By using the PRISMA 2020 flow diagram to illustrate the previously mentioned keywords combination, the ScienceDirect and Web of Science databases were specifically chosen because of their comprehensive coverage of peer-reviewed literature in environmental science, engineering and technology, ensuring access to high-quality, multidisciplinary research relevant to waste management, reverse logistics and Industry 4.0 applications. The authors identified a total of 161 articles, 103 and 58 articles from ScienceDirect and Web of Science databases, respectively. After applying the filters, on each database (language, year, type of document), the number of excluded articles was 29. Then, 8 duplicate articles were excluded, leaving 124 articles to be screened. At this stage, the authors took 4 rounds of reviewing the titles and abstracts, starting with the first author, second author, third author and fourth author and ending with mutual agreement on excluding 74 articles that didn’t provide related information for the study. This led to remaining 47 articles to be included in the narrative summary of the discussion part of this study (Figure 2).

Next section provides qualitative discussion of the final sample of the included papers (47 articles). The authors followed the same procedure of reviewing the full text on 4 rounds, starting with the first author, second author, third author and fourth author and ending with mutual agreement on the exact information to be included in the discussion section and creating the conceptual model.

This theme examines the foundational elements of effective waste collection, including the design and implementation of efficient systems, the development of robust infrastructure, the optimisation of collection networks and the tailored approaches required for managing diverse waste streams (Govindan et al. 2024). Such efforts are crucial for the transition to circular economy principles (CEP) and effective natural resource management, as they maximise the collection of solid waste and direct it towards recycling or remanufacturing facilities, thereby re-entering the production process as raw material (Bui et al. 2024). This approach is vital for environmental, resource and economic sustainability, as it captures the value of waste products, avoids landfills and provides alternative raw materials (Iqbal & Kang 2024). A total of 31 articles relate to this theme, emphasising its multifaceted importance in achieving circularity. The literature highlights a complex interplay of infrastructure, logistical strategies and waste-specific considerations that are essential for efficient material recovery.

The review identifies a variety of established collection methods, including drop-off points (e.g., pharmacies for hazardous waste [Sar & Ghadimi 2022], dedicated e-waste centres and general collection points in stores or public spaces), periodic kerb-side collection, mail-in programmes and point-of-sales take-back programmes (Agnusdei et al. 2022). Door-to-door pick-up services are also discussed (Bijos et al. 2022), while hybrid models that combine formal and informal systems are noted for their potential to optimise efficiency and reach, particularly in developing countries (Mallick et al. 2023). Adequate infrastructure is consistently highlighted as essential, including drop-off locations for consumers, scheduled pick-up services and broader systems for transportation, segregation and treatment (Gallego-Schmid et al. 2024). Innovative solutions, such as pneumatic waste collection systems using underground pipes and vacuum technology, are also presented as smart city alternatives (Kuo & Smith 2018; Yildizbasi et al. 2025).

Optimal reverse logistics network design is another key objective, aiming to minimise costs and environmental impacts while maximising take-back rates. Critical factors influencing design include location, product type, population density, transportation and accessibility (Tolio et al. 2017; Xavier, Ottoni & Lepawsky 2021). For example, traditional systems using a single truck to collect all waste types are less effective, while category-based collection simplifies separation (Nascimento et al. 2019). A consistent trend is the recognition that a one-size-fits-all approach is ineffective, requiring tailored strategies for different waste streams. E-waste management is a prominent focus, with challenges in collection infrastructure, separation and recovery often involving informal channels in many regions (Farooque et al. 2019; Ottoni, Dias & Xavier 2020). Hazardous waste collection through pharmacies highlights the need for specifically designed networks (Sar & Ghadimi 2022). In contrast, the United Kingdom (UK) faces gaps in food waste management, where many councils lack dedicated collection services; proposed solutions include local food waste centres with incentives (Rodrigues et al. 2021).

