Closed-Loop Supply Chain Design and Environmental Performance of Small and Medium-Sized Manufacturing Enterprises (SMEs) in Nairobi Metropolitan Area, Kenya: A Circular Economy Perspective

The Effect of Lean Manufacturing Practices and Supply Chain Integration on Sustainable Performance: The Mediating Role of Green Supply Chain Management (A Study on the Use of Used Oil)

The coal mining sector in Indonesia faces increasing pressure to balance operational productivity with global sustainability standards, encompassing economic, social, and environmental dimensions. One critical issue requiring strategic intervention is the management of Hazardous and Toxic Waste (B3), particularly the accumulation of used oil generated from heavy equipment maintenance activities. In response to this challenge, PT Bukit Asam Tbk (PTBA) has implemented a circular economy program through its On-Site Plant and Waste Oil Preparation Plant (OSP and WOPP), which converts used oil into a diesel fuel substitute for explosives. However, the success of this initiative depends largely on the organization’s ability to manage internal efficiency and supply chain connectivity to achieve optimal sustainable performance. This study aimed to examine the effects of Lean Manufacturing Practices and Supply Chain Integration on Sustainable Performance, with Green Supply Chain Management (GSCM) as a mediating variable. Lean Manufacturing Practices were implemented to minimize waste in operational processes, while Supply Chain Integration strengthened coordination between internal functions and strategic partners. This synergy was expected to enhance GSCM implementation, increase economic value, minimize environmental impacts, and demonstrate how GSCM mediation connects operational practices with long-term corporate sustainability objectives. A quantitative approach was employed by distributing questionnaires to stakeholders involved in the used oil management supply chain at PTBA. Data were analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM) to examine the significance of relationships among the research variables. The findings are expected to provide a reference for the mining industry in developing integrated waste management strategies while contributing empirical evidence to the literature on green supply chain management in developing economies.

The Influence of Green Supply Chain Management Practices on Sustainability Performance in the Sultanate of Oman Industries: The Mediating Role of Environmental Collaboration

Green supply chain management (GSCM) has become a strategic requirement for industrial firms seeking to reduce environmental harm while improving long-term sustainability performance. Despite growing interest in green procurement, eco-design, green manufacturing, and green distribution, limited empirical evidence explains how these practices are converted into sustainability performance through collaborative environmental action in the Sultanate of Oman. Guided by the Natural Resource-Based View, this study examines the effects of four GSCM practices on environmental collaboration and investigates the mediating role of environmental collaboration in the relationship between GSCM practices and sustainability performance. A quantitative cross-sectional survey was conducted among procurement, manufacturing, logistics, and supply chain professionals working in Omani industries. From 520 questionnaires distributed, 342 valid responses were retained for analysis. The data were analyzed using Smart PLS 4.0 and partial least squares structural equation modelling. The measurement model demonstrated acceptable reliability, convergent validity, and discriminant validity. The structural results show that eco-design, green procurement, green manufacturing, and green distribution have significant positive effects on environmental collaboration. Environmental collaboration, in turn, has a strong positive effect on sustainability performance. The indirect effects also support the mediation of the relationships between the GSCM practices and the sustainability performance, confirming the mediation chain. The results indicated that green practices are not enough; they have to be integrated with the collaboration of suppliers, customers, logistics and other functions within the company to make green practices produce results in terms of performance. The study adds to GSCM and sustainability literature by providing a relational mechanism that determines the contribution of green practices to the industrial sustainability of the Oman context.

