It is impossible to imagine today’s world without plastic. Due to its versatility, affordability and durability, plastic is found in an almost infinite number of applications including clothing, machinery, construction, electronics, transportation, agriculture and packaging, with the last contributing the most to the demand for plastic [1
]. Globally, over 300 million tonnes of plastic are produced each year and the trend is increasing [1
]. Approximately 275 million tonnes of global plastic waste were generated in 2010 [2
], and this figure has increased since then [3
]. While being a positive characteristic during use, the longevity of plastic causes problems at the waste disposal stage: in 2015, the amount of plastic which had accumulated in landfills or the natural environment was estimated to be approximately 5000 million tonnes and it is predicted to increase to 12,000 million tonnes by mid-century [3
The accumulation of plastic in the natural environment also occurs in the oceans. It is estimated that 4.8 to 12.7 million tonnes of plastic entered the oceans in 2010 alone [2
]. Plastic fragments can be found in marine environments worldwide [4
]. Plastic in the oceans does not only cause concerns for the environment and human health [5
], but can also have negative impacts on local economies [6
]. These concerns are shared among supranational organisations, including the UN and the EU, national governments, non-governmental organisations, scientists, and members of the public [7
], who all identify marine plastic as a global problem.
Policy is a lever to address the problem of plastic marine pollution. Many policies have been enacted worldwide aiming to prevent the discharge of plastic into the oceans [6
]. However, in the past, many regulations have been shown to be ineffective at preventing the discharge of plastic into the oceans [7
]. Furthermore, legislation influencing the consumption of plastic products can lead to unintended consequences such as a shift in consumption from plastic to another material [11
]. Therefore, finding effective solutions requires a holistic life cycle approach [7
In 2021, the EU will introduce a market restriction on several single-use plastic items, such as cotton bud sticks, cutlery, plates, straws, drink stirrers and sticks for balloons [13
]. The market restriction is part of the single-use plastics directive which focuses on the 27,000 tonnes of plastic from fishing gear and single-use plastics which enter the marine environment every year in the EU [14
]. Apart from the market restriction, the directive foresees new product design requirements, extended producer responsibility and awareness raising measures [13
]. The estimated reduction in greenhouse gas (GHG) emissions associated with the introduction of the directive is 2.63 million tonnes per year [14
]. The directive states that its “main objective […] is to prevent and to reduce the impact of certain plastic products on the environment, in particular the aquatic environment” [13
The evidence base used for the market restriction is flawed in four ways. First, the life cycle assessment (LCA) does not show ISO conformity [15
]. Second, it does not include the End-of-Life (EoL) stage [15
], which gives an advantage to biodegradable products in the assessment. Specifically, it ignores the methane emissions of biodegradable products when landfilled which is where a third of EU waste ends up [16
]. Third, the LCA performed by the European Commission (EC) only considers air pollutants [15
]. Again, this favours products which are based on agricultural and forestry produce and disregards that these often lead to significant effluents to water bodies. Fourth, the results of the environmental assessment are not communicated transparently. For example, it is stated that “there might be a minor increase in land use due to a switch to paper and wood” [14
]. However, this increase in land use is not further discussed nor quantified.
Not only is the environmental assessment flawed but also the impact assessment makes unsupported assumptions. The EC [17
] assumes that the directive will cause a switch in consumption from single-use items to multiple-use items of 10% to 90% depending on the product. It is furthermore assumed that overall demand will decrease by 50% for some single-use items due to the directive [17
]. However, these assumptions are not justified with evidence. It seems more likely that almost the same number of single-use items will be consumed which would then be made from different materials such as paper and wood [11
There is a lack of studies which assess how plastic compares to other materials available for single-use items. Wood has been the subject of comparative LCAs but only in the construction sector [18
]. LCAs which compare paper products with polymer products only exist for carrier bags. Lewis et al. [21
] reviewed a number of comparative LCA studies and found that “paper has the highest environmental impact in most categories”. In contrast, Mattila et al. [22
] state in their LCA study which took different EoL scenarios into account that they “could not discern plastic, paper, and cotton bags without limiting the analysis to some subset of situations”. A UK Environment Agency study points to the importance of reusing carrier bags and finds that paper bags need to be reused three times to reduce the global warming potential below that of single-use, high-density polyethylene carrier bags [23
LCA has been criticised for not considering mismanaged waste and therefore not taking impacts from plastic marine pollution into account. Boucher and Billard [24
] argue that current LCAs neglect plastic pollution. Schweitzer et al. [25
] as well as Lewis et al. [21
] are critical of the fact that LCAs do not consider environmental leakage in their waste management scenarios. In 2016, a review of quantitative approaches for cause–effect assessments included marine plastic debris but stated that, at the time, there were no effect factors which quantify the effect of marine plastic on biodiversity [26
]. Only recent research has started developing an effect factor approach for entanglement with marine plastic [27
] and assessed the risk of marine littering of plastic bags [28
]. In the present research, we want to build on this research and explicitly include plastic marine pollution in the life cycle impact assessment.