Technological innovations are frequently noted as enablers of efficiency. Pilot projects using smart bottles have traced leakage and collection outcomes (Ponis et al. 2023), while route optimisation algorithms and automated sensors enhance collection processes (Kolade et al. 2022). Innovative packaging, such as polyethylene terephthalate (PET) trays with RFID and consumer incentives, also supports better sorting and recycling (Rossi & Bianchini 2022). Furthermore, challenges in waste batteries were mentioned, particularly in countries lacking specific waste collection policies, where they are often mixed with general household waste, underscoring the need for separate collection systems (Islam et al. 2025). Industry-led voluntary schemes (e.g., ‘B-cycle’ in Australia) and national deposit refund systems are proposed to enhance collection rates (Islam et al. 2025). Deposit refund systems are especially effective because they offer direct financial incentives that motivate consumers to return end-of-life products, thereby ensuring higher recovery rates and reducing leakage into landfills. Their success depends on broad public engagement, as active citizen participation is essential for returning items and closing material loops within reverse logistics networks. Similar approaches are applied to textile waste, where IoT and robotics support efficient collection and sorting (De Felice et al. 2025; Sarc et al. 2019). Finally, inter-organisational systems, such as footwear collection at designated points, highlight the role of citizen participation in sustaining circular processes (Cafruni Gularte et al. 2024).

The main findings in this theme show that accessible and convenient collection points directly encourage higher consumer participation in waste return programmes, with suggestions that such points should not exceed 0.5 km from consumers to avoid discouraging involvement (Ottoni et al. 2020). Although door-to-door collection is considered the most tedious because of its personnel and time demands, it consistently yields the highest collection efficiency at around 90% and ensures better product condition compared to drop-off systems, which achieve 75% – 80% (Fofou, Jiang & Wang 2021). In contrast, inadequate coverage and accessibility of collection points, especially in rural or remote areas (Mathew et al. 2023), and the persistent low investment in selective collection initiatives are identified as major barriers (Trevisan et al. 2023). The integration of sensors, IoT, AI and cloud computing is reported to enable a transition from fixed-schedule to demand-driven collection, reducing fuel consumption, labour costs and vehicle deployment. Multi-stakeholder collaboration among end-users, councils, retailers, Original Equipment Manufacturers (OEMs), waste management centres and recyclers is also highlighted as essential for reducing costs, minimising environmental impact and improving efficiency (Krstic et al. 2022a; Tolio et al. 2017). At the same time, the informal waste collection sector remains crucial in many developing countries; yet, its informality hampers data tracking and advanced material recovery, making formalisation and inclusion important for enhancing circular practices (Fatimah et al. 2024).

Conflicting issues also emerge in waste collection design. Mallick et al. (2023) note that centralised drop-off points may reduce transportation costs for the overall system but are less convenient for consumers compared to direct pick-up services. In some cases, the frequency of waste collection can even discourage sorting and recycling, showing that more collection is not always better (Gallego-Schmid et al. 2024). Locally organised collection projects, managed by actors who generate, collect or separate waste, can sometimes achieve results beyond what traditional systems deliver, but these initiatives often lack permanence because of limited coordination and commitment from governments and enterprises (Giglio et al. 2024).

Overall, the evidence provides a comprehensive overview of the complexities and recent advances in waste collection systems and waste stream management. The literature draws on diverse geographical contexts and waste types, strengthening the generalisability of the findings. The inclusion of real-world examples, pilot projects and technological applications also enhances practical relevance. Nonetheless, despite the recognition of potential benefits, detailed empirical evidence on long-term impacts, cost-effectiveness and scalability across varied socio-economic contexts remains limited. Many studies rely on conceptual frameworks or pilot initiatives rather than large-scale, sustained implementations.

This theme explores the impact of Industry 4.0 technologies on transforming waste collection within reverse logistics and the circular economy. Information and communication technology (ICT) is identified as a critical success factor, fostering advanced techniques for urban waste collection and processing (Fatimah et al. 2024). By integrating data collection and analysis across supply networks, these technologies enable companies to better understand customer preferences and capture value from waste streams (Julianelli et al. 2020). Smart Waste Management Systems reinforced by information technology (IT) tools and IoT facilities are considered especially crucial for developing and less-developed countries, where such systems are often lacking (Ranjbari et al. 2021). The integration of IoT, AI, augmented reality (AR) or virtual reality (VR), robotics and Blockchain is increasingly seen as essential for achieving circular transitions in different sectors, including textiles (De Felice et al. 2025). Altogether, 31 articles emphasise the role of technological advancements and digitalisation, showing a clear shift towards automated, data-driven and interconnected waste management systems.

