5. Elements to guide policy action

Microplastics are pervasive in the environment. As our human population and dependence on plastics continue to grow at current rates, it is expected that microplastics concentrations in aquatic environments and the associated risks will steadily increase. According to the precautionary principle, precautionary measures should be considered when the environmental and human health risks are uncertain and the potential consequences of inaction are high. In the case of microplastics, effective preventive action is recommended in order to halt the accumulation of microplastics in the environment and prevent widespread health risks to ecosystems and human health.

The generation of microplastics from textile products and vehicle tyres is a complex phenomenon, for which no single effective technological or policy fix exists. Microplastics emitted at different points of the lifecycle of products differ in their characteristics, entry pathways into the environment and inherent potential to cause harm. This underlines the complexity of designing policy solutions to comprehensively target textile- and tyre- based microplastics in marine and freshwaters.

Key elements to take into consideration when evaluating different mitigation entry points are outlined in Table 5.1. Measures aimed at preventing the emission of microplastics at source are likely to have the largest mitigation potential. Especially for diffuse sources of pollution (i.e. Tyre and Road Wear Particles, microfibres emitted into air during wearing and drying), the Principle of Pollution Prevention reflects that pollution prevention is often more cost effective than treatment/restoration options downstream (OECD, 2017[1]). Yet, given the diffuse nature of emissions and the variety of entry pathways, measures upstream cannot entirely alleviate the risk of microplastics pollution for the water cycle. Measures upstream will need to be complemented by effective end-of-pipe capture solutions to impose, incentivise, or encourage improved end-of-pipe capture.

The most cost-effective way of tackling the issue is likely to consist in the implementation of a mix of policy tools targeting different mitigation entry points along the lifecycle of products. Lifecycle approaches are also likely to benefit from higher levels of stakeholder acceptance and easier implementation overall, as they aim to target several relevant actors and share responsibility for pollution prevention and management.

At the same time, current scientific evidence on the hazards associated with textile microfibres and TRWP may not yet be sufficient to justify resource-intensive policy efforts. Researchers and industry have identified several mitigation best practices and technologies that can be implemented during the lifecycle of textiles and tyres to prevent or reduce emissions. Yet, often further research is required to evaluate their relative cost-effectiveness, implementation feasibility and the potential trade-offs with other relevant environmental benefits. Certain end-of-pipe mitigation options, such as advanced wastewater treatment or nature-based solutions, primary designed to mitigate other pollutants, can generate significant co-benefits for microplastic mitigation, although microplastics pollution alone is unlikely to justify the additional capital and operation & maintenance costs.

In general, current scientific evidence alone may not be sufficient to drive costly investment decisions or to justify trade-offs with other relevant environmental consequences. Furthermore, further knowledge and data is still required in several areas (e.g. mitigation effectiveness, including the need for standardised test methods to measure it, the magnitude of current emissions, information about the full life-cycle impacts of interventions), in order to evaluate the cost-effectiveness of different mitigation measures. Based on these considerations, the next sections present key recommendations to guide governments and other stakeholders towards improved control of microfibre and TRWP mitigation. These are organised around two priorities:

  • Advancing knowledge to strengthen the evidence base and inform policymaking via the fostering of research, the promotion of international and cross industry collaboration, the development of harmonised test methods; and

  • Seeking out and valuing co-benefits with other environmental policy areas (e.g. circular practices in the textile and apparel sector, sustainable transport policy, water quality policies, guidelines and strategies for plastics) and exploiting low-cost “no regret” mitigation measures.

Additionally, when information on the effectiveness of mitigation measures has improved, additional and more specific policy measures will be needed to mandate, incentivise or encourage the uptake of mitigation technologies and best practices. As outlined in Chapter 4, some of these policy measures, such as requirements to add microfibre filters to washing machines and consumer-awareness initiatives, are already being explored by governments.

Preventive mitigation action should be in line with wider objectives of environmental and health protection. Measures taken should be proportional, consistent with existing policy frameworks, based on adequate cost-benefit analysis considerations and sufficiently flexible to encourage scientific research and allow for innovation in mitigation solutions. In particular, it will be crucial to consider holistic system-wide impacts of proposed measures, to ensure that these do not cause unintended adverse consequences, such as burden-shifting towards other environmental policy areas. This could be the case for instance of higher resource use associated with the use of alternative materials during product manufacturing, or increased terrestrial microplastics pollution as a consequence of sludge application and improved wastewater treatment technologies. Evidence-based impact assessments of proposed measures will need to be carried out in order to ensure that policy measures are cost-effective and ensure net environmental benefits.

