Current status and future challenges of genotoxicity OECD Test Guidelines for nanomaterials: a workshop report.

Genotoxicity testing for nanomaterials remains challenging as standard testing approaches require some adaptation, and further development of nano-specific OECD Test Guidelines (TGs) and Guidance Documents (GDs) are needed. However, the field of genotoxicology continues to progress and new approach methodologies (NAMs) are being developed that could provide relevant information on the range of mechanisms of genotoxic action that may be imparted by nanomaterials. There is a recognition of the need for implementation of new and/or adapted OECD TGs, new OECD GDs, and utilization of NAMs within a genotoxicity testing framework for nanomaterials. As such, the requirements to apply new experimental approaches and data for genotoxicity assessment of nanomaterials in a regulatory context is neither clear, nor used in practice. Thus, an international workshop with representatives from regulatory agencies, industry, government, and academic scientists was convened to discuss these issues. The expert discussion highlighted the current deficiencies that exist in standard testing approaches within exposure regimes, insufficient physicochemical characterization, lack of demonstration of cell or tissue uptake and internalization, and limitations in the coverage of genotoxic modes of action. Regarding the latter aspect, a consensus was reached on the importance of using NAMs to support the genotoxicity assessment of nanomaterials. Also highlighted was the need for close engagement between scientists and regulators to (i) provide clarity on the regulatory needs, (ii) improve the acceptance and use of NAM-generated data, and (iii) define how NAMs may be used as part of weight of evidence approaches for use in regulatory risk assessments.

SCCS scientific opinion on Butylated hydroxytoluene (BHT) - SCCS/1636/21.

OPINION TO BE CITED AS: SCCS (Scientific Committee on Consumer Safety), scientific opinion on Butylated hydroxytoluene (BHT), preliminary version of September 27, 2021, final version of December 2, 2021, SCCS/1636/21.

SCCS Scientific Opinion on Acid Yellow 3 (submission II) - SCCS/1631/21.

Opinion to be cited as: SCCS (Scientific Committee on Consumer Safety), Opinion on Acid Yellow 3 - C054 (CAS Number 8004-92-0, EC No 305-897-5), submission II, preliminary version of 7 May 2021, final version of 23 July 2021, SCCS/1631/21.

A call for action on the development and implementation of new methodologies for safety assessment of chemical-based products in the EU - A short communication.

Safety assessment of chemicals and products in the European Union (EU) is based on decades of practice using primarily animal toxicity studies to model hazardous effects in humans. Nevertheless, there has been a long-standing ethical concern about using experimental animals. In addition, animal models may fail to predict adverse effects in humans. This has provided a strong motivation to develop and use new approach methodologies and other alternative sources of evidence. A key challenge for this is integration of evidence from different sources. This paper is a call for action with regard to development, validation, and implementation of modern safety assessment approaches for human health assessment by means of focused applied research and development with three strands: (a) to improve screening and priority setting, (b) to enhance and partially replace animal studies under the current regulatory schemes and eventually (c) to fully replace animal studies, while achieving at least the same level of protection. For this gradual but systematic replacement of animal studies, a long-term concerted and coordinated effort with clear goals is needed at EU level, as a societal and political choice, to plan and motivate research and innovation in regulatory safety assessment.

The SCCS scientific advice on the safety of nanomaterials in cosmetics.

The Cosmetic Regulation (EC) No 1223/2009 specifically covers the risk of nanomaterials used in cosmetic products. If there are concerns regarding the safety of a nanomaterial, the European Commission refers it to the SCCS for a scientific opinion. The Commission mandated the SCCS to identify the scientific basis for safety concerns that could be used as a basis for identifying and prioritising nanomaterials for safety assessment, and to revisit previous inconclusive SCCS opinions on nanomaterials to identify any concerns for potential risks to the consumer health. The SCCS Scientific Advice identified the key general aspects of nanomaterials that should raise a safety concern for a safety assessor/manager, so that the nanomaterial(s) in question could be subjected to safety assessment to establish safety to the consumer. The Advice also developed a list of the nanomaterials notified to the Commission for use in cosmetics in an order of priority for safety assessment, and revisited three previous inconclusive opinions on nanomaterials to highlight concerns over consumer safety that merited further safety assessment.

