Plastic Pollution and Framework Towards Sustainable Plastic Waste Management in Nigeria: Case Study

Abstract

Plastic pollution and its environmental consequence are on the rise globally. In Nigeria, the proliferation of plastic bottle and sachet water (PBSW) manufacturing companies in various parts of the country has led to an increase in plastic waste generation. Existing studies have identified challenges and the critical need for the adoption of sustainable solutions to mitigate its adverse environmental impact, especially for developing countries. Therefore, the motivation for this study stems from the urgent need for a progressive shift in the studies focused on feasible solutions to the common challenges and strategies for implementation. This study aims to investigate the identified challenges of a lack of awareness and waste management of single-use plastics in Nigeria, towards achieving a circular economy of plastic waste whilst considering its socio-economic context. This study used a mixed method approach combining quantitative and qualitative data through interviews and questionnaires to investigate awareness on the impact of plastic pollution amongst key stakeholders in plastic waste management in the UNN. The potential of introducing a DRS in the sustainable collection of single-use plastic bottle and sachet water waste was also explored. The result reveals the perceived consequence of plastic pollution is short-term, at the level of mesoplastics, physically observed as plastic litter (68.2%), leading to a blockage of canals (65.0%), an excessive rate of flooding (19.1%) and other related issues; effective channels of creating awareness and educating the public on plastic pollution are social media (48.3%), school education (23.3%), mass media (21.7%), and others (6%). An implementation framework for sustainable plastic waste collection was developed from the research findings, adapting the Norwegian Deposit Return Scheme (DRS) to suit the current socio-economic context of the population. Additionally, awareness can be increased through targeted government policies that reward sustainable plastic waste management practices, public awareness campaigns, and the use of social media.

1. Introduction

Over the years, plastic production has continued to rise, leading to a global increase in plastic waste [1]. Given their exceptional qualities such as durability, low cost, and flexibility in manufacturing, plastics are used extensively for single-use packaging products [2,3]; nevertheless there is an urgent need to mitigate any form of its unsustainable use and disposal that leads to environmental pollution [4].

As a result of their affordability and perceived greater quality compared to tap water, sachet and bottled water has widely gained acceptance in Nigeria and most African countries as a source of drinking water [5,6]. Popularly known as “pure water,” sachet water is made up of 500 mL LDPE (Low density polyethylene) plastic bags of drinking water sealed on both ends using an electric heating process [7]. Similarly, portable water packaged in Polyethylene terephthalate (PET) plastic bottles of different volumes, ranging from 750 mL to 1500 mL is known as bottled water.

Ref. [3] reports plastic waste as the third largest component after organic and paper waste in Nigeria, constituting about 20% of the total municipal solid waste [8], with a significant amount comprising of PBSW waste. Owing to its high and growing population of 229.5 million [9], Nigeria is estimated to generate an average of 2.5 million tonnes of plastic waste annually [10,11], have a daily consumption of sachet water of about 60 million [8,12], and produce an average of 200 million PET bottles daily [13].

Previous studies have identified indiscriminate disposal of PBSW waste as a leading factor contributing to plastic pollution in Nigeria [8,14] and becoming a bane for effective waste management in most developing countries in Africa [15].

Approximately one million sales of plastic bottles are recorded per minute globally [16]. By 2050, it is anticipated that the global amount of plastic trash in landfill and/or the environment will amount to almost 12,000 Mt. Although there is still a need for sufficient data regarding the total amount of plastic waste generated in Nigeria, some researchers have attempted to characterize municipal waste in different regions of the country [17] and some universities [18,19,20], reporting an average of 15% to 30% composition of plastic waste.

Ref. [20] reports that 32.36% of the total waste generated in the University of Nigeria, Nsukka campus is made up of polyethene used in packaging sachet water and other similar items, while 9% consists of PET bottles used for potable water and other drinks. Universities can be comparable to small cities, and sustainable campuses can make a major contribution to improving sustainability in their community, mitigating the environmental impact and promoting healthy and sustainable lifestyles on campus and in their host community.

Plastic pollution resulting from the inefficient management of plastic waste [21], has evolved into a global environmental problem due to its adverse effect on public health [22,23] and contribution towards climate change [23], as a result of the carbon emissions associated with its Life Cycle Assessment (LCA). The UN’s sustainable development goals (SDGs) outlines strategies to achieve plastic waste circularity and its anticipated future outcomes globally [24]. However, more work still needs to be done by the relevant stakeholders in developing nations like Nigeria where open dumping and open burning is commonly practised [25,26], following the undesirable linear pathway of make use and dispose for plastic waste.

