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This Scientific Report was carried out in the context of the self‐task mandate (M‐2023‐00097) of the EFSA's Scientific Committee on 'Guidance on the use of biomarkers of effect in regulatory risk assessment of chemicals'. In the first phase, the project on biomarkers of effect started with a feasibility study (EFSA‐Q‐2024‐00128), with the intention to look closer at definitions and descriptions of biomarkers of effect, as well as to explore several concepts related to the context of application and other scientific principles to be further considered for its development. In addition, relevant activities, initiatives and knowledge in this area were collected and analysed within a complementary mapping study. The outcome of this phase aimed to create a structured basis for future guidance, to identify challenges and to recommend a way forward for its development. The recommendations refer especially to terminologies, the scope of the guidance and several scientific and technical aspects of the selection and interpretation of biomarkers of effect that need to be addressed in future guidance. Moreover, further recommendation refers to the collaborative process to be established with other regulatory organisations that should support the harmonisation and reduce divergencies in the application of methodologies across organisations or sectors. [ABSTRACT FROM AUTHOR]

This guidance on the assessment of dermal absorption has been developed to assist notifiers, users of test facilities and Member State authorities on critical aspects related to the setting of dermal absorption values to be used in risk assessments of active substances in Plant Protection Products (PPPs). It is based on the ‘scientific opinion on the science behind the revision of the guidance document on dermal absorption’ issued in 2011 by the EFSA Panel on Plant Protection Products and their Residues (PPR). The guidance refers to the EFSA PPR opinion in many instances. In addition, the first version of this guidance, issued in 2012 by the EFSA PPR Panel, has been revised in 2017 on the basis of new available data on human in vitro dermal absorption for PPPs and wherever clarifications were needed. Basic details of experimental design, available in the respective test guidelines and accompanying guidance for the conduct of studies, have not been addressed but recommendations specific to performing and interpreting dermal absorption studies with PPPs are given. Issues discussed include a brief description of the skin and its properties affecting dermal absorption. To facilitate use of the guidance, flow charts are included. Guidance is also provided, for example, when there are no data on dermal absorption for the product under evaluation. Elements for a tiered approach are presented including use of default values, data on closely related products, in vitro studies with human skin (regarded to provide the best estimate), data from experimental animals (rats) in vitro and in vivo, and the so called ‘triple pack’ approach. Various elements of study design and reporting that reduce experimental variation and aid consistent interpretation are presented. A proposal for reporting data for assessment reports is also provided. The issue of nanoparticles in PPPs is not addressed. Data from volunteer studies have not been discussed since their use is not allowed in EU for risk assessment of PPPs.This publication is linked to the following EFSA Supporting Publications article: http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2017.EN-1250/full [ABSTRACT FROM AUTHOR]

The structures of the title compounds 2, 5 and 6 were determined by single crystal X-ray methods at room temperature ( 2) and at 140 K ( 5 and 6). The molecules contain approximately planar CNO (or CNOS) groups with considerable C-N, C-O and C-S-π-bonding. The C-C bond distances in the four membered rings of the 2,4-bisamides (squaraines) 5 and 6 vary between 143.9 (6) and 146.9 with a mean value of 145.8 pm. In the 3,4-bisamide 2 the cyclobutendionestructure is more pronounced with d(C-C) ranging from 142.5 (4) to 148.8 (5) pm. The packing mode of 2, 5 and 6 are related by group-subgroup relations. [ABSTRACT FROM AUTHOR]