Sensors and smart bins are among the most frequently discussed applications. These systems monitor fill levels, temperature and waste classification (Franchina et al. 2021), providing real-time data to optimise collection schedules and routes (Mallick et al. 2023). Advanced smart bins, such as Bigbelly, combine solar-powered compaction, Wi-Fi connectivity and AI sorting (Kerdlap et al. 2019). Other manufacturers, including ‘Green Creative’ and ‘Bin-e’, have integrated material detection sensors and AI for improved waste separation (Sarc et al. 2019). In parallel, IoT connects sensors, bins, vehicles and platforms to enable real-time monitoring (Farooque et al. 2019), supports demand-driven collection (Krstić et al., 2022a) and facilitates material traceability, often together with RFID systems (Govindan et al. 2024; Rossi & Bianchini 2022). Tracking projects such as TRACKPLAST reveal infrastructure gaps and collection inefficiencies in different contexts, highlighting risks of marine leakage (Ponis et al. 2023), while Long Range Radio (LoRa)-based solutions trace packaging waste pathways and accumulation zones (Plakas et al. 2020).

Artificial intelligence is applied for decision-making in routing, logistics design and waste classification (Ciano et al. 2025; Krstić et al. 2022c). Machine learning models provide insights into waste volume and composition, supporting planning and control of municipal solid waste collection and recycling (Bijos et al. 2022). Cloud computing is also important, enabling real-time management of waste types and collection sites while reducing hardware requirements (Nascimento et al. 2019). Blockchain contributes to traceability through digital badges and smart contracts that regulate collection by time, type and volume (Jiang et al. 2023; Krstić et al. 2022c). Together, these technologies support route optimisation, reducing unnecessary trips, fuel use and labour costs (Kerdlap et al. 2019; Kolade et al. 2022).

Robotics and automation expand these opportunities. Projects like DustBot in Europe and ROARy in Sweden tested autonomous robots for waste collection and transport, supported by drones for bin detection (Sarc et al. 2019; Krstić et al. 2022c). Automated guided vehicles and electric autonomous vehicles have also been proposed for sensitive applications such as healthcare waste, reducing risks of contamination (Govindan et al. 2024). Digital platforms and mobile applications further improve efficiency by connecting consumers with collectors, optimising routes and providing recycling information (Mallick et al. 2023; Nascimento et al. 2019).

At the system level, advanced infrastructures such as pneumatic waste collection networks offer smart city alternatives to door-to-door services (Kuo & Smith 2018; Yildizbasi et al. 2025). Deposit refund systems (DRS) also feature prominently, using reverse vending machines and small financial incentives to rapidly increase recycling rates. Deposit refund systems require supply-chain integration through take-back programmes and have shown benefits for resource conservation and environmental sustainability (Zorpas 2024).

Despite strong enthusiasm for these innovations, studies acknowledge limitations. Sole reliance on infrastructure and logistics is insufficient without strong information management systems and improved recycling facilities (Mathew et al. 2023). Moreover, widespread application of Industry 4.0 does not automatically guarantee the most effective outcomes, as costs and stakeholder compromises must also be considered (Krstić et al. 2022b). The coexistence of formal and informal waste collection further complicates integration, particularly in developing countries, where informality obstructs tracking and data systems (Bijos et al. 2022). Resistance to adopting new technologies also stems from limited awareness of their benefits among collectors and recyclers (Gaur et al. 2025).

Overall, the reviewed articles strongly support the transformative potential of digitalisation in waste collection, with robust evidence from real-world projects such as TRACKPLAST, DustBot, ROARy and Bigbelly. However, important gaps remain: empirical data on long-term impacts, cost-effectiveness, and scalability is limited, with most studies relying on pilot projects or conceptual frameworks. Infrastructure deficiencies and informality in waste sectors are not deeply addressed, restricting implementation in resource-constrained contexts (Trevisan et al. 2023). While consumer participation is recognised as critical, its relationship with technology adoption requires further investigation (Mallick et al. 2023). There is also a need to assess the environmental impacts of the technologies themselves within circular economy models (Ciano et al. 2025). Finally, the lack of consistent waste data highlights the need for predictive tools and standardised collection protocols (Afshari, Gurtu & Jaber 2024:4). A more advanced and inclusive approach to data-driven collection would significantly reduce the barriers faced in sorting and recovering end-of-life products (Fofou et al. 2021).