In alignment with the ambitious United Nations Environment Assembly’s (UNEA) resolution to end plastic pollution, Ref. [27] identifies five key intervention areas: (I) Addressing the plastic waste with regulations, (II) Collective responsibilities in plastic reduction, (III) Concerns in waste management and collection, (IV) Enhancing collection efforts through education, and (V) The importance of technology in ending plastic pollution. The principles of ISWM and PPH, illustrated in Figure 1, emphasizes waste reduction through material reduction, reuse, recycling, and recovery (3R), which are the most preferred options for sustainable waste management.

Over time, significant improvement has been achieved in source reduction with the production of lightweight plastic packaging materials due to improvements in technology and manufacturing. The weight of a 50cl water bottle has decreased by half since the early 2000s, although the resource or weight reduction of plastics might also have an impact on its recyclability [28] and the perceived value in the informal plastic recycling sector by waste pickers.

This study proposes the adoption of the Norwegian Deposit Return Scheme (DRS) as a sustainable framework for plastic waste collection to significantly reduce the littering of PBSW waste, promote the effective management of plastic waste, and increase the prospects of achieving a circular economy of plastics in Nigeria. This research also seeks to investigate the willingness of consumers and the relevant stakeholders in the PBSW industry to accept and participate in the DRS.

The DRS is practised by developed nations like Germany, the US, Sweden, Norway, and some other European countries. It has proven to be an effective system for plastic waste collection, motivating consumers to return the packaging waste for water and other beverages at designated points or vending machines. In 2016, the government of Lithuania, after implementing the DRS, saw an increase in the collection rates from 32% to 92% in just two years [29].

Plastic pollution is gaining a lot of attention globally from different stakeholders including international organizations, researchers, manufacturers, government, NGOs, and the entire public; a lot of studies have identified problems associated with plastic pollution and suggested possible solutions to the environmental menace. Indiscriminate disposal, a lack of awareness, and insufficient infrastructure for plastic waste management, starting with collection, transportation, etc., are predominant challenges faced by developing nations, leading to a high rate of plastic leakage into the environment. Notably, a lack of awareness among consumers and key stakeholders in plastic waste management is one of the most consistent problems identified from numerous studies as the enablers of plastic pollution. Therefore, the question becomes “how can the problem of awareness among consumers and key stakeholders in plastic waste management be tackled wholistically”, to successfully implement the prospects of a circular economy in practice for developing nations to reduce the alarming rate of plastic leakage into the environment.

However, there is a research gap in understanding the awareness level of consumers and key stakeholders in plastic waste management of the environmental impact of plastic pollution, in order to identify loop holes Therefore, this research aims to bridge this gap by investigating the awareness on the environmental impact of plastic pollution of consumers and of key stakeholders in the PBSW industry, as well as their willingness to accept and participate in the Norwegian DRS as a sustainable framework for plastic waste collection in order to prevent its leakage into the environment using the University of Nigeria, Nsukka campus as a case study. Although Norway is a developed country, Nigeria is still a developing country with limitations in terms of waste management infrastructures. However, recent initiatives and partnership by the Nigerian government reveals the similarities of the consciousness of a shared responsibility to combat global plastic pollution and contribute towards the circular economy of plastics. According to [30], innovative initiatives, such as the deployment of locally designed self-service RVMs (Reverse Vending Machine) for plastic waste, adapted to interact in the three major Nigerian languages, like the Norwegian model, have been installed in Abuja.

The objectives of this study are as follows: (1) to investigate the awareness on the environmental impact of plastic pollution of consumers and the relevant stakeholders in the PBSW industry; (2) to determine the effective channels of increasing awareness and educating the public on the impact of plastic pollution and the benefits of sustainable plastic waste management practices in Nigeria; (3) to investigate the consumers and stakeholders’ willingness to embrace and participate in the Norwegian DRS, in a step towards reducing plastic waste management issues in Nigeria; (4) to develop a framework for plastic waste collection through adaptations of the Norwegian DRS to suit the socio-economic context and the infrastructures in Nigeria; (5) to identify the key drivers for sustainable plastic waste management in Nigeria amongst the PBSW stakeholders.

2. Conceptual Framework

2.1. Current State of Plastic Waste Management in Nigeria

The relatively low cost of the manufacturing of plastic (PET) bottles and sachets for packaging water, a lack of pipe-borne water, and the population growth in a developing country like Nigeria has given rise to a high demand for plastic bottles and sachets for packaging drinking water, thereby leading to a corresponding high volume of plastic waste and pollution in the environment.

Currently, the available infrastructure in the UNN for waste disposal does not have colour-coded bins to separate waste into categories such as plastics, organics, and general waste, leading to the disposal of PBSW waste (including other recyclable waste) in the general waste bins; thereby incurring additional costs for the sorting, cleaning, and separation of the different categories of plastics due to their mixture with food and other organic waste by those in the recycling value chain.

Also, it is common practice for the consumers of packaged water and other beverages to drop the empty containers on the floor at the point of consumption, indiscriminately thereby littering the environment, which results in devastating flooding due to blocked drains in rainy seasons [8].

