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To enhance productivity, aquaculture is intensifying, with high-density fish ponds and increased feed input, contributing to nutrient load and eutrophication. Climate change further exacerbates cyanobacterial blooms and cyanotoxin production that affect aquatic organisms and consumers. A review was conducted to outline this issue from its inception - eutrophication, cyanobacterial blooms, their harmful metabolites and consequential effects (health and economic) in aquacultures. The strength of evidence regarding the relationship between cyanobacteria/cyanotoxins and potential consequences in freshwater aquacultures (fish production) globally were assessed as well, while identifying knowledge gaps and suggesting future research directions. With that aim several online databases were searched through June 2023 (from 2000), and accessible publications conducted in aquacultures with organisms for human consumption, reflecting cyanotoxin exposure, were selected. Data on cyanobacteria/cyanotoxins in aquacultures and its products worldwide were extracted and analyzed. Selected 63 papers from 22 countries were conducted in Asia (48%), Africa (22%), America (22%) and Europe (8%). Microcystis aeruginosa was most frequent, among over 150 cyanobacterial species. Cyanobacterial metabolites (mostly microcystins) were found in aquaculture water and fish from 18 countries (42 and 33 papers respectively). The most affected were small and shallow fish ponds, and omnivorous or carnivorous fish species. Cyanotoxins were detected in various fish organs, including muscles, with levels exceeding the tolerable daily intake in 60% of the studies. The majority of research was done in developing countries, employing less precise detection methods, making the obtained values estimates. To assess the risk of human exposure, the precise levels of all cyanotoxins, not just microcystins are needed, including monitoring their fate in aquatic food chains and during food processing. Epidemiological research on health consequences, setting guideline values, and continuous monitoring are necessary as well. Further efforts should focus on methods for elimination, prevention, and education. [Display omitted] • 63 publications from 22 countries are reviewed. • The global "south" tropical zones burdened with increased dependence and climatic factors conducive for blooms. • The most affected are small and shallow fish ponds, omnivorous or carnivorous fish. • Cyanotoxin levels exceeding the tolerable daily intake in 60% of the studies. • Impossible to compare values due to imprecision and lack of validated testing. [ABSTRACT FROM AUTHOR]

Reverse Logistics (RL) of end-of-use/end-of-life products is a key approach for supporting the transition to a circular economy. However, lack of knowledge and experience in designing RL is one of the barriers for companies in implementing successful RL. This research proposes an RL support tool (RLST) for designing RL systems, developed through iterative cycles of theoretical development and empirical testing/feedback from potential users. The RLST builds upon the principles of configuration systems to adapt the various aspects of RL design into a knowledge base and, subsequently, into an Excel-based support tool - in addition to allowing companies to assess their motivation/driver and set the context (e.g., product characteristics, the existence and nature of Extended Producer Responsibility (EPR) legislation), it supports the design of the RL network/channel and other aspects such as stakeholder collaboration, legislation, consumer behaviour and incentives, use of digital technologies, key performance indicators and factors around governance/programme management. Such a tool can be helpful for practitioners in addressing the knowledge gaps, stimulating discussions among stakeholders for scenario building and for analysing how different scenarios might work. The research advances the knowledge on RL systems design for the circular economy along with, for the first time, building knowledge and application of configuration systems in the field of RL. [Display omitted] • Research outlines a Reverse Logistics (RL) tool theoretically and empirically designed from configuration principles • RL tool includes several dimensions (e.g., drivers, channels, stakeholders, regulations, incentives, governance and digital technologies) • Demonstrated approach to build a knowledge-base on RL for configuration of alternative concepts • Case studies demonstrate the usefulness of the RL tool to address knowledge gaps and build scenarios • Play book as support tool offers additional insights and aid decision-making in RL [ABSTRACT FROM AUTHOR]