Risk Governance of Emerging Technologies Demonstrated in Terms of its Applicability to Nanomaterials.

Nanotechnologies have reached maturity and market penetration that require nano-specific changes in legislation and harmonization among legislation domains, such as the amendments to REACH for nanomaterials (NMs) which came into force in 2020. Thus, an assessment of the components and regulatory boundaries of NMs risk governance is timely, alongside related methods and tools, as part of the global efforts to optimise nanosafety and integrate it into product design processes, via Safe(r)-by-Design (SbD) concepts. This paper provides an overview of the state-of-the-art regarding risk governance of NMs and lays out the theoretical basis for the development and implementation of an effective, trustworthy and transparent risk governance framework for NMs. The proposed framework enables continuous integration of the evolving state of the science, leverages best practice from contiguous disciplines and facilitates responsive re-thinking of nanosafety governance to meet future needs. To achieve and operationalise such framework, a science-based Risk Governance Council (RGC) for NMs is being developed. The framework will provide a toolkit for independent NMs' risk governance and integrates needs and views of stakeholders. An extension of this framework to relevant advanced materials and emerging technologies is also envisaged, in view of future foundations of risk research in Europe and globally.

HIV and shifting epicenters for COVID-19, an alert for some countries.

Were southern hemisphere countries right to undertake national lockdown during their summer time? Were they right to blindly follow the self-isolation wave that hit European countries in full winter? As a southern hemisphere country like South Africa stands now as the most COVID-19 and HIV affected country in Africa, we use in this paper, recent COVID-19 data to provide a statistical and comparative analysis that may alert southern hemisphere countries entering the winter season. After that, we use a generalized simple mathematical model of HIV-COVID-19 together with graphs, curves and tables to compare the pandemic situation in countries that were once the epicenter of the disease, such as China, Italy, Spain, United Kingdom (UK) and United States of America (USA). We perform stability and bifurcation analysis and show that the model contains a forward and a backward bifurcation under certain conditions. We also study different scenarios of stability/unstability equilibria for the model. The fractional (generalized) COVID-19 model is solved numerically and a predicted prevalence for the COVID-19 is provided. Recall that Brazil and South Africa share number of similar social features like Favellas (Brazil) and Townships (South Africa) with issues like promiscuity, poverty, and where social distanciation is almost impossible to observe. We can now ask the following question: Knowing its HIV situation, is South Africa the next epicenter in weeks to come when winter conditions, proven to be favorable to the spread of the new coronavirus are comfily installed?

Emerging technologies for food and drug safety.

Emerging technologies are playing a major role in the generation of new approaches to assess the safety of both foods and drugs. However, the integration of emerging technologies in the regulatory decision-making process requires rigorous assessment and consensus amongst international partners and research communities. To that end, the Global Coalition for Regulatory Science Research (GCRSR) in partnership with the Brazilian Health Surveillance Agency (ANVISA) hosted the seventh Global Summit on Regulatory Science (GSRS17) in Brasilia, Brazil on September 18-20, 2017 to discuss the role of new approaches in regulatory science with a specific emphasis on applications in food and medical product safety. The global regulatory landscape concerning the application of new technologies was assessed in several countries worldwide. Challenges and issues were discussed in the context of developing an international consensus for objective criteria in the development, application and review of emerging technologies. The need for advanced approaches to allow for faster, less expensive and more predictive methodologies was elaborated. In addition, the strengths and weaknesses of each new approach was discussed. And finally, the need for standards and reproducible approaches was reviewed to enhance the application of the emerging technologies to improve food and drug safety. The overarching goal of GSRS17 was to provide a venue where regulators and researchers meet to develop collaborations addressing the most pressing scientific challenges and facilitate the adoption of novel technical innovations to advance the field of regulatory science.

Aligning nanotoxicology with the 3Rs: What is needed to realise the short, medium and long-term opportunities?