2.2. Awareness on Environmental Impact of Plastic Pollution

A significant number of studies have highlighted the problems [4,23,31,32,33,34] the policy needs [35,36], and the opportunities [34,37,38] in plastic waste management.

Solutions to these problems have also been identified by different researchers such as; championing awareness campaigns by government and non-governmental organizations, a global plastic treaty to reduce plastic production, education/outreach by health practitioners to their patients, more scientific evidence from research to provide reliable information for policy makers, manufacturers, and consumers, etc. [22,33,35,36,39].

The central theme of the solutions presented from these studies suggest that there is need for an increased awareness of the consumers and other stakeholders (government, manufacturers, retailers, etc.) of the persistence of plastics and its negative impact on the environment. Ref. [40] identified a low level of awareness as a key enabler of the increasing rate of plastic pollution globally and its undesirable consequences observed in Nigeria.

A search from the past literature revealed a few studies that have attempted to investigate an awareness of plastic pollution. Ref. [41] investigated the awareness level and knowledge of solid waste management of secondary school students in Nigeria. Ref. [42] examined topics on plastic pollution in the primary and secondary school curriculum in South Africa, Ref. [43] evaluated the public’s perception of marine plastic pollution and the recent EU Directive on SUPs in Greek, and the assessment of students’ knowledge of/attitudes towards plastic and microplastic contamination was studied by [44] in India. The result of the search revealed the gap in studies investigating the awareness of consumers and relevant stakeholders in plastic waste management of the impact of plastic pollution on the environment and public health. Therefore, this study aims to investigate the awareness of consumers and relevant stakeholders on the impact of plastic pollution in Nigeria, using the PBSW as a case study. This study also attempts to assess the participants level of understanding on some environmental concepts such as plastic pollution and the presence of microplastics in the ecosystem and the circular economy and climate change in relation to sustainable development goals. Consequently, RQ1 and RQ2 were derived; thus,

RQ1: What is the consumer’s and key stakeholder’s level of awareness of the impact of plastic pollution on the environment and public health?

RQ2: What are the most effective channels of educating the public on sustainable waste management practices and the impact of plastic pollution?

The findings from this research will serve as a benchmark for future research on the investigation of the awareness of relevant stakeholders in plastic waste management. It will also provide the government and relevant stakeholders, such as NGOs, international environmental organizations, etc., with necessary insights on the different levels and intensity of the awareness campaigns to be carried out on plastic waste thinking, the impact of plastic pollution, and the environmental problems arising from the improper disposal of plastic waste, suitable for the current level of awareness of the citizens in the country.

2.3. Plastic Waste Collection

Ref. [35] reveals that uncollected waste accounts for 75% of the ocean plastic debris that comes from land-based sources. Figure 1 suggests that in the waste systems aspect for integrated sustainable waste management, the next most important aspect after waste generation to attain sustainable plastic waste management is “waste collection”.

The waste system element of integrated sustainable waste management recognizes that “waste collection” is the next most important aspect after waste generation. Plastics, depending on their size, are categorized as macro, meso, and microplastics [45,46]; similarly, the persistence of plastic waste in the environment, resulting from their non-biodegradability, disintegrates over time into these sizes in the environment. According to [46], the most widely used classification of plastics by size defines macroplastics as larger than 25 mm and the easiest to clean up from the environment, while mesoplastics are made up of sizes between 5 mm and 25 mm, and macroplastics of sizes less than 5 mm, which typically escape clean-up efforts [45,47]. Furthermore, Ref. [40] identified that plastic waste collection is a significant bottle neck to sustainable plastic waste management in Nigeria; the study also recommends that an intervention for plastic sorting and collection is established. Therefore, it is important to focus on establishing a resilient framework for effective municipal plastic waste collection to enhance the possibilities of subsequent reuse, recycling, and resource recovery to institute the sustainable management of plastic waste in Nigeria. Additionally, this suggests that the first step in mitigating plastic pollution and establishing a sustainable PWM system in Nigeria in line with the principles of ISWM and PPH is to create an efficient plastic waste collection system that is simple and acceptable for all, including consumers and the relevant stakeholders in the supply chain of plastic waste management. Plastic waste separation at the point of use and plastic waste collection are fundamental towards achieving a circular economy of plastic packaging waste [38].

Figure 2 depicts the essential role an effective plastic waste collection system plays in the prevention of plastic pollution, which is a requisite to achieving plastic waste reuse, recycling, and recovery in the PPH.

This study focuses on the adoption of the Norwegian DRS as a starting point to solve the multi-faceted problems of plastic waste management in Nigeria by establishing a sustainable plastic waste collection system. The scheme has been successful in Norway and some developed countries in combatting plastic waste littering as well as the improved collection and recycling rates of post-consumer plastic packaging waste. This research intends to explore the potential of adapting the experiences and lessons learnt from the Norwegian DRS to suit the cultural and socio-economic landscape in Nigeria, by combining the principles of ISWM and Pollution Prevention Hierarchy (PPH) of the country. This scheme can be further extended to other developing countries in the region, which are experiencing similar challenges to Nigeria.

