Microplastic

Last reviewed: 7 September 2026

Microplastics is a collective term for small plastic fragments measuring up to five millimeters. They may be manufactured as microplastics or formed through the wear, fragmentation, or degradation of larger plastic materials.

There is currently no universally established definition of microplastics. Microplastics are generally understood to be solid particles of plastic or rubber, regardless of shape (for example, granules, flakes, or fibres), that range in size from 1 nm to 5 mm in their largest dimension and are insoluble in water. Synthetic fibres with a length between 3 nm and 15 mm and a length-to-diameter ratio greater than 3 are also included within this definition. The Swedish Environmental Protection Agency generally follows the European Chemicals Agency’s (ECHA) definition of microplastics but also include biodegradable plastics within this concept.

Microplastics are often divided into two categories: primary and secondary microplastics. Primary microplastics are intentionally manufactured, for example as raw materials in the plastics industry, as exfoliating agents in various products, or as additives in cosmetics. Artificial grassfields can also be a source of primary microplastic emissions, as the rubber granules sometimes used as infill material often consist of newly manufactured granules.

Secondary microplastics originate from larger plastic- and rubber items that have broken down into smaller particles often unintentionally. For example, plastic litter degrades into microplastics in the environment when exposed to sunlight. Secondary microplastics are also generated through the wear and tear of roads and vehicle tyres, as well as from the abrasion of synthetic textiles.

Microplastics in the oceans

More than 150 million tonnes of plastic are estimated to be floating in the world's oceans. Each year, an additional 5 to 13 million tonnes of plastic enter the marine environment. Plastic waste, including discarded plastic products and fishing gear, gradually breaks down into microplastics. Depending on the type of plastic, temperature, and exposure to sunlight, this degradation process can take several hundred years.

Because plastic degrades so slowly, the amount of microplastics in the oceans will continue to increase for a long time, even if the input of new plastic were to stop today. Currently, there are no effective methods for removing the smallest plastic particles from the oceans. The solution is therefore to prevent, or where prevention is not possible, significantly reduce the release of plastics into the environment.

There are still significant knowledge gaps regarding the impacts of microplastics on human health and the environment. Further research is therefore needed to determine their long-term effects.

Are microplastics dangerous?

In 2019, the Swedish Environmental Protection Agency (Naturvårdsverket) reported on a government assignment concerning microplastics. The report concluded that microplastics are unlikely to pose a significant risk to the environment or human health at current concentrations, although there may be specific locations where adverse effects could occur.

However, substantial knowledge gaps remain regarding the extent to which microplastics affect human health and the natural environment, as well as how these effects may vary among different types and sizes of microplastics. There are also significant uncertainties about the degree to which different organisms are exposed to microplastics. As a result, it is currently not possible to draw definitive conclusions about the risks associated with microplastics. There are indications that larger particles may be relatively harmless, while smaller particles may have negative effects. This is particularly true for nanoplastics. Larger particles may also break down over time into smaller particles. Measures to address microplastic pollution are therefore justified based on the precautionary principle and the general rules of consideration in the Swedish Environmental Code.

The Swedish Environmental Protection Agency actively promotes increased knowledge and dialogue on issues related to microplastics. Effective prevention of the generation and spread of microplastics at their source requires cooperation among many different stakeholders.

Sources and emission pathways

In 2017, the Swedish Environmental Protection Agency reported to the Swedish Government on the sources responsible for the largest emissions of microplastics in Sweden.

The investigation identified the following as major sources of microplastic emissions in Sweden:

  • Industrial production and handling of primary plastic 
  • Tyre wear from roads 
  • Artificial grassfields 
  • Textile washing 
  • Boat antifouling 
  • Litter

In 2019, Naturvårdsverket submitted its second government report on microplastics.

This report identified several additional sources:

  • Spillage and littering around construction sites
  • Equestrian facilities and other outdoor sports and recreational areas with surfaces containing plastic or rubber
  • The use of artificial grass in traffic environments and parks

The main pathways through which microplastics spread in the environment are stormwater runoff, air, and wastewater treatment plants.

To reduce the spread of microplastics in the environment, it has been prohibited in Sweden since 1 July 2018 to sell cosmetic products containing plastic particles with a cleansing, exfoliating, or polishing effect. The ban applies to products intended to be rinsed off or spat out after use on the skin, hair, mucous membranes, or teeth.

Among traffic-related sources of microplastics, road markings are one contributor. On behalf of the Swedish Environmental Protection Agency, the Swedish National Road and Transport Research Institute (VTI) has developed guidance on how procuring authorities and clients can work to reduce this wear and tear (in Swedish).

Sales of microplastics and products containing intentionally added microplastics is being banned in the EU

To reduce the amount of microplastics released into the environment, the European Commission has decided to prohibit the sale of microplastics and chemical products containing intentionally added microplastics within the European Union.

The restriction entered into force on 17 October 2023 and applies to a wide range of products, including plastic granules used in artificial grass fields, cosmetics, paints, cleaning agents, fabric softeners, glitter, plant protection products, and medical devices.

Transitional periods apply to certain uses. For example, a five-year transitional period applies to certain detergents and cleaning products, while an eight-year transitional period applies to plastic granules used in artificial grass fields. For cosmetic products, several different transitional periods apply, ranging from four to twelve years depending on the product category.

More information about the restriction and the microplastic particles covered by it can be found on the Swedish Chemicals Agency's website and in Commission Regulation (EU) 2023/2055, amending Annex XVII to Regulation (EC) No 1907/2006 as regards synthetic polymer microparticles.

Commission regulation (EU) 2023/2055 (eur-lex.europa.eu)

The Swedish Environmental Protection Agency has also presented a number of measures to reduce the spread of microplastics and has proposed introducing a notification requirement for artificial grass fields, playgrounds, running tracks, multi-sport facilities, and other outdoor sports and recreational areas containing rubber or plastic.

It is important to continue working actively at the international level through initiatives such as OSPAR, HELCOM, AMAP, and the EU to promote the development of monitoring, mitigation measures, and policy initiatives, as well as to gain knowledge, experience, and examples of best practice.

It is important to continue working actively at the international level through organizations and frameworks such as OSPAR, HELCOM, AMAP, and the European Union to promote the development of monitoring systems, mitigation measures, policy initiatives, and to facilitate the exchange of knowledge, experience, and best practices.

Water-soluble plastics should be studied further

Water-soluble plastics account for a small but growing share of plastic use. On behalf of the Swedish Environmental Protection Agency, the Royal Institute of Technology (KTH) has compiled current knowledge on water-soluble plastics and their potential environmental impacts. The study concludes that certain types of water-soluble plastics may have negative effects on the environment and that their use should therefore be limited. At the same time, the study recommends further research into water-soluble plastics.

The result is published in a scientific article:

Environmental concerns on water-soluble and biodegradable plastics and their applications – A review (kth.diva-portal.org) 

Environmental concerns on water-soluble and biodegradable plastics and their applications – A review (sciencedirect.com)

More reports about microplastics