1. Attitudes towards Plastics
Studies on the attitudes towards plastics, including microplastics, have been conducted on different groups of people, particularly students
[1][2] and the public in different countries such as China
[3], Greece
[4] and Indonesia
[5]. The studies are predominantly quantitative surveys
[6][7][8] though other forms of studies in this genre such as qualitative surveys
[9], implicit and explicit attitudes measurement
[10] and evaluation of applications of different polymers aiming to change attitudes
[11] were also conducted.
These studies revealed that the respondents generally have negative attitudes towards different aspects of plastics, namely plastics pollution
[2], impacts of plastics on human health
[3][7], plastic packaging, microplastics and plastic waste
[10], inappropriate disposal of plastic waste
[5] as well as products containing microplastics
[12]. While numerous studies were dedicated to students, due probably to the interest in identifying the current shortcomings and the potential effects of education on their attitudes towards plastic pollution
[1][2][6], there was also increasing attention on farmers’ attitudes towards microplastics as plastic materials such as plastic mulch films and nettings are increasingly used in the agricultural sector
[13][14][15]. A study revealed that most of the participating farmers (88.3%) showed apprehension on the extensive use of plastics for farming, and 67.6% of them associated plastics with negative words such as dirty, waste and eyesore
[13].
The popularization of biobased biodegradable plastics globally as a substitute for conventional plastics has resulted in the increasing entry of these plastics into anaerobic digestion (AD) facilities, which may not be entirely welcome by the stakeholders of such facilities. This was reflected in the negative attitude of the stakeholders participating in a qualitative survey who expressed the difficulty in distinguishing these plastics from other plastic types
[9]. When distinction was made between explicit attitudes characterized by deliberate attitudes a person is conscious of and implicit attitudes that are automatic and shown unconsciously, negativity towards plastic packaging, plastic waste and microplastics was found to differ among German participants
[10]. They showed more negative implicit attitudes towards plastic packaging and plastic waste than microplastics and more negative explicit attitudes towards plastic waste and microplastics than plastic packaging
[10]. The attitudes of the public towards environmental and human health impacts of microplastics were generally negative
[7], but there was greater negativity towards the environmental impacts of microplastics than their human health impacts in terms of risk perception in a German survey
[12].
There was generally a positive attitude towards the control of plastic pollution. Students reported that they were willing to use biodegradable bags for shopping, reject plastic bags while shopping, raise awareness about plastic pollution, fund environmental campaigns and initiate such campaigns, reuse plastic products, and use single-use plastics sparingly
[1][2][6]. Similarly, the public in Shanghai (approx. 68.7%) expressed their willingness to reuse plastic bags, for instance, as garbage bags despite the fact that 75% of them admitted buying plastic bags at relatively high frequency when shopping (a current manifestation of behavior contrasted by a positive attitude towards reusing plastic bags)
[3], whereas those in Greece (>80%) were receptive to the taxing of single-use plastics and the banning of products containing microplastics
[4].
Some attitudinal studies also sought to test out certain established psychological theories such as the Theory of Planned Behavior associating behaviors to the intention of engaging in the behaviors which is in turn determined by attitudes, subjective norms and perceived behavioral control in new settings
[16]. A study among 606 public members in New South Wales Australia found environmental concern to significantly influence attitudes, subjective norms, perceived behavioral control and intentions in pro-environmental plastics consumption while health concern significantly influenced attitudes, subjective norms and intentions
[7]. Knowledge is linked to attitude through the knowledge, attitude, practice (KAP) theory, which promulgates knowledge as a determinant of attitude, and attitude subsequently influences behavioral change
[17]. It is frequently added to the Theory of Planned Behavior as in the study of Borriello et al.
[7]. The study revealed knowledge to positively affect environmental concern, health concern and intention, but it only has a partial positive correlation with attitudes. The study highlighted habits as an important determinant of behaviors. Salazar et al. studied the KAP of fourth grade elementary school children and their parents towards plastics and showed a lack of correlation of knowledge and attitudes of the children to the reuse of lunchbox materials
[8]. Higher knowledge among the children was linked to lower plastics consumption and, surprisingly, a lower willingness in recycling, thus, implicating their preference for reducing over recycling
[8].