The objective of this study is to assess the effect on the environment of a single-use plastic market restriction on certain consumer items which was proposed in 2018 by the EC [13
]. To achieve this objective, product LCA was conducted for single-use plastic items and single-use non-plastic alternatives. The life cycle impacts of the two product types were compared and scaled according to EU consumption. LCA was identified as the appropriate method for this research as it allows the quantification of environmental impacts of different product systems with the same function. The main research question to be answered is whether the EU single-use plastics ban is appropriate to improve the quality of the marine environment and whether other solutions to the problem of plastic marine pollution exist.
While this paper offers novel insights, it also has limitations. The novelties of this study concern not only the methodology but also the case study outcome. From a methodological point of view, the novelty of this study is the assessment of plastic marine pollution as an impact category. The chosen probabilistic approach is straight forward and therefore easy to replicate by other researchers. The case study deals with the policy assessment of a single-use plastics ban. While comparative LCAs exist for individual product comparisons, there is no literature-based evidence of an environmental policy assessment of a plastics ban which causes a large-scale shift from one product to another. One limitation of this study is that it takes a static approach to consumption and emission levels and considers only one year as a reference period. Another limitation is that the study does not perform an endpoint damage analysis and therefore does not come to a clear conclusion.
This study investigated whether banning plastic items is an appropriate strategy to protect the environment. Product LCAs were conducted for single-use plastic items and single-use non-plastic alternatives. The life cycle impacts of the two product categories were compared and scaled according to EU consumption. This study finds that single-use items cause emissions which are harmful to the environment regardless of their material composition. The common perception that products made from renewable resources are good for the environment is a partial truth and requires further qualification.
According to this analysis, it is unclear whether the plastics ban is beneficial to the environment since positive but also negative impacts on the environment are expected. The single-use plastics ban will decrease the EU’s contribution to plastic marine pollution by 5.5% which equates to a 0.06% decrease globally [2
]. It is concluded that the plastics ban will lead to only a small reduction of global plastic marine pollution and, thus, provides only a partial solution to the problem it intends to solve.
Alternatives to a single-use plastics ban exist, such as banning or imposing a premium price on single-use items regardless of their material composition, to reduce consumption and thereby pollution. Another promising strategy to reduce plastic marine pollution is to refrain from plastic waste exports into countries with high rates of mismanaged waste. An improvement of the single-use plastics ban would be a stronger emphasis on awareness raising to avoid inappropriate disposal in the EU and a requirement for paper and wood products to be certified to come from sustainable forestry sources.
The findings of this study have implications for policy and industry. As mentioned in the introduction, there is a current global trend towards single-use plastic policies. This study might contribute to the evidence base for future single-use plastic policies and support the improvement of already-existing policies. Furthermore, the findings stress that more effort is needed from policy makers to reduce the negative impacts of single-use items and to solve the problem of plastic marine pollution. Moreover, the single-use items industry might be interested in the findings. This study points to advantages and disadvantages in the life cycle of single-use plastic and single-use non-plastic products. The insights provided here could help the respective industries to mitigate existing problems and improve their environmental performance.
Recommendations to policy makers:
The EU should stop exporting plastic waste (short-term).
The EC should follow international standards such as ISO when performing assessments such as LCA (short-term).
The EU should respect the waste hierarchy and increase its efforts to prevent waste. For that purpose, the EU should encourage its citizens to use fewer single-use items (e.g., by imposing a premium price on all single-use items) (long-term).
The EU should focus on the mismanagement of waste and littering instead of banning certain plastic products. Banning is not promising as it would be difficult to ban all plastics (long-term).
The EU should only import certified paper and wood products if it intends to rely more strongly on the so-called bioeconomy (long-term).
Recommendations to industry:
5.3. Limitations and Areas of Future Research
This study could be followed up by a more extensive data collection. To refine the representativeness of the single-use items analysed in this study, a wider market study could be performed in order to reveal the share of products which exist on the market. The assumption that most single-use items are either incinerated or landfilled could be confirmed by a study which assesses the actual recycling and composting rates of single-use items made from different materials. The second assumption which requires confirmation is that the environmental impact of single-use paper products is equivalent to the environmental impact of paper more generally. A specific LCI study could be performed for small single-use paper products. Finally, actual market data on the consumption of single-use plates would have improved the reliability of this study.
Methodologically, a dynamic analysis and a location-specific analysis would improve this study. It would be worthwhile to perform a dynamic analysis of consumption patterns and changes in the background system (i.e., electricity supply) to give a more accurate outlook into the future. Such an outlook could also take into account the potential rise of biopolymers in the near future. Further research could investigate the actual location of emissions, considering the routes taken by single-use items in the global supply and waste chain. This would also help to refine the transportation distances assumed in this study.
This investigation suggests the use of other solutions to the problem of plastic marine pollution. Future research should explore whether the observed reduction in consumption of e.g., plastic bags after the introduction of a levy has led to a reduction of environmental impacts. Furthermore, research should reveal the environmental impacts of waste exports, particularly plastic waste exports. The effects of a plastic export ban in the EU should be investigated including an assessment of the environmental benefits and the feasibility of such an approach.
LCA combined with consumption data seems to be useful in the policy assessment context. It is worth investigating whether a similar approach could be applied to assess the environmental impacts of other industrial policies (i.e., in the transport sector). This could help to ensure that industrial policies are effective as well as beneficial to the environment.