This theme underscores the irreplaceable role of various stakeholders, including consumers, informal sectors, local authorities, industry and producers, in the successful implementation and scaling of waste collection initiatives. Effective engagement, coupled with robust public participation, is not merely a supplementary aspect but a fundamental driver for achieving efficient material recovery and fostering a truly circular economy. It ensures proper waste segregation, increases return rates and facilitates the integration of diverse collection channels (Islam et al. 2025). The waste sector, often dealing with valuable resources, also necessitates stakeholder engagement to mitigate risks such as crime and ensure transparent management systems (D’Adamo et al. 2022).

A total of 20 articles emphasise the critical importance of stakeholder engagement and public participation in waste collection for reverse logistics and the circular economy. The literature consistently highlights that human behaviour (Ponis et al. 2023), collaboration (Islam et al. 2025) and incentive structures (Iqbal & Kang 2024) are as crucial as technological and policy frameworks for effective waste collection (Darzi 2025). Consumer involvement is consistently identified as critical for efficient waste volume management, ensuring proper waste segregation and disposal and actively returning items to designated collection points (Cafruni Gularte et al. 2024). The convenience and accessibility of collection methods are key drivers for encouraging higher participation rates. For that, campaigns are vital for improving collection rates by informing citizens about collection points, accepted waste types and proper recycling practices (Islam et al. 2025). Conversely, a lack of consumer awareness regarding disposal methods or the benefits of waste management is frequently cited as a significant challenge (Xavier et al. 2021). Also, financial incentives play a substantial role in encouraging consumer returns. Deposit refund systems for items like batteries or PET bottles, or direct fees paid to consumers for returning packaging, have demonstrated profound impacts on increasing recycling rates (Zorpas 2024). Paying consumers and retailers for returning expired food items also proves effective (Iqbal & Kang 2024).

The literature emphasises that cooperation among diverse independent stakeholders, including end users, local councils, retailers, OEMs, waste management centres and recyclers, is imperative to reduce costs, minimise environmental footprint and increase collection efficiency (Tolio et al. 2017). This collective approach involves frameworks such as collective work among city halls, malls for installing e-waste collection points and partnerships with warehouse owners to operate cooperatives (Giglio et al. 2024).

In many developing countries, informal collectors handle the majority of e-waste and municipal solid waste, providing a crucial service. However, their informality can pose challenges for data tracking and limit the adoption of advanced material recovery technologies (Trevisan et al. 2023). Government intervention is deemed necessary to regulate and provide guidelines for this sector, and their formalisation and inclusion are crucial for enhancing circular practices and bridging collection gaps (Islam et al. 2025). Here comes the role of the EPR schemes, which shift the physical or financial responsibility for end-of-life products to producers originally handled by governments and municipalities. This scheme considered as a key policy mechanism, necessitates producer commitment and collaboration with other stakeholders for effective take-back systems (Gaur et al. 2025).

The ‘B-cycle’ scheme for battery collection in Australia is an industry-led voluntary scheme for waste batteries which operates a national collection network with over 5200 drop-off points and conducts ‘public awareness campaigns focused on battery safety and proper disposal practices’, such as ‘Never Bin Your Batteries’. Consumer preferences for collection points (e.g., supermarkets for batteries) are studied using survey. The results show that the success of collection systems relies heavily on citizens actively contributing and being adequately educated on proper practices (Islam et al. 2025). Also, the TRACKPLAST pilot project, while primarily technological, also observed how human behaviour (e.g., waste placement) interacts with collection systems (Ponis et al. 2023). In addition, accessible collection methods and proximity to collection points (e.g., not exceeding 0.5 km from consumers) directly encourage higher participation rates (Ottoni et al. 2020).

Deposit refund systems and direct financial incentives significantly increase return rates and recycling. For example, food waste collection centres are established near consumer markets to ease the collection process, and consumers are incentivised to encourage returning the expired food items, with a specific amount of money paid to consumers and retailers (Iqbal & Kang 2024).

Integrating informal collectors into formal systems improves data quality, enhances material recovery and addresses safety concerns. In many Latin American and Caribbean cities, selective collection of the municipal solid waste is carried out by informal collectors that sort and collect recycled materials individually or organised in associations or cooperatives, sometimes with municipal support (Bijos et al. 2022).