2. Implications of the Current Attitudinal Research towards Curbing Plastic Pollution
Association has been drawn between knowledge and attitude through KAP theory, and this is resonated by the studies of Ferdous and Das
[2], Deng et al.
[3], Dowarah et al.
[6], Salazar et al.
[8], Borriello et al.
[7] and King et al.
[13]. These studies generally call for education or better-designed education, publicity and awareness raising to impart the desirable attitudes towards plastics consumption and disposal, thus placing the role on educators, parents or governments. Ferdous and Das asserted that knowledge is important but is insufficient to effectively influence attitude and behavior
[2]. Charitou et al. differentiated experience from non-experiential knowledge and stated that the former is better in shaping pro-environmental attitudes
[4]. It is echoed by Salazar et al. that when certain practices of parents became easily observable by and closely related to their children, there were greater positive influences on the children’s attitudes and practices
[8].
Deng et al. warned of the counteraction of convenience and habits on the positive effects of knowledge of environmental microplastics and their health impacts on the willingness to reduce microplastics
[3]. Habits as a reason behind the incongruence between high negative attitudes and plastics consumption, in addition to low perceived behavioral control, were also highlighted by Menzel et al.
[10]. The perception that reducing plastics consumption is difficult due to the presence of plastics in many items used in daily life probably contributed to the low perceived behavioral control. Borriello et al. incorporated habits into the Theory of Planned Behavior and found habits to significantly determine behaviors, specifically in checking if a product contained microplastics
[7]. The respondents were reported to habitually not checking the microplastics contents, and this brings to attention that breaking habits is crucial since habits are barriers to behavioral changes
[3][7][18]. With fewer barriers and the availability of feasible alternatives, such as substitution or removal of plastics contents in necessary items, behavioral changes are more likely to align with the negative attitudes towards plastics
[3][10]. This was also reflected in the substantial preference of secondary school students in UAE for eco-friendly products and awareness campaigns to reduce plastic pollution
[1]. Government intervention seems important to address the influence of habits, such as through campaigns and certification of microplastics-free products
[3][7].
At the individual level, socioeconomic factors are at play in deciding whether to pay for plastics-free products or clean-up activities. For instance, buying power could affect one’s willingness to pay for plastics-free products
[4] while young, educated and environmentally conscious respondents were more willing to pay for clean-up activities
[5]. However, the influences of socioeconomic factors vary with studies; for instance, willingness to pay to control plastic pollution was affected by buying power which correlated positively with age in one study but was found to be more prevalent among young people in another. Inconsistency in the effect of education level on the attitudes towards plastics was also observed with some studies reporting insignificant effect while others found it significant
[3][5][6]. There was a greater consensus that females are generally more environmentally conscious and more willing to control plastic pollution than males
[3][4][6][8]. Borriello et al. observed a lower intention to purchase microplastics-free products among female respondents and those with lower income, confirming the positive effect of buying power on paying to control plastics pollution but contrasting the higher willingness of females to act
[7]. Targeting socioeconomic factors to positively alter attitudes towards acting against plastic pollution and impart negative attitudes towards plastic pollution is challenging due to inconsistent findings such as those on education level and the complexity of addressing factors such as buying power, which relates to multiple factors at different levels such as economic conditions and policies, minimum wages, cost of living, prices, etc.
[19]. Furthermore, improving education level is not equivalent to imparting awareness and changing attitudes through education because there is a nexus of factors at play in raising education level such as economy, education policies and income
[20]. Social factors, particularly social pressure, might be beneficial in influencing one’s plastics consumption provided that negative attitudes towards plastic pollution have become a norm
[7]. This pressure, together with one’s awareness, cognition and attitudes could be transformed into evaluative reactions such as guilt to promote pro-environmental behaviors
[21].
