inhalation of graphene oxide affects pulmonary or cardiovascular function. A high purity graphene oxide was synthesised with a thickness of 1-2 layers in two sizes: ‘small’ (lateral dimensions: 100-1700 nm) and ‘ultrasmall’ (30-500 nm). Graphene oxide particles at 200 µg/m3, or filtered air, were inhaled for 2 hours by 14 young healthy volunteers on repeated visits, with measurement of cardiorespiratory parameters before and across 4 hours after exposure. Graphene oxide exposure was well-tolerated with no adverse effects. Heart rate, blood pressure, lung function and inflammatory markers were unaffected by graphene oxide irrespective of particle size. GO did not change blood biomarkers of coagulation, however, there was a mild increase in thrombus formation in an ex vivo model of arterial injury. Proteomics revealed very few differential plasma proteins. Overall, acute inhalation of graphene oxide was not associated with overt detrimental effects in healthy humans. These findings demonstrate the feasibility of carefully controlled human exposures for risk assessment of graphene nanomaterials.

4 An Introduction to the Sunshine Project Investigating the Risk Assessment of Multicomponent Nanomaterials.

Abstract Multicomponent nanomaterials (MCNM), sometimes called nanohybrids, are advanced materials receiving increased interest in their novel or enhanced properties. Research into MCNM is in its infancy meaning that little is known about their hazard, risk or whether there is regulatory preparedness for their increased use. SUNSHINE is an industry-oriented project, where leading research and technology organisations will cooperate with SMEs and large industries to develop and implement simple, robust, and cost-effective Safe and Sustainable by Design (SSbD) strategies for materials and products incorporating advanced multi-component nanomaterials. This presentation will introduce the key elements in the project including investigations into whether existing characterisation and toxicology testing protocols are applicable and whether existing regulatory frameworks are fit for purpose for these complex structures. It will also introduce how MCNM are being used as a case study for the use of the Safe and Sustainable by Design framework. SUNSHINE project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 952924.

Occupational exposure to nanomaterials: A bibliometric study of publications over the last decade.

Owing to the increased use of nanomaterials, the number of employees and professionals who are exposed to these chemicals is on the rise, despite the paucity of organized data on the possible dangers associated with exposure to these compounds. Multiple studies reveal that the lack of nanosafety awareness among employees and businesses is a serious problem that must be addressed. This shortage of information may result from insufficient knowledge generation or transmission. Academic publications play a significant role in producing new knowledge. This study presents a comprehensive bibliometric analysis of published research on workplace nanosafety which this bibliometric analysis aims to establish the permeability and significance of nanosafety themes from an occupational safety and health viewpoint in academia, to gain a better understanding of the knowledge generation phase in the area, and detected advantages and disadvantages of the topic. Scopus was used as the data source in this study. A total of 1170 publications were gathered and analyzed. The results indicated that the United States is a leader in several aspects of nanosafety at the workplace. The synthesis of co-citation and author-keyword phrases provided insight into determining the focal points of the current study. Analysis of meta data indicates that the number of writers is rising. Nanomaterial toxicity, risk assessment, and occupational exposure are the three hottest topics in this field, according to the result. In addition, the findings included worldwide growth rate, collaborative research fields, keywords, journals, and funding agencies. The advantages and disadvantages of the knowledge creation phase of nanosafety at the workplace were examined in the conclusion.

Natural Bioactive Phytocompounds to Reduce Toxicity in Common Carp Cyprinus carpio: A Challenge to Environmental Risk Assessment of Nanomaterials

Nanomaterials, due to their large aspect-to-size ratio and reactive surfaces that facilitate their access through biological barriers, can induce oxidative stress in host cells. Therefore, there is a growing concern about the biological risks of nanomaterials. This study investigated the biological effects of copper (1.5 mg/L) as CuO or nanoparticles (Cu-NPs) in common carp Cyprinus carpio along with the beneficial effects of Myristiga fragrans seed extract (MFSE) administrated as post-treatment at different doses (4 or 8 or 12 mg/L) for 28 days. The MFSE exhibited a protective role by reducing in a dose-dependent manner the bioaccumulation of Cu level in CuO (from 2.46 to 1.03 µg/Kg in gills; from 2.44 to 1.06 µg/Kg in kidney) and Cu-NPs treated carps (from 2.44 to 1.23 µg/Kg in gills; from 2.47 to 1.09 µg/Kg in kidney) as well as modulating different blood parameters. A mitigation of the histological alterations induced by CuO and Cu-NPs exposure in carp gills (i.e., primary and secondary lamellar degeneration, lamellar fusion, necrosis) and kidneys (i.e., abnormal glomerulus, tubular injury, necrosis) was also observed after MFSE administration. The dietary supplementation of MFSE modulated also the antioxidant defense of carps with respect to the elevated levels of lipid peroxidation (LPO) and glutathione (GST) and the reduced catalase (CAT) induced by CuO and Cu-NPs. Overall, the CuO and Cu-NPs-induced toxicity in C. carpio was mitigated by using MFSE. Further studies are suggested to determine the optimum dose and delivery method of MFSE to guarantee a sustainable conservation of aquatic species.