2.4. Norwegian Deposit Return Scheme (DRS)

The main goal of the Norwegian DRS is to encourage recycling while also providing incentives for people to dispose of their waste properly. The introduction and implementation of the DRS in Nigeria will also contribute towards increasing and upgrading the awareness level of consumers and the other relevant stakeholders in achieving a sustainable plastic waste management system in Nigeria. This can help in changing the consumer’s thinking on plastic waste, where plastic bottle and sachet waste is no longer perceived to be valueless material, but rather regarded as valuable material that can be exchanged for money or used in purchasing other items from the participating stores. The DRS was implemented in Norway in 1998 and has now been established in different countries; it has also been recently adopted by Scotland and England for subsequent implementation once the necessary infrastructures and policies have been put in place.

According to [13], the critical success factors of the Norwegian DRS a result of transparency in operations by Infinitum, leading to the ownership of the scheme by Norwegians. Infinitum, the company in charge of the DRS in Norway is a private non-profit company owned by manufacturers, retailers, and non-governmental organizations. It ensures that its operation and financial report is transparent and available to the public. Norwegians trust the system and have come to the point of ownership of the scheme, which is responsible for the high percentage of returned plastic bottles with a return rate of 92.3% in 2021. Also, Infinitum usually runs online surveys to get feedback from citizens on the performance of the system, which has helped to improve the scheme.

Infinitum-approved labelling and production in accordance with the material packaging specification is required for all containers. This means that all the plastics from different manufacturers under the DRS are pre-registered before commencing business operation.

There is a standardized specification for all the plastic bottles and their covers in the scheme which implies that the physical and chemical properties of the plastic bottle must be tested and approved before it is enrolled into the scheme. Consequently, the time spent in sorting before recycling is optimized.

Predominantly, the laws and policies guiding the Norwegian DRS are very flexible and are regularly adapted to suit the socio-economic changes that may occur in the country. For example, during inflation, the prices of the deposit were reviewed upward to encourage higher return rates, with about 1% of the littering of plastic waste recorded in Norway [48]. Therefore, to mitigate the littering of plastic waste and establish sustainable plastic waste management, Ref. [40] emphasized the adoption of policies and legal instruments such as market-based incentives to induce pro-environmental behaviours towards plastic waste management in Nigeria. It is expected that this will facilitate the establishment of a framework for plastic waste collection in the country. Following on from the solutions gathered from various studies by [39,49,50] one effective way to reduce plastic pollution in Nigeria is the adoption of a market-based policy that can induce pro-environmental behaviours. Notably, the population of Nigeria is higher than that of Norway, although this difference in population can influence the implementation logistics of the DRS. However, the core principles and foundational elements for a DRS such as EPR, financial incentives for consumers, and a centralized administrative system are applicable regardless of the population size. For example, Germany, with a far higher population than Norway, operates the DRS with a 98% return rate. Other key objectives of this study is to investigate possible adaptations to the Norwegian DRS to suit the socio-economic situation of Nigeria and develop a framework for PBSW waste collection. This study aims to answer the following additional questions.

RQ3: Can the lessons learnt, or experience gained by the Norwegian DRS, be adapted and implemented in the Nigerian context?

RQ4: Can the good practices responsible for the successful implementation and ownership of the Norwegian DRS be modified and applied towards addressing / improving plastic waste management problems in Nigeria?

3. Materials and Methods

3.1. Study Area

This study was conducted in the University of Nigeria Nsukka (UNN), located in the South-East region of Nigeria with latitude: 6°51′33.41″ and longitude: 7°23′52.51″. This study was carried out on the main campus located in Nsukka, consisting of nine faculties and sixty-two departments [20].

3.2. Study Design

3.2.1. Sampling Technique and Study Participants

The study design used for this research is a mixed method combining both quantitative and qualitative data from respondents within the campus community and stakeholders in the PBSW waste management in the UNN and the state. Combining qualitative and quantitative methods in waste management research helps to reduce study biases and has the added benefit of raising community participants’ awareness of the issue. This study also employed simple random and purposive sampling methods in the distribution of the online questionnaires to the respondents while the selection of participants for the semi-structured interview was carried out using the purposive sampling method.

A semi-structured interview was conducted with a total of six people representing four key stakeholder groups in plastic waste management in the study area: two senior managers of the university-owned PBSW manufacturing company on campus, two retailers of PBSW on campus, the manager of a privately owned waste management company, and one senior manager in the state government waste management authority (ESWAMA) which is the body responsible for municipal solid waste management in the state.

Table 1. The distribution of the participants and the interviewed stakeholders in the survey.