The attitude of senior leadership (e.g., in adopting take-back practices) greatly impacts the successful implementation of e-waste management systems (Darzi 2025). E-waste collectors may resist adopting IoT-based tracking systems because of a fear of disruption to their current traditional processes, highlighting a human-factor barrier to technological integration (Gaur et al. 2025).

Canada’s relatively low e-waste collection rate is partly attributed to a complicated collection system divided across geography and e-waste types, making it complex for consumers. The Canadian take-back system faces challenges because of the lack of awareness regarding disposal methods or the unavailability of a drop-off centre, making the system complex for consumers (Xavier et al. 2021).

While local, temporary projects can achieve good collection results, they struggle to establish the long-term interrelation and commitment needed from government and enterprises for permanence. For example, collective work among city halls, malls for installing electronic waste collection points, residential collection companies and partnerships with warehouse owners to operate cooperatives is highlighted as a solution for e-waste collection (Giglio et al. 2024).

The evidence within this theme is robust in highlighting the critical role of human factors and collaboration. The consistent identification of consumer behaviour, public awareness and multi-stakeholder engagement as key drivers or barriers across diverse geographical contexts (Australia, Latin America, UK, Canada) strengthens the generalisability of these findings. The EPR scheme and the DRS provide concrete examples of successful stakeholder integration.

While the importance of awareness, convenience and incentives is well established, the articles generally lack deeper insights into the psychological, cultural or socio-economic nuances that drive or hinder specific consumer behaviours beyond these broad categories. More empirical studies on the effectiveness of different types of educational interventions or incentive designs in varied cultural contexts could be beneficial.

While the need for formalisation of the informal sector is a strong consensus, detailed, actionable strategies for achieving this integration, including specific policy mechanisms, capacity building and financial models that ensure fairness and sustainability for informal workers, are not extensively elaborated in all articles.

The imperative for multi-stakeholder collaboration is clear, but the articles provide limited metrics or methodologies for quantitatively assessing the effectiveness of such collaborations beyond anecdotal success stories or general statements about reduced costs and increased efficiency.

This theme explores the pivotal role of governmental policies, regulatory frameworks and producer responsibility schemes in shaping and driving efficient waste collection for reverse logistics and the circular economy (Farooque et al. 2019; Fatimah et al. 2024). These mechanisms are fundamental to establishing transparent management systems over collected and processed waste, ensuring accountability and incentivising sustainable practices across the supply chain (D’Adamo et al. 2022). Effective policies are crucial for overcoming challenges such as the cost of recovering value from waste and the lack of adequate infrastructure, thereby enabling the deployment of new business models for circularity (Bui et al. 2024). They provide the necessary legal and financial impetus to shift from linear ‘take-make-dispose’ models to circular ones, where waste is recognised as a valuable resource (D’Adamo et al. 2022).

A total of 14 articles emphasise the critical importance of policy frameworks, regulations and producer responsibility in advancing waste collection for circularity yet show a lack of focus in the literature from this angle.

The literature consistently highlights that robust policy interventions are foundational to the success of waste collection initiatives, particularly through the widespread adoption of EPR and DRW.

Extended producer responsibility is identified as a globally adopted policy concept where producers bear physical or financial responsibility for end-of-life (EoL) products. This shifts the burden from municipalities to manufacturers, incentivising eco-design and promoting the collection and recycling of materials, especially hazardous and critical ones (Kuo & Smith 2018). Many countries have adopted product take-back schemes based on the concept of EPR, where producers are physically or financially responsible for the collection of EoL electronics and their recovery. The European Union’s Waste from Electrical and Electronic Equipment (WEEE) Directive mandates EPR, requiring producers to collect 65% of e-waste, exemplified by Germany’s ElektroG Act (Gaur et al. 2025).

Deposit refund systems (are recognised as impactful policy instruments that involve consumers paying a deposit upon purchase and receiving a refund upon returning used items for recycling. These systems have demonstrated profound positive impacts on waste reduction and significantly increased recycling rates over short periods. The DRS have demonstrated profound impacts on waste management, resource conservation and environmental sustainability, to reduce waste and increase recycling rapidly over a short period. For waste batteries, a national deposit refund system is proposed where customers pay a deposit and receive a refund upon return, ensuring high participation. An example from Belgium demonstrated that combining producer responsibility organisations with a deposit system can be cost-effective and significantly improve recycling rates for waste batteries (Islam et al. 2025; Zorpas 2024).

