Nonylphenol ethoxylates (NPnEOs) are non-ionic surfactants that have been widely used in the cleaning industry over the past decades. At the same time, they pose a major environmental threat due to their toxicity and estrogenic activity. During the wastewater treatment process, they degrade and form more persistent and toxic metabolites that are detected mainly in the plant effluent. In the present work headspace solid-phase microextraction (SPME) with in-sample derivatization was used with dimethyl sulfate as methylating agent in order to quantify nonylphenol ethoxylates in wastewater samples. The selection of the appropriate fiber coating material and the optimization of the desorption conditions were necessary in order to enhance the SPME performance. The analytes were successfully isolated using 65 μm PDMS/DVB fiber and they were separated by means of gas chromatography with mass spectrometry detector (GC/MS) with the injector at 270°C. The method was linear over a wide range of concentrations (0.05–4...

The circular economy paradigm can be beneficial for urban sustainability by eliminating waste and pollution, by circulating products and materials and by regenerating nature. Furthermore, under an urban circular development scheme, environmental noise can be designed out. The current noise control policies and actions, undertaken at a source–medium–receiver level, present a linearity with minimum sustainability co-benefits. A circular approach in noise control strategies and in soundscape design could offer numerous ecologically related co-benefits. The global literature documenting the advantages of the implementation of circular economy in cities has highlighted noise mitigation as a given benefit. Research involving circular economy actions such as urban green infrastructure, green walls, sustainable mobility systems and electro-mobility has acknowledged reduced noise levels as a major circularity outcome. In this research paper, we highlight the necessity of a circularity and bioeconomy approach in noise control. To this end, a preliminary experimental noise modeling study was conducted to showcase the acoustic benefits of green walls and electric vehicles in a medium-sized urban area of a Mediterranean island. The results indicate a noise level reduction at 4 dB(A) when simulating the introduction of urban circular development actions.

This research focuses on the management of food waste in small communities such as the one at the Reception and Identification Center (RIC) of Kara Tepe in Lesvos (Greece), using the method of home composting. To understand production patterns and possible variations of the characteristics of food residues, a sampling methodology was designed for obtaining representative samples of the whole population of the center. Two composting trials were carried out using household composters with a tailored active aeration system. The first trial contained food residues and olive leaves as a bulking agent (Κ1), and the second one contained food residues, olive leaves and two-phase olive pomace (K2) to investigate co-composting with local agricultural byproducts. Results indicate that the compost produced in the first trial (K1) was stable but phytotoxic and unsuitable for use as a soil amendment. The compost produced in the second trial (K2) was also stable and non-phytotoxic but potentially harmful for very sensitive plants if used as a soil amendment because of high pH values. In addition, an analysis of the operational cost of the proposed treatment process was performed, involving the estimation of electricity and water consumption. The findings indicate that 304 home composters can cover the requirements of a population of this size (approximately 1300 people), at a cost of a mere 3.36 €/day. Given the unique challenges faced by island communities in contrast to urban areas, including differences in strategy development, waste management practices, infrastructure, cultural considerations and innovation potential, the findings serve as a foundational guide for similar island communities in Mediterranean areas (for policy and decision makers, stakeholders, academia, etc.) to develop tailored strategies within the framework of the circular economy that particularly focus on composting for reducing food waste and utilizing byproducts. Therefore, it is feasible to exploit the proposed methodology in similar-sized communities—villages or even a block of flats—for the on-site treatment and utilization of food residues since it can provide a good-quality compost at a reasonable cost.

This study investigates the potential of several types of agro-industrial waste and residues for biogas production. There are significant quantities of agro-industrial waste generated on the island of Lesvos (Greece) that could significantly enhance the island’s energy balance and security. In this study, anaerobic digestion is studied using a variety of feedstocks and the feasibility of generating electricity from agro-industrial waste and residues is investigated. An inclusive analysis is provided to support a large-scale application and contribute towards the decarbonization of the island of Lesvos through the reduction of fossil fuel utilization. The main objective of this study is to investigate the potential of electricity production from different renewable energy sources, such as biogas, in Lesvos Island (Greece). It has been estimated that the total power production from biomass in Lesvos could reach up to 560 GWh, however there is a strict margin for the electricity produced from renewable sources for the non-interconnected islands in Greece.