Drivers and Barriers of Sustainable Supply Chain Management in the Federal Capital Territory (FCT), Nigeria: A Critical Evaluation

This study critically evaluated the drivers and barriers to Sustainable Supply Chain Management (SSCM) in the Federal Capital Territory (FCT), Nigeria. The research sought to assess the level of SSCM adoption among organizations and identify the key factors influencing its implementation. SSCM integrates environmental, economic, and social considerations into supply chain operations to improve organizational performance, competitiveness, and long-term sustainability. A quantitative research design was employed using a structured questionnaire administered to supply chain professionals, procurement officers, logistics managers, and related personnel from selected public and private organizations in the FCT. A stratified random sampling technique ensured broad sectoral representation, while descriptive and inferential statistical methods, including mean scores, standard deviation, correlation, and regression analysis, were used to analyze the data. The findings indicate that SSCM adoption in the FCT is moderate, with organizations primarily implementing practices such as waste reduction, energy efficiency, and compliance with environmental regulations. The major drivers of SSCM adoption were identified as government regulations, increasing customer environmental awareness, and strong top management commitment. However, implementation is constrained by high adoption costs, inadequate technological infrastructure, limited management support, and weak regulatory enforcement. The study concludes that although awareness of sustainable supply chain practices is increasing among organizations in the FCT, comprehensive implementation remains constrained by financial, institutional, and structural challenges. It recommends strengthening regulatory enforcement, investing in sustainable technologies, enhancing organizational capacity through training, and promoting collaboration among government, businesses, and

Assessing the Need for Environmental Cost Accounting in Plastic Recycling Small and Medium Enterprises: A Case Study of Manado Recycle Hub, Manado City

Plastic recycling Small and Medium Enterprises (SMEs) play a significant role in reducing environmental pollution by recovering and reprocessing plastic waste. However, most SMEs still lack an adequate system for recording environmental costs, limiting their ability to evaluate environmental expenditures and support informed decision-making. This study aims to assess the need for environmental cost accounting in plastic recycling SMEs through a case study of Manado Recycle Hub, Manado City, Indonesia. A descriptive qualitative approach with a case study design was employed. Data were collected through structured interviews consisting of 30 questions, direct field observations, and an analysis of business documents. The data were analyzed using gap analysis to compare existing accounting practices with Green Accounting principles. The findings reveal that environmental expenditures, including water and electricity consumption, waste management, personal protective equipment, and transportation costs, are incurred regularly but are recorded as general operating expenses without specific classification. Although the business owner demonstrates strong awareness of the importance of environmental cost accounting, its implementation is constrained by limited accounting knowledge and the absence of a simple recording system. The identified needs include a Microsoft Excel-based accounting system, separate classification of environmental costs, environmental cost reporting, and a user-friendly recording procedure. These findings provide a foundation for developing a simple and practical environmental cost accounting system tailored to the characteristics and operational needs of plastic recycling SMEs

Integrating green logistics and Industry 4.0 to drive sustainable performance: A circular economy and waste management perspective

In the context of growing environmental concerns and digital transformation, small and medium-sized enterprises (SMEs) in emerging economies face increasing pressure to improve sustainable performance (SP). Green logistics management (GLM) and Industry 4.0 technologies (ID4.0) have emerged as promising solutions. However, previous studies have often examined these dynamics individually and failed to capture the mediation mechanisms particularly circular economy practices (CEP) and waste management (WM) that transform digital and green capabilities into sustainable outcomes. This study aims to develop and empirically test an integrated model that investigates the direct and indirect effects of green logistics management and ID4.0 on SP, with CEP and WM as mediating variables. The model is evaluated using Partial Least Squares Structural Equation Modeling (PLS-SEM) conducted in R. Data were collected from 144 respondents representing manufacturing and logistics SMEs in Vietnam. The findings confirm that GLM positively influences both CEP (β = 0.644) and SP (β = 0.276), while ID4.0 significantly impacts WM (β = 0.575) but has only a modest direct effect on SP (β = 0.126). CEP (β = 0.225) and WM (β = 0.388) both play significant mediating roles, reinforcing their importance in sustainable performance. This study contributes to sustainability research by validating a comprehensive framework that connects digitalization, green logistics, and environmental process integration. For practitioners, the results offer a strategic roadmap for SMEs to enhance SP through the simultaneous adoption of ID4.0 technologies, green logistics practices, and circular economy principles.

Green logistics, technology adoption, environmental practices, and supply chain resilience: evidence from logistics and supply chain firms in Bangladesh