Nanomaterials convey numerous advantages, and the past decade has seen a considerable rise in their development and production for an expanse of applications. While the potential advantages of nanomaterials are clear, concerns over the impact of human and environmental exposure exist. Concerted, science-led efforts are required to understand the effects of nanomaterial exposure and ensure that protection goals are met. There is much on-going discussion regarding how best to assess nanomaterial risk, particularly considering the large number of tests that may be required. A plethora of forms may need to be tested for each nanomaterial, and risk assessed throughout the life cycle, meaning numerous acute and chronic toxicity studies could be required, which is neither practical nor utilises the current evidence-base. Hence, there are scientific, business, ethical and legislative drivers to re-consider the use of animal toxicity tests. An expert Working Group of regulators, academics and industry scientists were gathered by the UK's NC3Rs to discuss: i) opportunities being offered in the short, medium and long-terms to advance nanosafety, ii) how to align these advances with the application of the 3Rs in nanomaterial safety testing, and iii) shifting the focus of risk assessment from current hazard-based approaches towards exposure-driven approaches.

A uniform measurement expression for cross method comparison of nanoparticle aggregate size distributions.

Available measurement methods for nanomaterials are based on very different measurement principles and hence produce different values when used on aggregated nanoparticle dispersions. This paper provides a solution for relating measurements of nanomaterials comprised of nanoparticle aggregates determined by different techniques using a uniform expression of a mass equivalent diameter (MED). The obtained solution is used to transform into MED the size distributions of the same sample of synthetic amorphous silica (nanomaterial comprising aggregated nanoparticles) measured by six different techniques: scanning electron microscopy in both high vacuum (SEM) and liquid cell setup (Wet-SEM); gas-phase electrophoretic mobility molecular analyzer (GEMMA); centrifugal liquid sedimentation (CLS); nanoparticle tracking analysis (NTA); and asymmetric flow field flow fractionation with inductively coupled plasma mass spectrometry detection (AF4-ICP-MS). Transformed size distributions are then compared between the methods and conclusions drawn on methods' measurement accuracy, limits of detection and quantification related to the synthetic amorphous silca's size. Two out of the six tested methods (GEMMA and AF4-ICP-MS) cross validate the MED distributions between each other, providing a true measurement. The measurement accuracy of other four techniques is shown to be compromised either by the high limit of detection and quantification (CLS, NTA, Wet-SEM) or the sample preparation that is biased by increased retention of smaller nanomaterials (SEM). This study thereby presents a successful and conclusive cross-method comparison of size distribution measurements of aggregated nanomaterials. The authors recommend the uniform MED size expression for application in nanomaterial risk assessment studies and clarifications in current regulations and definitions concerning nanomaterials.

Using Human Biomonitoring Data to Support Risk Assessment of Cosmetic Ingredients-A Case Study of Benzophenone-3.

Safety assessment of UV filters for human health by the Scientific Committee on Consumer Safety (SCCS) is based on the estimation of internal dose following external (skin) application of cosmetic products, and comparison with a toxicological reference value after conversion to internal dose. Data from human biomonitoring (HBM) could be very useful in this regard, because it is based on the measurement of real-life internal exposure of the human population to a chemical. UV filters were included in the priority list of compounds to be addressed under the European Human Biomonitoring Initiative (HBM4EU), and risk assessment of benzophenone-3 (BP-3) was carried out based on HBM data. Using BP-3 as an example, this study investigated the benefits and limitations of the use of external versus internal exposure data to explore the usefulness of HBM to support the risk assessment of cosmetic ingredients. The results show that both approaches did indicate a risk to human health under certain levels of exposure. They also highlight the need for more robust exposure data on BP-3 and other cosmetic ingredients, and a standardized framework for incorporating HBM data in the risk assessment of cosmetic products.

Ecotoxicological and regulatory aspects of environmental sustainability of nanopesticides.

Recent years have seen the development of various colloidal formulations of pesticides and other agrochemicals aimed at use in sustainable agriculture. These formulations include inorganic, organic or hybrid particulates, or nanocarriers composed of biodegradable polymers, that can provide a better control of the release of active ingredients. The very small particle sizes and high surface areas of nanopesticides may however also lead to some unintended (eco)toxicological effects due to the way in which they interact with the target and non-target species and the environment. The current level of knowledge on ecotoxicological effects of nanopesticides is scarce, especially in regard to the fate and behaviour of such formulations in the environment. Nanopesticides will however have to cross a stringent regulatory scrutiny before marketing in most countries for health and environmental risks under a range of regulatory frameworks that require pre-market notification, risk assessment and approval, followed by labelling, post-market monitoring and surveillance. This review provides an overview of the key regulatory and ecotoxicological aspects relating to nanopesticides that will need to be considered for environmentally-sustainable use in agriculture.