Towards harmonisation of testing of nanomaterials for EU regulatory requirements on chemical safety – A proposal for further actions

Over the recent years, EU chemicals legislation, guidance and test guidelines have been developed or adapted for nanomaterials to facilitate safe use of nanomaterials. This paper provides an overview of the information requirements across different EU regulatory areas. For each information requirement, a group of 22 experts identified potential needs for further action to accommodate guidance and test guidelines to nanomaterials. Eleven different needs for action were identified, capturing twenty-two information requirements that are specific to nanomaterials and relevant to multiple regulatory areas. These were further reduced to three overarching issues: 1) resolve issues around nanomaterial dispersion stability and dosing in toxicity testing, in particular for human health endpoints, 2) further develop tests or guidance on degradation and transformation of organic nanomaterials or nanomaterials with organic components, and 3) further develop tests and guidance to measure (a)cellular reactivity of nanomaterials. Efforts towards addressing these issues will result in better fit-for-purpose test methods for (EU) regulatory compliance. Moreover, it secures validity of hazard and risk assessments of nanomaterials. The results of the study accentuate the need for a structural process of identification of information needs and knowledge generation, preferably as part of risk governance and closely connected to technological innovation policy.

Current situation and future prognosis of health, safety and environment risk assessment of nanomaterials in South Africa

The commercialisation and everyday use of nanomaterials and nanomaterial-enabled products (NEPs) is rising year-on-year. Responsible development of nanotechnology includes understanding their potential implications on health, safety, and the environment (HSE). The health risk assessment of nanomaterials has therefore become one of the major activities of international agencies including the Organisation for Economic Co-operation and Development and the Environmental Protection Agency for protection of human health and the environment. Nationally, with the foresight and the leadership of the Department of Science and Innovation, a HSE programme was initiated to establish the necessary infrastructure to conduct the tests in the hazard identification and exposure assessment that are needed in the risk assessment of nanomaterials synthesised as well as NEPs available in South Africa. Here we present the advances that have been made in elucidating the different facets that are required when undertaking risk assessments of nanomaterials, i.e. physicochemical characterisation, hazard identification, exposure assessment and effects assessment. These facets are increasingly being considered throughout the nanomaterials present in the life cycles of NEPs. South Africa's research contribution to an international understanding of HSE risks of nanomaterials is highlighted and the future direction to generate the necessary information for effective risk communication and management is provided. This will assist in ensuring safer innovation of nanotechnology in South Africa and support the export of locally manufactured nanomaterials as per international requirements.Significance: Significant contributions of South Africa to the nanomaterial HSE knowledge base are highlighted. Development of standardised testing methodologies in nanomaterial HSE and protection of human and ecological health through risk assessment of nanomaterials are discussed. This paper contributes to ensuring safer innovation of nanotechnology in South Africa.

Different Sensitivity of Advanced Bronchial and Alveolar Mono- and Coculture Models for Hazard Assessment of Nanomaterials.

For the next-generation risk assessment (NGRA) of chemicals and nanomaterials, new approach methodologies (NAMs) are needed for hazard assessment in compliance with the 3R's to reduce, replace and refine animal experiments. This study aimed to establish and characterize an advanced respiratory model consisting of human epithelial bronchial BEAS-2B cells cultivated at the air-liquid interface (ALI), both as monocultures and in cocultures with human endothelial EA.hy926 cells. The performance of the bronchial models was compared to a commonly used alveolar model consisting of A549 in monoculture and in coculture with EA.hy926 cells. The cells were exposed at the ALI to nanosilver (NM-300K) in the VITROCELL® Cloud. After 24 h, cellular viability (alamarBlue assay), inflammatory response (enzyme-linked immunosorbent assay), DNA damage (enzyme-modified comet assay), and chromosomal damage (cytokinesis-block micronucleus assay) were measured. Cytotoxicity and genotoxicity induced by NM-300K were dependent on both the cell types and model, where BEAS-2B in monocultures had the highest sensitivity in terms of cell viability and DNA strand breaks. This study indicates that the four ALI lung models have different sensitivities to NM-300K exposure and brings important knowledge for the further development of advanced 3D respiratory in vitro models for the most reliable human hazard assessment based on NAMs.