Background The main goal of the paper is to review the existing state and propose a model solution for the introduction of the waste-to-energy concept in the Republic of Serbia and Bosnia and Herzegovina, as these Balkan countries are a source of high pollution due to the inefficient use of fossil fuels and the operation of coal-fired power plants. Besides, these countries have very low level of waste management, which results in the uncontrolled disposal of a large amount of waste which consists of plastic and microplastic materials which are difficult to decompose in natural ecosystems. Methods Considering the type and objectives of the study, a mixed research method was chosen as a combination of exploratory research, descriptive research, explanatory research, and modeling. Results The main result of the research shows the unfavorable situation in the field of waste management in the Republic of Serbia, as well as in Bosnia and Herzegovina. Both countries have adopted adequate strategies and plans, but waste management is not implemented accordingly, Nevertheless, numerous problems create considerable opportunities for improvement, especially regarding the potential for energy production from waste, which is an important approach to implementing the circular economy model. The study showed that the situation is particularly unfavorable in rural areas. Hence, the research proposes (a) a novel model for waste-to-energy governance and (b) a novel model for waste-to-energy management in rural areas. The research was done, and models were developed based on the examples of the Republic of Serbia, and Bosnia and Herzegovina. However, the results can be used in countries with a similar level of waste management and with a larger share of rural areas. Conclusions The paper emphasizes the importance of a holistic and systemic approach to waste management, with emphasis on using waste-to-energy concept as particularly applicable in the transition to circular economy. This study proposes a model for the integration of waste management (with emphasis on plastic and microplastic) and energy efficiency, presenting a model of approach that can be used in countries that are at the beginning of introducing a circular economy.

Abstract Polycyclic aromatic hydrocarbons (PAHs) are formed from anthropogenic activities, i.e. industrial emissions, incomplete combustion of petroleum, coal and other fossil fuels and other industrial and domestic activities. Research areas of this study are four representative locations in the industrial complex, in the city of Banja Luka, Republic of Srpska, Bosnia and Herzegovina. The main objective of the paper is to determine the ecological risk and to assess probable sources of PAHs contamination in soil and groundwater. The results of this study reflect the effects of coal combustion (pyrogenic origin), petrogenic and biomass origin and may provide basic data for the remediation of PAHs in the location. The ecological risk in soil (at depths of 30, 100, 200, 300 and 400 cm) and groundwater is determined. The mean values of ecological risk in soil and groundwater decreased with soil depth. Values of RQ(NCs) for groundwater were found at high ecological risk, for Ant, Chr, DahA, Acy, Pyr, BaA, Phe, Flo, Nap, Ace and Fluo, with values 28.57, 20.59, 300.00, 242.86, 185.71, 1700.0, 76.67, 53.33, 15.83, 100.00 and 57.14, respectively. ∑16PAH indicated high ecological risk for most PAHs, which decreased with soil depth. The value of RQ(NCs) for ΣPAHs in groundwater indicates high ecological risk (ΣPAHs ≥ 800 and RQ(MPCs) ≥ 1). This is the first study on the ecological risk of PAHs in soil and groundwater in industrial soils in Banja Luka and provides baseline information for further studies and additional investigations of this industrial complex.

For hospital personnel, a number of harmful chemicals exist. The paper deal with very different harmful chemicals, but all chemicals are important and continuing problems where the risks to health, if uncontrolled, are serious. In the research was used descriptive statistical operations and multivariate statistical method, factor analysis (FA), i.e. principal component analysis (PCA). An analysis of 24 organic and inorganic parameters was performed. Results of the correlation analysis suggest that these pollutants pairs might have similar sources or have been affected by similar factors. PCA she confirmed that the mutually correlated elements constitute a group of elements with a similar origin.

Rapid science and technology development, as well as population growth and solving global problems require a different approach to considering and solving these problems by including many scientific disciplines or technologies. The growing amount of waste and unsystematic depletion of natural resources impose new concepts and tools in creating new environmental products. The existing linear economy, based on the ‘take, make and dispose’ principle, is being replaced by a new approach, the ‘circular economy’. A circular economy seeks to sustainably manage natural resources, extend product lifecycle and reduce waste. Some of the directions or tools in a circular economy are biomimicry and cradle to cradle. Biomimicry seeks to solve problems by imitating natural processes, while cradle to cradle tends to reduce waste using knowledge obtained from nature. Understanding of nature, its systems and cycles will provide analogies and models for creation of innovative solutions to global problems.

Research subjects of this study are four representative locations in the industrial complex, in the city of Banja Luka, Republic of Srpska, Bosnia and Herzegovina. 16 polycyclic aromatic hydrocarbons (PAHs) (∑16PAHs), humus and pH were determined. The main objective of the paper is to determine the concentration levels, to assess the probable sources of PAHs contamination in soil and groundwater and to determine the ecological risk. The ∑16PAHs in soil (at depths of 30 cm, 100 cm, 200 cm, 300 cm and 400 cm) ranged from 0.99 to 2.24 mg/kg, from 0.34 to 0.46, from 0.24 to 0.32, from 0.13 to 0.27 and from 0.13 to 0.47, with mean values of 1.70 mg/kg, 0.40 mg/kg, 0.28 mg/kg, 0.20 mg/kg and 0.26 mg/kg, respectively. The ∑16PAHs in groundwater ranged from 0.23 to 4.50 mg/m3, with a mean value of 1.42 mg/m3. Surface soil and groundwater are heavily contaminated. All values of ∑PAHs in soil layers were lower in the depths of the soil. Factor analysis indicates three sources of contamination, i.e. principal component (PC) PC1 (pyrogenic), PC2 (petrogenic) and PC3 (biomass), with 52.39%, 26.14% and 8.46% of the total variance, respectively. ∑PAH and PAHs indicate high ecological risk for most PAHs, which decreases with soil depth.

This paper investigates the impact of accidental release of propane gas in surrounding areas consequences of propane gas leak studying the negative effects on both the environment and individuals. Subject of the research is impact of accidental release of propane gas in in business zone “Ramići-Banja Luka”, Banja Luka. The ALOHA software has been used in this paper to modelling of propane release. The modelling was performed for an accidental release of 4,000 kg propane from unsheltered single storied for one hour. For a typical average atmospheric condition in location, this accidental propane release would cause a red zone of 101 metres (AEGL-3=33,000 ppm), orange zone of 159 metres (AEGL-2=17,000 ppm) and yellow zone of 324 metres (AEGL-1=5,500 ppm) to downwind from the source.