Guidance on technical requirements for regulated food and feed product applications to establish the presence of small particles including nanoparticles.

Following a mandate from the European Commission, EFSA has developed a Guidance on Technical Requirements (Guidance on Particle-TR), defining the criteria for assessing the presence of a fraction of small particles, and setting out information requirements for applications in the regulated food and feed product areas (e.g. novel food, food/feed additives, food contact materials and pesticides). These requirements apply to particles requiring specific assessment at the nanoscale in conventional materials that do not meet the definition of engineered nanomaterial as set out in the Novel Food Regulation (EU) 2015/2283. The guidance outlines appraisal criteria grouped in three sections, to confirm whether or not the conventional risk assessment should be complemented with nanospecific considerations. The first group addresses solubility and dissolution rate as key physicochemical properties to assess whether consumers will be exposed to particles. The second group establishes the information requirements for assessing whether the conventional material contains a fraction or consists of small particles, and its characterisation. The third group describes the information to be presented for existing safety studies to demonstrate that the fraction of small particles, including particles at the nanoscale, has been properly evaluated. In addition, in order to guide the appraisal of existing safety studies, recommendations for closing the data gaps while minimising the need for conducting new animal studies are provided. This Guidance on Particle-TR complements the Guidance on risk assessment of nanomaterials to be applied in the food and feed chain, human and animal health updated by the EFSA Scientific Committee as co-published with this Guidance. Applicants are advised to consult both guidance documents before conducting new studies.

Guidance on risk assessment of nanomaterials to be applied in the food and feed chain: human and animal health.

The EFSA has updated the Guidance on risk assessment of the application of nanoscience and nanotechnologies in the food and feed chain, human and animal health. It covers the application areas within EFSA's remit, including novel foods, food contact materials, food/feed additives and pesticides. The updated guidance, now Scientific Committee Guidance on nano risk assessment (SC Guidance on Nano-RA), has taken account of relevant scientific studies that provide insights to physico-chemical properties, exposure assessment and hazard characterisation of nanomaterials and areas of applicability. Together with the accompanying Guidance on Technical requirements for regulated food and feed product applications to establish the presence of small particles including nanoparticles (Guidance on Particle-TR), the SC Guidance on Nano-RA specifically elaborates on physico-chemical characterisation, key parameters that should be measured, methods and techniques that can be used for characterisation of nanomaterials and their determination in complex matrices. The SC Guidance on Nano-RA also details aspects relating to exposure assessment and hazard identification and characterisation. In particular, nanospecific considerations relating to in vitro/in vivo toxicological studies are discussed and a tiered framework for toxicological testing is outlined. Furthermore, in vitro degradation, toxicokinetics, genotoxicity, local and systemic toxicity as well as general issues relating to testing of nanomaterials are described. Depending on the initial tier results, additional studies may be needed to investigate reproductive and developmental toxicity, chronic toxicity and carcinogenicity, immunotoxicity and allergenicity, neurotoxicity, effects on gut microbiome and endocrine activity. The possible use of read-across to fill data gaps as well as the potential use of integrated testing strategies and the knowledge of modes or mechanisms of action are also discussed. The Guidance proposes approaches to risk characterisation and uncertainty analysis.

The way forward for assessing the human health safety of cosmetics in the EU - Workshop proceedings.

Although the need for non-animal alternatives has been well recognised for the human health hazard assessment of chemicals in general, it has become especially pressing for cosmetic ingredients due to the full implementation of testing and marketing bans on animal testing under the European Cosmetics Regulation. This means that for the safety assessment of cosmetics, the necessary safety data for both the ingredients and the finished product can be drawn from validated (or scientifically-valid), so-called "Replacement methods". In view of the challenges for safety assessment without recourse to animal test data, the Methodology Working Group of the Scientific Committee on Consumer Safety organised a workshop in February 2019 to discuss the key issues in regard to the use of animal-free alternative methods for the safety evaluation of cosmetic ingredients. This perspective article summarises the outcomes of this workshop and reflects on the state-of-the-art and possible way forward for the safety assessment of cosmetic ingredients for which no experimental animal data exist. The use and optimisation of "New Approach Methodology" that could be useful tools in the context of the "Next Generation Risk Assessment" and the strategic framework for safety assessment of cosmetics were discussed in depth.