Government intervention is deemed necessary to regulate and provide technical and pollution control guidelines, particularly for the informal waste collection sector. As industries mature, governments are encouraged to gradually reduce direct oversight, allowing e-waste actors to take greater responsibility in accordance with regulatory standards (Darzi 2025).

Mutually consistent policy interventions are crucial for establishing transparent management systems over collected and processed waste, moving towards circular economy models. These policies should be comprehensive, considering factors such as technology levels, subsidies, separate collection systems, existing regulations and political perceptions. The enforcement of producer responsibility regulations is identified as a critical strategy for the recovery and recycling of plastic waste, underscoring the importance of a strong legal framework. Enforcement of producer responsibility regulations to encourage collection of plastic wastes was identified as one of the most critical strategies for the recovery and recycling of plastic solid waste (Detwal et al. 2023; Mwanza, Mbohwa & Telukdarie 2018).

Methods commonly studied in this theme were case studies, such as the EU’s WEEE Directive and Germany’s ElektroG Act, which are also mentioned as examples of EPR mandates (Gaur et al. 2025). Comparative analysis, such as comparisons of e-waste collection systems in countries such as Japan, India and Indonesia, highlights varying levels of formal sector implementation and reliance on informal channels despite regulations (Fatimah et al. 2024). Evidence from policies targeting specific waste streams (e-waste, plastics, and batteries) indicates that regulation must be tailored regulatory needs (Islam et al. 2025; Mwanza et al. 2018).

Major findings are, firstly, EPR is consistently presented as a foundational policy for effective e-waste management and for promoting the collection and recycling of hazardous and critical materials (Farooque et al. 2019). Deposit refund systems are highly effective in rapidly increasing recycling rates and reducing waste, particularly for items like PET bottles and batteries (Zorpas 2024). Secondly, the attitude and strong determination of top executives are critical for the successful implementation of take-back practices and the establishment of effective collection networks (Darzi 2025). Thirdly, a lack of specific policies (e.g., for waste batteries) often leads to improper disposal (e.g., mixing with general household waste), complicating recovery efforts. Inadequate legal conditions and weak dissemination of information are also identified as significant barriers to circular economy deployment (Bui et al. 2024; Mathew et al. 2023).

Although, EPR mandates producer responsibility, manufacturers may struggle to collect e-waste from consumers because of insufficient infrastructural and technological facilities, indicating that policy alone is not enough without adequate support systems (Gaur et al. 2025). Mathew et al. (2023) note that sole dependency on increasing collection points and optimised reverse logistics strategy is not sufficient without a strong information management system and Industry 4.0 assimilation. This suggests that policy, while crucial, must be complemented by other enablers.

The evidence within this theme strongly establishes the indispensable role of policy frameworks and producer responsibility in driving waste collection for a circular economy. The consistent emphasis on EPR and DRS across multiple articles and waste streams (e-waste, plastics, batteries) lends significant robustness to the findings. The use of specific country examples (Germany, Australia, Belgium) provides concrete illustrations of policy implementation and their observed impacts.

However, while policies are described, the articles often lack in-depth analysis of the practical challenges and complexities of policy implementation in diverse socio-economic and political contexts. For instance, the difficulties in enforcing regulations or ensuring compliance, especially in regions with large informal sectors, are noted but not always thoroughly explored with actionable solutions.

While EPR addresses producer financing, the broader financial sustainability required for large-scale investment in waste collection, classification and recycling infrastructure is highlighted as a challenge, but detailed policy mechanisms to ensure this long-term financial viability are not always elaborated.

The necessity of government intervention to regulate and provide guidelines for the informal sector is a consensus, but the specific policy designs that effectively integrate and formalise these workers without disrupting their livelihoods or creating unintended consequences are not deeply detailed.

Most importantly, while some articles provide collection rates (e.g., B-cycle’s 15.3% for batteries), comprehensive metrics for evaluating the overall effectiveness and efficiency of different policy interventions across various waste streams and their long-term socio-economic impacts are not consistently presented.

This theme presents various obstacles that hinder the effective implementation and enhancement of waste collection systems within reverse logistics and circular economy frameworks. Recognising and understanding these barriers is substantial, as they directly impede the transition to CEP, limit material recovery and undermine efforts towards environmental and economic sustainability. Addressing these challenges is not merely about optimising processes but about overcoming fundamental systemic, economic and behavioural impediments that prevent waste from being effectively collected and reintegrated into the value chain.

