Incorporating sewage sludge (SS) into soils presents a cost-effective and environmentally friendly option compared to conventional farming practices. However, SS could be perceived as a double-edged sword, as it may contain a broad spectrum of contaminants, posing threats to soil, underground waters, food chains and human health. Even from an epidemiology perspective, the COVID-19 pandemic has instigated debates regarding the potential health risks associated with SS. The handling of SS is emerging as a significant issue in the European Union (EU), primarily due to its increasing utilization and the presence of contaminants such as heavy metals (HMs), microplastics (MPs), Pharmaceuticals in the Environment (PIE), and personal care products (PSPs). The Council Directive 86/278/EEC governs the limits of HMs when SS is utilized in agriculture. However, the Directive is enacted diversely throughout EU member states (MS), with their national legislations highlighting differences, gaps and various approaches in implementing the Council Directive. The Directive, which has been in force since 1986, has not undergone any significant revisions until the recent disclosure of a revised version in May 2023. The executive summary of the evaluation of the Council Directive 86/278/EEC (SWD-2023) – {final 158} specifies maximum concentrations of six HMs in SS among its regulatory measures. This article delves into capturing the current legal framework that defines and delimits the processes and obligations of EU MS regarding SS's management, treatment, and agriculture amendment. The primary objective is to explore the qualitative and quantitative differences/discrepancies between the MS National legislation and point out discontinuities and gaps, thus setting forward a cohesive step for future revisions and updates of the relevant legislation. Part of the article's results reflect the different approaches to permissible limits of HMs concentrations in the EU MS and between international organizations such as the Food and Agriculture Organization (FAO) and the World Health Organization (WHO). Moreover, the total absence of MPs and other Common Soil Pollutants (antibiotics, pharmaceuticals, etc.) limit values are evidence of the gaps in the current legislative framework.

Based on literature data, an analysis was conducted on the thermodynamic and kinetic dependencies of the thermal decomposition of methane. Course of this process was analysed for both thermal and thermal-catalytic conditions. The elementary reaction, i.e. the synthesis of methane from its elements, including its reversibility, was used as the basis for the for considerations on the kinetic model. The conversion degree was adopted as the kinetic parameter (kinetic variable) since this measure is essential for determining the amount of carbon deposit formed and thus closing the mass balance of this process. Several different kinetic models for the elementary reaction were analysed to determine how do they relate in regard to the constant of the reaction rate. It was determined that regardless of whether the process is catalytic or purely thermal, for temperatures t>900°C, the influence of reversibility of the reaction, has negligible influence on the yield of hydrogen produced, and thus can be omitted from the kinetic models. Special attention was given to iron-based catalysts, analysing the reactivity of Fe/C systems. It was demonstrated that the determined kinetic parameters satisfy the Kinetic Compensation Effect (KCE). Furthermore, by incorporating elements of Transition State Theory (TST), the existence of Entropy-Enthalpy Compensation (EEC) was highlighted. Based on these findings Authors show that through analysis of the changes in activation energy (E=20–421 kJ·mol-1) only an estimate of the optimal process conditions can be found, because the isoconversional temperature is also dependent on the way in which the reaction is conducted (T_{iso}=1200-1450K\ >\ \ T_{eq}). In other words, it was found that strong influences of such factors as T, P, etc. can locally compensate each other. Finally, it was also shown that the relations between KCE and EEC complement each other, which is confirmed by the determined average activation entropy at the isokinetic temperature (∆SB= -275.0 J·(mol·K)-1).

Carbapenemase-producing Enterobacter spp. Serratia marcescens, Citrobacter freundii, Providencia spp. and Morganella morganii (CP-ESCPM) are increasingly identified as causative agents of nosocomial infections but are still not under systematic genomic surveillance. In this study, using a combination of whole genome sequencing and conjugation experiments, we sought to elucidate the genomic characteristics and transferability of resistance genes in clinical CP-ESCPM isolates from Bulgaria. Among the 36 sequenced isolates, NDM-1 (12/36), VIM-4 (11/36), VIM-86 (8/36) and OXA-48 (7/36) carbapenemases were identified; two isolates carried both NDM-1 and VIM-86. The majority of carbapenemase genes were found on self-conjugative plasmids. IncL plasmids were responsible for the spread of OXA-48 among E. hormaechei, C. freundii and S. marcescens. IncM2 plasmids were generally associated with the spread of NDM-1 in C. freundii and S. marcescens, and also of VIM-4 in C. freundii. IncC plasmids were involved in the spread of the recently described VIM-86 in P. stuartii isolates. IncC plasmids carrying blaNDM-1 and blaVIM-86 have been observed too. blaNDM-1 was also detected on IncX3 in S. marcescens and on IncT plasmid in M. morganii. The significant resistance transfer rates highlight the role of the ESCPM group as a reservoir of resistance determinants and stress the need for strengthening the infection control measures.