Considerations for environmental fate and ecotoxicity testing to support environmental risk assessments for engineered nanoparticles.

There is an increasing concern over the safety of engineered nanoparticles (ENPs) to humans and the environment and it is likely that the environmental risks of these particles will have to be tested under regulatory schemes such as REACH. Due to their unique properties and the fact that their detection and characterisation in complex matrices is challenging, existing analytical methods and test approaches for assessing environmental risk may not be appropriate for ENPs. In this article we discuss the challenges associated with the testing of ENPs to generate data on persistence, mobility, bioavailability and ecotoxicity in the environment. It is essential that careful consideration is given to the selection of the test material, the test system (including test vessels and study media) and the test exposure conditions. During a study it is critical that not only the concentration of the ENP is determined but also its characteristics (e.g. size, shape, degree of aggregation and dissolution). A range of analytical techniques is available including microscopy-based approaches (e.g transmission and scanning electron microscopy), dynamic light scattering, and size separation approaches (e.g. field flow fractionation and hydrodynamic chromatography) coupled to detection methods such as inductively coupled plasma MS. All of these have their disadvantages: some are unable to distinguish between ENPs and natural interferences; some techniques require sample preparation approaches that can introduce artefacts; and others are complex and time-consuming. A combination of techniques is therefore needed. Our knowledge in this area is still limited, and co-ordinated research is required to gain a better understanding of the factors and processes affecting ENP fate and effects in the environment as well as to develop more usable, robust and sensitive methods for characterisation and detection of ENPs in environmental systems.

A comparison of nanoparticle and fine particle uptake by Daphnia magna.

The use of nanoparticles in various applications is steadily on the rise, with use in a range of applications, including printer toner, sunscreen, medical imaging, and enhanced drug delivery. While research on human effects via, for example, inhalation is relatively well developed, the environmental assessment of nanoparticles is in its infancy. In the present study, we assessed the uptake and quantitative accumulation, as well as the depuration, of a model nanoparticle, a 20-nm fluorescent carboxylated polystyrene bead, in the aquatic invertebrate Daphnia magna and compared it to a larger, 1,000-nm particle. Using confocal microscopy, rapid accumulation in the gastrointestinal tract was observed within an hour of exposure to both particle sizes in both adults and neonates. Fluorescence could also be observed in the oil storage droplets, suggesting that both particle sizes have crossed the gut's epithelial barrier. Quantification of fluorescence of both sizes of particles showed that although uptake of the 20-nm particles was lower in terms of mass it was equal to or greater than 1000-nm particle uptake when expressed as surface area or particle number. Depuration was relatively rapid for the 1000-nm beads, decreasing by more than 90% over 4 h. In contrast, depuration of the 20-nm beads was less extensive, reaching 40% over 4 h. Transmission electron microscopy confirmed uptake of 1,000-nm beads, but uptake of 20-nm beads was inconclusive since similar-sized inclusions could be observed in control treatments.

Integrating in silico models and read-across methods for predicting toxicity of chemicals: A step-wise strategy.

In silico methods and models are increasingly used for predicting properties of chemicals for hazard identification and hazard characterisation in the absence of experimental toxicity data. Many in silico models are available and can be used individually or in an integrated fashion. Whilst such models offer major benefits to toxicologists, risk assessors and the global scientific community, the lack of a consistent framework for the integration of in silico results can lead to uncertainty and even contradictions across models and users, even for the same chemicals. In this context, a range of methods for integrating in silico results have been proposed on a statistical or case-specific basis. Read-across constitutes another strategy for deriving reference points or points of departure for hazard characterisation of untested chemicals, from the available experimental data for structurally-similar compounds, mostly using expert judgment. Recently a number of software systems have been developed to support experts in this task providing a formalised and structured procedure. Such a procedure could also facilitate further integration of the results generated from in silico models and read-across. This article discusses a framework on weight of evidence published by EFSA to identify the stepwise approach for systematic integration of results or values obtained from these "non-testing methods". Key criteria and best practices for selecting and evaluating individual in silico models are also described, together with the means to combining the results, taking into account any limitations, and identifying strategies that are likely to provide consistent results.