Participants	Students	Staff	Others	Total
Sample Number	91	14	16	121
Percentage Distribution (%)	75.2	11.6	13.2	100
Stakeholder Groups.			Number of persons.	Assigned code Number.
Manufacturer			2	P1, P3
Retailer			2	P2,P6
Government Waste Management Authority			1	P4
Private Waste Management Company			1	P5

shows the distribution of the participants in the survey, as well as the stakeholders involved in PBSW, the interviewed stakeholders, and their assigned codes.

3.2.2. Survey Questions and Data Collection

The questionnaire was distributed and collected using an online form while in-depth semi-structured interviews were conducted with the stakeholders virtually. The survey and interview questions were derived from published scholarly literatures on the challenges of plastic waste management in Nigeria and adapted slightly to capture the stakeholders’ contribution in achieving an effective and acceptable plastic waste collection system. Figure 3 shows the distribution of the respondents to the online survey.

The interview was recorded using an audio recorder after receiving consent from the participants. The participants were assured of the confidentiality and anonymity of their personal data to ensure openness from them. A copy of the interview questions was sent to each of them before the scheduled time to give them enough time to reflect on their responses to draw insights from their wealth of experience in plastic waste management. At the beginning of the interviews, all the participants were asked loosening-up or icebreaker questions, e.g., about the general attitude towards PBSW waste, to make them feel comfortable throughout the discussions. The interviews were conducted in English and Igbo (the native language of the study area) language, which allowed the participants to communicate effectively in the way that seemed best to them in conveying their points clearly. Figure 4 captures the different waste disposal points within the university.

4. Results and Discussion

The results of the survey show the different sections of the questionnaire, capturing the response for each category of questions investigated in this study (Supplementary Materials). A total of 121 responses were completed, consisting of students (75.2%) from all academic levels, staff (11.6%), and others (13.2%). Others represent non-academic individuals that make up the university community, including workers in commercial buildings within the campus and family members of residents in the staff quarters. Awareness has both psychological and behavioural aspects as it relates to human beings. The Theory of Planned Behaviour has been applied to determine the intention, the attitude, and the behavioural patterns of human beings, as it relates to pro-environmental behaviours like littering. In developing countries like Nigeria, to fully understand the sociological and behavioural influence of the practice of littering, it is pertinent to investigate the stakeholders’ awareness on the impact of plastic pollution to determine their level of awareness of its consequence on the environment and public health.

RQ1: Consumers and key stakeholders’ level of awareness of the impact of plastic pollution on the environment and public health?

The results of this study reveal that the awareness of consumers and the stakeholders interviewed of the impact of plastic pollution is majorly at the level of macroplastics, where the direct impact caused by improperly disposed-of plastic bottles and sachet packaging for drinking water on the environment is short-term (immediate and visible).

Consumers reported their understanding of the impact of plastic pollution on the environment in the following areas: plastic litter (68.2%), blockage of canal and waterways (65%), and an excessive rate of flooding (19.1%), and other responses are sore eyesight, bad aesthetics, and illness. The interviewed stakeholders also shared the same view when highlighting other observed impacts such as soil pollution, erosion, degeneration of roads and buildings due to flooding, and the eyesore caused by littering and the improper disposal of plastic waste on the environment. Figure 5 illustrates the four levels of awareness of the different categories of plastic waste that exist in the environment.

The senior manager of the state waste management authority interviewed replied, “…I don’t know what to do with the pure water sachet….” (P4, Govt. Waste Official). In his opinion, the littered plastic bottle waste is still perceived to be valuable and is picked up by waste scavengers and sold to plastic manufacturing companies, but the waste from the sachet water is perceived to be valueless, thereby accumulating in the environment for a long time, causing havoc in the environment. Although, one of the stakeholders representing the manufacturers group during the interviews shared that the plastic water bottle and sachet waste is used regularly by people in the rural communities within Nsukka as fuel for burning firewood for cooking “…Due to their literacy they use it to open fire…” (P1, Manufacturer). It is perceived that this might be one of the contributing factors to the prevalence of health problems in society. The reason for this low level of knowledge about microplastics in Nigeria might be due to the dearth of research on the prevalence of microplastics in different habitats in Nigeria such as water, air, land, etc., as well as sufficient studies on the impact of microplastics on public health and the ecosystem in Nigeria.

