37 research outputs found

    Comparing BMD-derived genotoxic potency estimations across variants of the transgenic rodent gene mutation assay.

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    There is growing interest in quantitative analysis of in vivo genetic toxicity dose-response data, and use of point-of-departure (PoD) metrics such as the benchmark dose (BMD) for human health risk assessment (HHRA). Currently, multiple transgenic rodent (TGR) assay variants, employing different rodent strains and reporter transgenes, are used for the assessment of chemically-induced genotoxic effects in vivo. However, regulatory issues arise when different PoD values (e.g., lower BMD confidence intervals or BMDLs) are obtained for the same compound across different TGR assay variants. This study therefore employed the BMD approach to examine the ability of different TGR variants to yield comparable genotoxic potency estimates. Review of over 2000 dose-response datasets identified suitably-matched dose-response data for three compounds (ethyl methanesulfonate or EMS, N-ethyl-N-nitrosourea or ENU, and dimethylnitrosamine or DMN) across four commonly-used murine TGR variants (Muta™Mouse lacZ, Muta™Mouse cII, gpt delta and BigBlue® lacI). Dose-response analyses provided no conclusive evidence that TGR variant choice significantly influences the derived genotoxic potency estimate. This conclusion was reliant upon taking into account the importance of comparing BMD confidence intervals as opposed to directly comparing PoD values (e.g., comparing BMDLs). Comparisons with earlier works suggested that with respect to potency determination, tissue choice is potentially more important than choice of TGR assay variant. Scoring multiple tissues selected on the basis of supporting toxicokinetic information is therefore recommended. Finally, we used typical within-group variances to estimate preliminary endpoint-specific benchmark response (BMR) values across several TGR variants/tissues. We discuss why such values are required for routine use of genetic toxicity PoDs for HHRA. Environ. Mol. Mutagen. 58:632-643, 2017. © 2017 Her Majesty the Queen in Right of Canada. Environmental and Molecular Mutagenesis Published by Wiley Periodicals, Inc

    Challenges in predicting the change in the cumulative exposure of new tobacco and related products based on emissions and toxicity dose–response data

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    Funding: This work was funded by the Netherlands Food and Consumer Product Safety Authority (NVWA), Utrecht, the Netherlands. Project number 9.7.1Many novel tobacco products have been developed in recent years. Although many may emit lower levels of several toxicants, their risk in the long term remains unclear. We previously published a method for the exposure assessment of mixtures that can be used to compare the changes in cumulative exposure to carcinogens among tobacco products. While further developing this method by including more carcinogens or to explore its application to non-cancer endpoints, we encountered a lack of data that are required for better-substantiated conclusions regarding differences in exposure between products. In this special communication, we argue the case for more data on adverse health effects, as well as more data on the composition of the emissions from tobacco products. Such information can be used to identify significant changes in relevance to health using the cumulative exposure method with different products and to substantiate regulatory decisions.Publisher PDFPeer reviewe

    Workshop on Regulatory Preparedness for Innovation in Nanotechnology

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    This report summarises the presentations and discussions at the first NanoReg2 Workshop on Regulatory Preparedness for Innovation in Nanotechnology held in Ispra, Italy 5 to 6 October 2017 and attended by approximately 60 regulators, industry representatives and other stakeholders. NanoReg2 is a European Union (EU) Horizon 2020 project. At the workshop, Regulatory Preparedness was defined as the regulators' timely awareness of innovations and the regulator's actions to check whether present legislation covers all safety aspects of each innovation, including initiating revision of the legislation as appropriate. Regulatory Preparedness, and Safe-by-Design (SbD) jointly constitute the NanoReg2 Safe Innovation Approach (SIA) for developing innovative products based on nanotechnology. The workshop aimed to gather views and identify current practices in regulatory work on safety of innovative products, tools already in use or needed, and potential difficulties in implementing Regulatory Preparedness in the EU. Presentations addressed the current state of the safety of nanotechnology innovation. The viewpoints included the regulatory framework, the principles behind it and the agencies and authorities enforcing it; nanosafety research projects and their support system (e.g. the current EU Horizon 2020 Framework Programme); national nanosafety initiatives; and the development of tools, such as foresight tools and harmonised test guidelines by the OECD for data generation. The workshop served to generate ideas for achieving Regulatory Preparedness. The participants recognised that while regulators deal with the safety of innovations, only few systematic approaches to this work exist. Some innovative products may reach the market before their safety has been appropriately assessed, as illustrated by RAPEX, the Rapid Exchange of Information System. A continuous and proactive combination of interconnected activities was considered to be required for ensuring Regulatory Preparedness. Thus, anticipation, e.g. horizon scanning, was seen as important, as was communication between regulators, innovators (industry) and other stakeholders. Regulators need to become aware of innovative products under development to ensure that the legislation and methods for safety assessment are available and adequate. Innovators must be aware of regulatory requirements and their likely development. This mutual awareness helps to develop safe products and to avoid delays or other problems in obtaining market approval. Awareness can be achieved through communication, which requires trust, e.g. promoted via "trusted environments" for confidential inquiries and information sharing. Furthermore, regulators need early access to the existing information and data relevant to safety assessment of innovative products to provide timely guidance and advice to Industry as well as to develop strategies for dealing with uncertainty, e.g. by applying the precautionary principle. Regulatory Preparedness was discussed as part of the SIA, and a "road map" of actions was suggested and outlined. The workshop has thus contributed towards acceptance of implementing Regulatory Preparedness for innovation in nanotechnology through the participation of a variety of stakeholders. This paves the way for a better dialogue among stakeholders in a fast economic development cycle, where it is even more important to quickly identify emerging needs for new approaches to regulatory issues for innovationJRC.F.2-Consumer Products Safet
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