There may be a case for prioritising the implementation of mitigation technologies at pollution hotspots, to achieve a higher cost-effectiveness of the mitigation measures. For instance, prioritising the implementation of microfibre filters at commercial (e.g. restaurants, hospitals, etc.) and industrial laundering facilities could potentially enable the capture of microfibres from highly polluted wastewaters as close to the source of emission as possible and before these diluted into sewage. Similarly, the allocation of improved wastewater and stormwater technologies can be optimised to prioritise the treatment of highly polluted wastewaters or road runoff. On-site treatment generally tends to be less cost-effective than upgrading centralised WWT technologies, however this may not be the case for low-cost improvements in stormwater management and treatment. As outlined in Chapter 3, there may be large pollution prevention gains to be made by directing the implementation of low-cost stormwater treatment technologies at TRWP pollution hotspots, i.e. locations with high potential for the generation of TRWP and/or direct transportation into the environment. Country-specific hotspot analyses will be required in order to identify potential pollution hotspots for microfibres and TRWP and assess whether the implementation of ad-hoc treatment and filtering technologies is more cost-effective compared to large-scale installations.

Sound scientific evidence will need to play a key role in the determination and implementation of policy measures. Opportunities to extend and deepen the evidence base for intervention include:

  • Better data quality and gathering on the quantities and concentrations of microplastics in the environment, including broadening the scope to all relevant loci of concern (e.g. marine and freshwaters, air, soil, sediments, aquatic and marine species and the human body);

  • Improved understanding of the concentration levels at which adverse health effects occur;

  • Development of risk assessments and forecasting on the hazards posed to humans and ecosystems. Further research is particularly required to assess risks in realistic environmental concentrations, as well as to close existing knowledge gaps with regards to the fragmentation of plastics and the hazards posed by smaller microplastics and nanoplastics;

  • Improved understanding of the quantities and release mechanisms for textile- and tyre-based microplastics release, also including industrial emissions, end-of-life leakage and other relevant stages of the use phase (e.g. wearing and drying of garments)

  • Research and development of mitigation technologies and best practices implementable at different stages of the product lifecycle, from manufacturing to end-of-pipe measures for stormwater and wastewater; and

  • Improved evaluation of the relative cost-effectiveness of the mitigation measures available along the lifecycle of products.

There is also a need to support to the identification, development and assessment of mitigation technologies and best practices along the lifecycle of products. At the manufacturing stage, further efforts are required to develop innovative textiles and vehicle tyres that undergo lower abrasion, without compromising on other relevant characteristics. Further research is also required to develop best practices and technologies for the design and manufacturing of complementary products (e.g. washing machines and laundry detergents) and infrastructure (e.g. roads and roads) which cause lower product abrasion and mitigate MP generation. At the use stage, further research is required to assess the mitigation potential best practices and technological solutions that have been identified as well as of the possible entry points for their implementation (e.g. household vs commercial or industrial washing machines). At the end-of-pipe stage, further research is required to assess the effectiveness of available options to reduce microplastics in stormwater and wastewaters. Overall, there is a need to perform evaluations of the relative cost-effectiveness of mitigation measures available to inform intervention action.

In order to accelerate research and perform robust risk assessments, it will be crucial to agree on common definitions, standardise and harmonise data types and share existing information. Currently, the use of different methodologies and definitions makes it difficult to compare and aggregate findings and constitutes a vast bottleneck in several fields of action. International and interdisciplinary cooperation and information sharing will be key enablers the advancement of research and to the standardisation and harmonisation of test methods. Further, the development of common databases to establish cross-border access to harmonised data can reduce time and costs associated with documenting robust policy decisions at national and international levels.

In particular, the following list of recommendations can facilitate methods harmonisation and international collaboration:

  • Agreeing on common definitions and methods to sample and analyse microplastics in the environment and to report results on adverse health effects on ecosystem and human health.

  • Defining common and harmonised standards for microfibre shedding and tyre tread abrasion. Currently, the lack of standardised test methods to measure microplastics shedding poses a key barrier to research and mitigation. As outlined in Chapter 4, ongoing efforts and stakeholder collaboration to establish standardised and harmonised test methods for microfibre shedding and tyre tread abrasion will be crucial to accelerate research and enable the implementation of mitigation measures such as minimum standards and labelling and information schemes.

  • Defining uniform protocols to measure and evaluate the effectiveness of mitigation technologies, including standardised criteria to assess the effectiveness of different stormwater treatment infrastructure to retain TRWP.

  • Developing standardised measurement procedures for the sampling and analysis of microplastics in different environmental media (e.g. TRWP, MP in wastewaters and stormwater)

  • Establishing international databases and information exchange platforms to improve accessibility to available knowledge, exploit synergies across different projects and accelerate research.