The current awareness level of participants (consumers and interviewed stakeholders) in this study of the negative impacts of plastic pollution on the environment is still at the base level. However, it is sufficient in influencing positive attitudes and pro-environmental behaviours in handling plastic waste because the problematic chain of issues caused by plastic pollution starts with macroplastics on land, then subsequently leaks into the ocean and other aspects of the ecosystem [44]. About 80% of the respondents are aware that plastic pollution is a global environmental problem; they also have an idea of the following environmental concepts such as circular economy (12.2%), sustainability (36.5%), climate change (80%), carbon emissions (45.2%), and microplastics (9.6%), with none of the above (7.8%). It was also observed that the interviewed stakeholders are not aware of the meaning of microplastics, sustainable development, and circular economy. This follows the observation from a recent study carried out in the southeastern region of Nigeria, where some consumers perceived that the manufacturers’ contribution to society by providing the public with access to portable water is enough; hence consumers should take responsibility for the plastic waste [8]. Some of the stakeholders interviewed also demonstrated ample knowledge on plastic pollution contributing to climate change, but only at the end-of-life stage through the practice of open burning of plastic waste which emits GHGs. However, they are not aware of emissions at different stages of their life cycle from the cradle, i.e., from the extraction of raw materials, manufacturing, transportation, etc. [40] agrees that increased return rates of plastic waste by consumers have been beneficial in mitigating the problem of littering in both developed and developing countries with a deposit return system in place. Moreover, the study by [51] to determine factors that influence consumers’ behaviour to return plastic waste concluded that the “awareness consequence” is one of the three main factors that significantly influence the return/recycling intention of consumers in a developing country, the two other factors being subjective norms, and convenience.

These studies suggest that if the consumers and relevant stakeholder’s “awareness consequence” on the impact of plastic pollution and the benefits of returning/recycling plastic waste increases, the littering of plastic waste in Nigeria will be considerably reduced. This can be achieved through the design of appropriate educational materials and awareness programmes which incorporate awareness of the prevalence and effect of macroplastics, mesoplastics, microplastics, and nano-plastics on the environment, having identified the current level of awareness of consumers and other stakeholders as revealed in this study. Ref. [52] argues that public awareness, rather than being just an end goal, serves as the foundation and key driver for meaningful environmental actions. This implies that there is a need to complement public awareness with the development of adequate infrastructures and partnerships to facilitate the transition from awareness into a series of progressive actions, leading towards establishing a sustainable collection system of plastic waste and ultimately circular economy targets.

Therefore, to ensure that increased awareness leads to tangible outcomes, it is imperative to invest in and expand recycling infrastructures, integrate informal waste collectors into the formal sector, have strong collaboration amongst stakeholders, etc. [53]. Although the current infrastructure for waste collection in Nigeria is inadequate [54], recent initiatives like the installation of Reverse Vending Machines (RVMs) in Abuja represent progress, but their current scale is insufficient to handle the country’s vast plastic waste output [30].

RQ2: What are the effective channels for educating the public on the impact of plastic pollution?

The first step in creating awareness might be through the reinforcement of already existing environmental policies that prohibit littering and clearly stipulate the responsibilities of all stakeholders involved in plastic waste management by the government. A total of 96.7% of the respondents affirm that increased awareness on the dangers of plastic pollution will help to reduce littering in the environment. Although, Ref. [36] argues that there may not be a single solution to the problem of littering, and the need for a binding regulation to effectively limit pollution caused by littering. In Nigeria, NESREA is the agency of the Federal Ministry of Environment, responsible for enforcing all environmental laws, including those related to waste management. The agency established the National Environmental (Sanitation and Wastes Control) Regulations 2009, which applies to issues of environmental sanitation and all categories of waste including plastic waste. According to Ref. [49], Section 71 of this regulation makes it a criminal offence for any person to litter the environment and dispose of waste in an unsanitary manner and prescribes a fine of 20,000 NGN or six-months imprisonment or both. The results of this study reveal that the most effective channel of creating public awareness is social media 48.3%, followed by formal school education (23.3%), mass media (21.7%), and others (6%). One might argue that this result might be due to the demographics of the population, which majorly comprise young university students with easy access to the internet with their personal computers, mobile phones, and/or various digital devices.

However, Ref. [55] confirms that pro-environmental social media campaigns significantly influenced the reduction of single-use plastics, increased recycling efforts, and the promotion of eco-friendly alternatives in Thailand. Involving social influencers and community leaders in advocating for the 3R (Reduce, Reuse, Recycle) principles can further encourage the transition from a linear to a circular plastic economy. Additionally, integrating environmental education into school curricula has been shown to enhance the students’ environmental knowledge and foster pro-environmental behaviours, thereby contributing to broader sustainability goals [56]. Notably, the government is perceived to have a higher responsibility towards educating the public and creating more awareness on the duties and obligations of relevant stakeholders towards achieving sustainable plastic waste management. However, the task of educating the public on the impact of plastic pollution on the environment should not just be for the government alone; key stakeholders and other NGOs should also be involved in the creation of awareness on the impact of plastic pollution on the ecosystem. Academic and other educational institutions need to collaborate with the government to educate students at all levels about pro-environmental practices such as the separation and disposal of plastic waste in the appropriate bins for recycling. The government needs to strengthen the plastic waste management system by creating new laws targeted at single-use plastics and ensure strict compliance at all levels through the enforcement of penalties and punishment of defaulters. Infrastructural improvements such as providing separate wastebins for sorting plastics at the point of disposal can enhance the successful implementation of these regulations; the positive impact and possible future benefits of consumers and other stakeholders’ participation in ensuring a safe environment for everyone should be part of the public awareness campaigns. Predominantly, using social media, various mass media channels, and incorporating environmental education in schools can be effective tools towards educating the public on existing and new government policies on plastic pollution, the prevalence of microplastics, and its implications to public health based on existing scientific studies.