An important message that emerges from the studies reviewed is that government intervention is necessary because it is too challenging to act at individual level against plastic pollution, particularly when feasible alternatives are not available and multiple barriers are present. While education and social pressure could contribute to desirable attitudes and behaviors, they are somehow linked to government policies. Policymaking and regulations of plastics have been mentioned in multiple studies, particularly the banning of conventional plastics, enforcement of laws to reduce plastics consumption and, hence, pollution, a regulatory approach to switch to biobased biodegradable plastics for food packaging, as well as establishing guidelines for the use and reuse of plastics and standards for packaging materials sent to AD
[1][4][6][9][10][13][21][22]. It has been emphasized that plastics prohibition should come hand-in-hand with enforcement and monitoring without which such prohibition is prone to failure. This was evident in Africa where legislative bans on the use, manufacture and sale of plastic bags yielded low effectiveness due to a lack of enforcement, proper implementation and coordination
[23]. In relation to farming, government policies to monitor and assess the levels of plastics and microplastics in soil as well as those on the economic and practical feasibilities of plastic substitutes comprising biobased, biodegradable and compostable plastics have been proposed to characterize the extents of plastics pollution and ameliorate the pollution
[13]. Sun et al. placed the role to reduce the environmental impacts of plastic substitutes on governments because governments have the power to equip or push for the equipping of existing facilities for treatment of biodegradable plastics
[22]. As for the public in Germany, there was a general willingness to support plastics-regulating policies
[10]. This implies a greater tendency for the public to comply and support law enforcement if they support the regulatory approach.
Studies also highlighted the role of governments in raising awareness and changing attitudes through government and community regulations besides publicity among farmers on proper disposal of plastic mulch films and continual efforts to educate the public on plastic pollution
[12][14]. Studies indicated a shared responsibility of awareness-raising and attitude-changing among educators
[2][8]; the public—for instance via publicly funded mitigation of marine plastic pollution and campaigns
[5][7]; and the media
[6][22]. Another important message is the creation of an ecosystem of plastics consumption and disposal by governments
[1][9][22]. Such an ecosystem has the potential to drive the roll-out and disposal of plastic substitutes, the supply and demand of preferred packaging, the eco-informed selection of polymers used for different applications and recycling or disposal of the polymers, as well as the provision of facilities to treat biobased and biodegradable plastics.
An ecosystem or economy for plastics have been mentioned in a few studies, and governments were deemed to play a crucial role in developing it
[1][22]. In fact, the existing approaches to plastic pollution give a hint of such an ecosystem where a market for plastic substitutes is established through policies, regulation and education to promote their uses and control the consumption of conventional plastics. Furthermore, the ecosystem also includes using and reusing plastics. This subsequently spurs the sectors related to plastic substitutes such as collection, segregation and disposal. Concurrently, the market for recycling of conventional plastics thrives.
3. Probing the Emerging Concept of ‘Plastics Recycling Ecosystem/Economy’
The reason that this concept has received interest is because it aligns with an emerging approach of managing plastic pollution, namely circular economy which integrates the concept of industrial ecology
[24][25]. The theme emerged from a survey among secondary students in the UEA and an analysis of the comments on social media in China on the approaches to manage plastics
[1][22]. To probe the theme of plastics recycling ecosystem and economy further, a search in scholarly databases with a combination of keywords comprising plastics, recycling, ecosystem, economy such as plastic economy, recycling ecosystem and plastics recycling ecosystem was conducted. The articles retrieved were screened with the following criteria to ensure that they align with the concept of plastics recycling ecosystem and economy: (1) The articles must present and explore the overarching concept of economy and ecosystem, not just the recycling of plastics; (2) The articles must be peer-reviewed and published in the past 5 years; (3) The articles must be related to the overarching management of plastics and plastic waste and are not overly focused on or limited to specific technologies such as gasification, pyrolysis, mechanical recycling, etc. (4) The articles must ideally present the different facets of the overarching plastics ecosystem/economy.
The literature search and screening yielded articles bearing the phrase ‘circular economy’. Circular economy seems to be the buzzword used in many experimental studies and reviews related to the treatment and recycling of plastics
[26][27], and few actually focus on exploring the framework, concept and implementation of circular economy as a whole. Circular economy has become a trend, and the most popular definition is probably that of Ellen MacArthur Foundation which calls circular economy a substitute of the ‘end-of-life’ concept characterized by innovative design, production and business models to incorporate renewable energy, reuse and eliminate waste
[28].