A total of 12 articles emphasise the significant challenges and barriers to efficient waste collection. The literature reveals a complex web of interconnected challenges, ranging from tangible infrastructural deficits to intangible issues like a lack of awareness and resistance to change.

The various themes identified in this systematic literature review – Industry 4.0 technologies in waste and reverse logistics, waste collection system design and optimisation, policy frameworks and governance mechanisms, stakeholder engagement and consumer participation and challenges and barriers to efficient waste collection – are deeply interconnected and form a dynamic ecosystem crucial for advancing waste collection within reverse logistics and the circular economy. Based on these five themes, this review creates a conceptual framework as illustrated in Figure 3.

At its core, the field is evolving towards a ‘Smart Circularity’ framework, where technological advancements and digitalisation (theme 2) are not merely supportive tools but fundamental enablers. The integration of Industry 4.0 technologies like IoT, AI and Blockchain generates real-time data on waste levels and types, which is then used to dynamically optimise collection routes and schedules within optimised collection systems and waste stream management (theme 1). This data-driven approach shifts collection from rigid, fixed schedules to a more responsive, demand-driven model, leading to significant gains in operational efficiency, reduced costs and improved environmental performance. Technologies like RFID also enhance traceability, ensuring better material flow and quality within these systems.

However, the effectiveness of these advanced systems is heavily reliant on robust policy frameworks, regulations and producer responsibility (theme 4). Policies such as EPR and DRS provide the essential regulatory and financial impetus, mandating producer involvement and incentivising desired behaviours across the supply chain. These policies drive the establishment and improvement of optimised collection systems (theme 1), ensuring the necessary physical infrastructure, such as collection points and logistics networks, is in place. Without adequate policy support and enforcement, even the most sophisticated digital solutions can be hampered, highlighting a direct link to challenges and barriers to efficient waste collection (theme 5).

Crucially, the success of any collection initiative hinges on stakeholder engagement and public participation (theme 3). Accessible and convenient optimised collection systems directly encourage higher consumer involvement, as convenience is a key driver for participation (theme 1). Public awareness campaigns and incentive mechanisms, often driven by policy, are vital for ensuring proper waste segregation and increasing return rates. Furthermore, the significant role of the informal waste collection sector, particularly in developing economies, necessitates their formalisation and strategic inclusion. This integration not only improves their working conditions but also enhances data quality, thereby benefiting technological advancements and overall system efficiency (theme 2). Resistance to adopting new technologies among collectors, however, can emerge as a challenge and barrier to progress (theme 5).

Indeed, resistance to adopting new technologies (theme 5) act as common hindrance across all themes. Inadequate infrastructure, high costs, lack of public awareness, logistical constraints and regulatory gaps create a ‘vicious cycle’ that undermines technological adoption, system optimisation, policy effectiveness and stakeholder participation. For instance, low investment in selective collection (a barrier) leads to underdeveloped sorting systems (a challenge to optimised systems), resulting in lower quality materials and higher recovery costs, further discouraging investment. This interconnectedness means that addressing waste collection challenges requires a holistic, multi-faceted strategy rather than gradual solutions.

Finally, the field has evolved to recognise that a one-size-fits-all approach is ineffective, leading to the need for the development of waste stream specific collection approaches that combine all the previously mentioned themes. Policies, technologies, infrastructure and engagement strategies must be tailored to the unique characteristics of different waste types, such as e-waste, hazardous waste, plastics or batteries, ensuring optimal recovery for each. This specialisation reflects the maturation of the field from generic waste disposal to a nuanced, resource-recovery-focused attempt.

Overall, the evolution of the field is marked by a shift from manual, reactive and disposal-oriented practices to automated, proactive and resource-recovery-focused systems. This transition is driven by the increasing sophistication of technology, the strategic implementation of robust policies, the continuous optimisation of physical and logistical systems, and the recognition of the indispensable role of engaged human behaviour, all while navigating and overcoming persistent systemic barriers.

Notably, 26 articles were pure reviews, 12 were quantitative studies and 9 employed a mixed-methods approach, combining qualitative methods (such as focus groups and interviews) with quantitative analysis. This distribution clearly highlights a significant gap in empirical research and underscores the need for more evidence-based studies to support the theoretical frameworks and technological propositions in the field.