RQ3: Can the lessons learnt/experience gained by the Norwegian DRS be adapted and implemented in the Nigerian context?

Norway has consistently improved their plastic bottle return rate over time, with an average return rate of 90% since 2018 with the DRS. This suggests that the management of this scheme as well as the stakeholders involved have passed the learning curve and have gained a high level of competence in handling some of the issues that may disrupt operations, the successful management of running the scheme, and improved results from the scheme.

The study area for this research, when compared to the national Norwegian DRS, can be described to be of a finer scale. Although the scale differs, the researcher believes that the core principles and the operational mechanism of the scheme provide valuable insights applicable to the UNN. The remarkable success attributed to this scheme is a result of key features such as financial incentives for consumers, standardized container designs to facilitate recycling, and a combination of automated and manual collection systems. These elements are not inherently dependent on national-scale implementation and can be adapted to smaller communities.

Furthermore, the UNN is a structured environment with a PBSW manufacturing company within the campus, coordinated access to wholesalers/retailers and the consumers, which makes it suitable for this study. One of the key objectives of this research and choice of study area is to provide empirical data on user behaviour, logistical challenges, and system efficiencies, which are crucial for informing potential national scale-up strategies following the implementation of the DRS framework. Based on the findings of this study, and the lessons learnt from the DRS in Norway, an implementation model for a DRS in the UNN, adapted to suit the current infrastructural and socio-economic situation in Nigeria is presented in Figure 6.

The framework, when implemented, will serve as a ladder to bridge the gap between the current linear pathway to the possibilities of achieving a circular economy of plastic through reuse, recycling, resource recovery, etc. Also, it will serve as a solution to the problem of the indiscriminate disposal of PBSW waste and prevent its leakage into the environment. Circular economy principles promote the concept of waste as a valuable resource; recycling PBSW waste in Nigeria will reduce greenhouse gas emissions associated with the LCA of virgin plastics from cradle to grave, starting with material extraction [57].

LCA is a tool that provides a comprehensive and systematic analysis of the environmental impacts of a product or process from raw feedstock extraction through its end-of life (i.e., cradle-to-grave). Ref. [58] reports that the LCA of PET recycling permits the reduction of up to about 30% global warming potential (GWP, measured as kgCO2 eq) when compared to virgin PET plastics. Potentially, the recycling rates for PBSW can be improved with a reduction in the cost of collection and cleaning which makes up a significant amount of the overall cost of recycling in Nigeria.

RQ4: Can the good practices responsible for the successful implementation and ownership of the Norwegian DRS be modified and applied towards improving current practices of plastic waste management in Nigeria?

The principle of a circular economy emphasizes the importance of changing the perception of used plastics as waste; rather it should be seen as a new resource reusable for the same or other suitable purposes. Implementing an effective strategy for the collection of used plastics is the first step in achieving this circular economy goal. The Norwegian DRS has been very effective in the successful collection of plastic bottle and aluminium cans used in packaging beverages. The consistency observed in the increasing performance of the scheme has made it attractive for adoption in other countries. The findings from this study from both the survey and interview reveal that the following adaptations from the Norwegian DRS can be applied to the Nigerian socio-economic context.

1. Establishment of a value chain for all the stakeholders in the plastic waste management sector in Nigeria, which incorporates recycling companies, the informal sector such as plastic waste pickers, government waste management authorities, the legislative arm of government responsible for law making, etc.

2. When there is a market for those that can recycle, although there is not the sachet water waste in Norway, but it has been discovered from this research and from previous studies as the most prevalent and problematic plastic waste in the country, causing serious environmental issues. The deposit amount for the sachet water and plastic should be significant enough to compel/induce a positive behaviour or attitude towards the return. (In Norway higher deposits are used for smaller 50cl bottles that are perceived to be easily discarded, but because of the high deposit, it induces positive behaviours in consumers to keep them after use to claim back the deposit.

3. Provision of separate bins for the proper disposal of plastic waste will facilitate a sustainable collection system for plastic waste. This will help in the provision of data for plastic waste in Nigeria which is lacking.

4. Manufacturers can collect from their customers using the same vehicle they used in supplying them. The waste management authority ESWAMA can also pick up from manufacturers from recycling plants, or manufacturers can take them to local recycling facilities nearby.