  • Improving accessibility on best manufacturing practices and technologies to prevent information asymmetries and enable industry to develop and implement mitigation measures

  • Promoting international and interdisciplinary collaboration. The promotion of international and interdisciplinary collaboration will be a key enabler for the objectives outlined above, in particular to accelerate research, establish cross-border access to standardised data and inform policy responses. Existing voluntary initiatives to establish stakeholder platforms should be sustained to facilitate the dissemination of knowledge in the long-term.

Given the significant trade-offs and often high costs involved, it is unlikely that microplastics pollution alone will drive policy decisions. As outlined in earlier parts of the report, a strategic way of addressing the issue of microfibres and tyre-based microplastics could consist of seeking out and valuing co-benefits with other environmental, climate, human health, or safety policy areas while not compromising progress on microplastics mitigation. Where other policy objectives drive investment and policy decisions, there may be scope for integrating microplastics into existing frameworks to achieve pollution reduction at a low-cost. There are also several cases of “no-regret” policy opportunities, where mitigation action for microplastics pollution either comes as a co-benefit of measures in other policy areas, such as in the case of the reduction of total transport volumes, or bears low costs and low risk for unintended consequences, which could be the case of new technological innovations in the production of textiles, tyres and complementary products. Drawing from the analysis of Chapters 2-4, the following paragraphs outline key opportunities to prioritise synergistic and/or low-cost microplastics mitigation interventions along the lifecycle of textiles (Section 5.3.1) and tyres (Section 5.3.2) and at the end-of-pipe stage (Section 5.3.3).

Several potential synergies exist between actions to mitigate microplastics pollution from textiles and actions aimed at prompting a transition towards a more circular textile sector. Crucially, fibre shedding reduces the serviceability of garments, so practices aimed at reducing fibre release generally also contribute to enhancing the durability of textile products. Given the high environmental impacts associated with the lifecycle of garments and the current linear nature of textile value chains, there is a strong case for embedding microfibre mitigation measures into sector-specific policymaking for the textile and apparel sector.

In general, a holistic approach to the mitigation of textile microfibres is required in order to also take into consideration potential trade-offs with other environmental impacts (e.g. climate impacts, land use, chemicals use and water pollution, resource use) and risks for potential burden-shifting. Notably, as discussed in Chapter 2, there is a strong case for focusing interventions which reduce shedding rather than substituting away from synthetic fibres in textile and apparel manufacturing, given that the production of cellulose-based fibres can bear significant environmental and climate impacts and that cellulose-based microfibres are abundantly present in the environment.

In particular, the following strategic measures are proposed and detailed in Table 5.2:

  • Promoting cross-industry collaboration and dialogue between the textile sector and other stakeholders, in particular to gain a clear understanding of where and how releases occur and share best practices for microfibre mitigation to inform intervention.

  • Curbing fast fashion trends, in particular promoting higher quality and longer lasting textiles/clothing and the higher uptake of circular business models, via consumer education, awareness-raising initiatives, incentives for eco-design and voluntary action.

  • Mandating minimum eco-design standard requirements in line with the sustainable production and consumption of textiles. Further regulation targeting the microfibre shedding tendency of products can be considered once measurement standards are agreed upon.

  • Requiring or encouraging greater transparency from brands over the products they manufacture or sell, for instance via mandatory or voluntary standardised eco-labelling schemes including the microfibre shedding rate along with a number of relevant environmental and climate parameters.

  • Sharing responsibility for microfibre mitigation across all relevant stakeholders and mitigation entry points, for instance by including parameters relevant for microfibre pollution into minimum performance standards for household, commercial, or industrial washing machines.

  • Promoting international-level voluntary initiatives and targets along the textile and apparel supply chain to promote sustainable production and consumption practices in the sector. Although microfibre mitigation options are not yet envisioned in existing best practices and guidelines for industry action, Responsible Business Conduct and Due Diligence initiatives (see Section 4.3.1) can also contribute to improving sustainability during production, preventing industrial emissions and fostering stakeholder dialogue and engagement.

  • Promoting research and innovation to develop fibres and fabrics with a lower tendency to shed microfibres and a lower environmental impact overall. Once standardised measurement standards are available, it is recommended to incorporate the issue of microfibre shedding into life-cycle assessments for textiles (Sandin, Roos and Johansson, 2019[2]).