Multiple studies have pointed to the shift of plastic economy from a linear to a circular one as an important solution to plastic pollution. Subsequent to literature screening, a summary of eight different study types related to circular economy shows that all these studies base their definition of circular economy on that of promoting the reduction, reuse, recycling and recovery of plastic waste through a lifecycle approach from the design to the disposal of plastic items
[26][29][30][31]. There was a significantly greater interest in the management of plastic waste, particularly its reuse, treatment and recycling
[26][30][32], in comparison to the design and production of plastics for circularity
[31]. Other than those on technical advances of plastic waste treatment, recycling and valorization
[33], the studies on circular plastic economy are also extended to identifying the barriers to specific aspects of the economy such as digital innovation
[29] and challenges of the circular economy as a whole
[31], examining the relevant policies and policy instruments
[30][34], as well as developing frameworks and models for its implementation
[32][35].
These studies highlight the importance of policies, mechanisms and regulations to hold plastic producers responsible for plastic waste reduction and treatment, of addressing the entire plastics value chain rather than banning single-use plastics, as well as incorporating industrial symbiosis and cradle-to-cradle approach to realize circular plastic economy
[30][34][35]. Currently, some countries have passed and enforced bans on single-use plastics, such as the Single-use and Other Plastic Products (Waste Avoidance) Act 2020 of Australia, EU’s Directive on single-use plastics, as well as Plastic and Related Products Regulations 2022 of New Zealand. Attempts to shift to and promote circular economy have also been made, for instance, through the EU’s new circular economy action plan adopted in March 2020
[34][36]. Infrastructural and technological development to more efficiently segregate waste, recycle and valorize plastics was also emphasized
[26][31][32][37]. The role of governments in these endeavors towards circular plastic economy has been reiterated
[26][29][30][37]. Digital innovation and data analytics have been brought into the context to spur the circular plastic economy
[29][32]. The acceptance of digital innovation for circular plastic economy among the public, however, could be challenging, if they still struggle to grasp the concept of circular economy. While governments are perceived to have an extensive role in circular plastic economy, it has been underscored that collaboration between governments and industrial players is crucial to garner commitment, propel technological innovation and ensure its success
[30][37].
4. Merging Circular Economy with the Approaches to Control Plastic Pollution from Attitudinal Research
The concept of circular economy generally fits into the idea of recycling ecosystem/economy mentioned in the attitudinal studies
[1][22]. It was mentioned that recycling of plastics could be enhanced by improving cognition whereas the effective execution of circular economy by incorporating government and community regulations could improve cognition
[14]. A study among elementary school children revealed that knowledgeable children preferred reduction over recycling, and a reason given was that they might perceive recycling as less impactful to control marine plastic solution than reducing plastic use altogether because plastics are still generated and could eventually enter the environment
[8]. In fact, the low global plastics recycling rate (9% as of 2019) and the increasing number of mismanaged plastics entering the environment (22% as of 2019) indicate that the circular plastic economy is still at its infancy
[38]. The need of a multi-pronged approach to combat plastic pollution is necessary, and this is captured in the study of Karayilan et al.—that embedding the use of bio-based biodegradation plastics and industrial symbiosis into circular economy is desirable
[35]. The idea of industrial symbiosis is in line with the positive attitude among AD plant stakeholders on the prospect of increasing methane yield from biobased biodegradable plastics if the problems of segregating them from other plastics can be solved
[9].
Tapping into the willing attitude of the public to support policies and laws related to controlling plastic pollution
[4][10] and their positive attitude towards contributing to reduce plastic pollution
[5][6][22], it is crucial to reduce the barriers they encounter currently in acting against plastic pollution. This involves providing and popularizing alternatives for conventional plastics such as biobased biodegradable plastics and stepping up circular economy by designing plastic items that facilitate reuse and recycling. This permits circular plastic economy to be executed on the proportion of conventional plastics and a simultaneous shift to the economy or circular economy of biobased biodegradable plastics. Governments play a pivotal role in such efforts by providing the policies, regulations, enforcement, guidelines and awareness. The awareness could be subsequently enhanced through public efforts. It is clear that a lack of options and habits overpower negative attitudes towards plastic pollution and, hence, behavioral change. It is unlikely that there will be significant reduction in plastic waste generation and plastic pollution without government intervention and a paradigm shift in the plastic economy.