5. Non-cash benefits like receiving some packs of bottled water, and bags of sachet water in exchange for returned bottles or sachets of water may also be some of the options as incentives attached to the DRS in Nigeria.

6. One of the interviewed stakeholders who works in a prominent restaurant that also retails plastic bottle water in the university, mentioned that the restaurant will be willing to be part of the DRS as the money received as incentives by consumers who return their PBSW waste can be used in buying food or snacks by the consumers, explaining that this will also increase sales for the business by encouraging patronage for their restaurant.

Furthermore, there were concerns raised by the two retailers that participated in the interview as regards space management. Based on the economic status of the country, it is likely that the scheme might start out with manual redemption points for returned plastic waste before the technological advancement into using automated vending machines as observed in Norway and other developed countries. Despite the advanced technology operating in Norway, there are still manual redemption points to promote inclusion and cater for those unable to use the vending machines. In the same vein, due to an insufficient waste management infrastructure in Nigeria, it is pertinent to measure the impact and ensure continuous process improvement of the framework using tools like Sustainable Value Stream mapping (SVSM) in tackling and measuring the impact of various identified constraints associated with the scheme for different regions after implementation. SVSM is a growing area of research which builds upon the principles of value stream mapping (VSM), combined with a set of sustainability metrics to visualize and evaluate the environmental impact, and societal well-being. Although, originally used in the manufacturing process, it has been applied in different fields such as production, sustainable supply chain management, and other sectors [59]. It will be beneficial in the monitoring and improvement of the plastic waste management system in developing countries.

Implications and Future Works

The findings from this research will be significant in reducing some of the challenges associated with plastic waste management and plastic pollution in Nigeria and other African countries in the following ways.

1. The results from this research on the current level of awareness of consumers and relevant stakeholders in the plastic waste management sector will provide government and other NGOs interested in creating awareness on plastic pollution with a clear picture of the appropriate content for raising awareness or campaign programmes to educate the public based on their current level of awareness of the impact of plastic pollution on the environment as identified from this study.

2. This study further affirms the proposals from the studies by [39,49,50] on the use of a market-based incentive like the Norwegian DRS to induce pro-environmental behaviours, increase the rate of plastic waste collection, and mitigate the littering of plastic waste.

3. Applying the implementation model developed from this study will help in instituting a plastic waste collection system in Nigeria. This will significantly help to reduce the impact of plastic pollution in Nigeria such as the littering, occurrence of flooding because of blocked drains, the degeneration of road pavements, etc., resulting from the improper disposal of plastic waste.

4. Furthermore, it will help to have a reliable database for plastic waste generation which can be a motivation for investors in the plastic waste recycling industry and help to facilitate the establishment of a value chain or network of organizations in the sustainable supply chain of plastics to achieve a circular economy. Looking towards the future perspectives, the implementation framework can be a starting point for further studies in plastic waste management which can be further extended to other developing African countries.

Importantly, a multi-disciplinary approach which involves top global manufacturers of plastic packaging/products from different sectors, key government parastatals such as the United Nations, and strong collaborative efforts from governments across the globe is crucial for a significant positive change in combatting plastic pollution.

5. Conclusions

The investigation of the awareness of consumers and the relevant stakeholders of the impact of plastic pollution in this study reveals that the current level of awareness of consumers and other stakeholders is still at the level of macroplastic. This is physically observed as plastic litter (68.2%), leading to the blockage of canals (65.0%), an excessive rate of flooding (19.1%) and other related issues; effective channels of creating awareness and educating the public on plastic pollution are social media (48.3%), school education (23.3%), mass media (21.7%), and others (6%). Awareness can be increased through targeted government policies that reward sustainable plastic waste management practices, public awareness campaigns, and the use of social media influencers. Increased awareness of the short-term and long-term consequences of plastic pollution on the environment and public health consequences, can help to induce positive behaviour of responsible disposal and willingness to participate in the DRS by all stakeholders. An implementation framework for sustainable plastic waste collection was developed from the research findings, adapting the Norwegian Deposit Return Scheme (DRS) to suit the current socio-economic context of the population. Additionally, this study affirms that incentives like cash, free packs of water, discounts on food or snacks, etc., can motivate consumers to participate actively in the scheme. The framework designed from this study, when established, can serve as a sustainable plastic waste collection system for PBSW waste in the UNN and can be extended to other regions in Nigeria with further studies.

6. Limitation to This Study

The study area for this research is a university community, which can be assumed to have higher knowledge than the average Nigerian citizen. However, the study involved non-academic staff and other stakeholders in PBSW waste management in the state, representing different categories of citizens in Nigeria. Notably also, previous studies in various universities in Nigeria have also confirmed similar challenges of awareness and inefficient waste collection systems exist in other parts of the country. There is a need for further studies covering other regions of the country, incorporating the peculiarities of each region such as cultural beliefs, literacy, and the existing social structure.