Mitigation of microplastics generated during road transport activity offers several key interlinkages and synergies with climate, transport and air pollution policies. As outlined in Chapter 3, TRWP emissions may be reduced via ongoing efforts to reduce overall transport volumes and shift towards sustainable modes of passenger and goods transport. Policies supporting the wider uptake of eco-driving practices, generally aimed at improving safety, reducing GHG emissions and mitigating the impact of road transport on air quality, may also contribute to reducing the emission of TRWP into surface waters. Similarly, policies aimed at reversing trends towards heavier vehicles can reduce fuel consumption, mitigate the impact of road traffic on air quality, while contributing to TRWP mitigation. Despite the numerous co-benefits, as the example of the electrification of the vehicle fleet shows, climate and transport policies will not automatically translate into reductions in tyre wear, which suggests that specific policy action is required in order to adapt existing measures to ensure that these also address microplastics pollution.

In particular, the following strategic measures are proposed and detailed in Table 5.3:

  • Promoting cross-industry collaboration and dialogue between the tyre manufacturing sector and other relevant stakeholders (e.g. road infrastructure developers, vehicle producers, water sector);

  • Introducing mandatory labelling schemes for tyre tread abrasion, along with a number of other relevant environmental and safety parameters;

  • Mandating minimum performance standards for tyre tread abrasion and road surfaces;

  • Promoting reductions in passenger vehicle use and shifts towards more sustainable transport modes by guiding policy and infrastructure investment with a focus on accessibility, to reduce fuel consumption, mitigate the impact of road traffic on air quality and contribute to TRWP mitigation, in addition to other well-being goals;

  • Seeking out and valuing co-benefits with policy measures aimed at reducing exhaust and non-exhaust emissions and their toxicity, for instance via vehicle light-weighting, regulations on tyre composition, measures aimed at managing traffic flows (e.g. speed limits) and the uptake of available mitigation technologies (e.g. advanced driver-assistance systems) (OECD, 2020[3]); and

  • Sharing responsibility for TRWP mitigation across all relevant stakeholders and mitigation entry points, while prioritising intervention as close to the source as possible. Possible interventions include mandating the improved design and maintenance of road pavements, incentivising the production of lighter vehicles, or fostering research on the impact of road markings.

At the end-of-pipe stage, two main sets of mitigation measures exist: improvements in wastewater treatment to retain microfibres present in sewage and improvements in the management of stormwater runoff and road dust to treat diffuse microplastics. In both cases, identifying and valuing co-benefits with other pollutants will be key to improving the end-of-pipe capture of microplastics.

At the level of wastewater treatment, policy options may be limited as costly decisions on the design and operation of WWTPs will not be driven by microplastics pollution alone and sludge management remains an issue. Several policy options exist to finance WWTP upgrades and these are being considered notably to address pollutants of emerging concern (OECD, 2019[4]). Similarly, implementing measures to reduce diffuse water pollution, improving the management of road runoff and preventing the discharge of untreated stormwater into water streams may contribute to reducing the impact of several pollutants on freshwater quality, in addition to also preventing the direct discharge of microplastics (and larger plastic items) into water bodies.

Some key priorities for action are to:

  • Further assess the microplastics mitigation effectiveness of available end-of-pipe technologies, differentiating by MP type and shape and including TRWP and smaller microplastics;

  • Standardise and harmonise analytical techniques for microplastics in wastewater and stormwater;

  • Identify hotspots for stormwater and road runoff (e.g. trafficked roads) and for sewage influents;

  • Further evaluate the microplastics mitigation effectiveness of options to develop and/or improve existing stormwater infrastructure to address a range of diffuse water pollutants;

  • Consider the implementation of measures targeting road dust, such as effective street sweeping and street washing, especially by prioritising hotspot areas; and

  • Consider the implementation of road-side capturing technologies for TRWP (e.g. gully pots), green infrastructure and nature-based solutions (e.g. wetlands) which can also be effective at removing other diffuse pollutants (e.g. nutrients) and adequately maintain existing infrastructure.


[3] OECD (2020), Non-exhaust Particulate Emissions from Road Transport: An Ignored Environmental Policy Challenge, OECD Publishing, Paris, https://dx.doi.org/10.1787/4a4dc6ca-en.

[4] OECD (2019), Pharmaceutical Residues in Freshwater: Hazards and Policy Responses, OECD Studies on Water, OECD Publishing, Paris, https://dx.doi.org/10.1787/c936f42d-en.

[1] OECD (2017), Diffuse Pollution, Degraded Waters: Emerging Policy Solutions, OECD Studies on Water, OECD Pubilishing, Paris, https://doi.org/10.1787/9789264269064-en.

[2] Sandin, G., S. Roos and M. Johansson (2019), Environmental impact of textile fibers - what we know and what we don’t know: Fiber Bible part 2, Mistra Future Foundation, http://urn.kb.se/resolve?urn=urn:nbn:se:ri:diva-38198.

[5] UNEP (2019), Addressing marine plastics: a systemic approach, United Nations Environment Programme. Nairobi, Kenya, https://wedocs.unep.org/20.500.11822/31642.

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