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First study of its kind investigates microplastics' origin and harmful effects

Photo: Cowi

​A new COWI report demonstrates that microplastics released from society primarily stem from human activity such as car tyres, paint, road strips, shoes and clothes. An unknown amount of the small yet environmentally harmful plastic particles enters the marine environment through our water treatment plants.

Every time we go for a run, paint our house or drive our car, small plastic particles designated as "microplastics" are left in nature, possibly harming organisms and ecosystems.

The significance of the different sources of microplastics found in the environment is still poorly understood. Consequently, the first study of its kind has now been initiated by the Danish Environmental Protection Agency in order to improve the knowledge of sources, effects and the possibilities of reducing microplastics pollution.

Report provides input for future initiatives

In a partnership with Danish and Swedish experts from, e.g., the Technical University of Denmark and IVL Swedish Environmental Research Institute, COWI carried out the study and published the results in a new report. The report establishes that the definition of microplastics, their origin and effects, and where they can be found.

"The report will provide a clearer overview of where to focus efforts, and it constitutes a catalogue displaying ideas for new studies that can be used when planning future initiatives with microplastics," says Chief Specialist in COWI, Carsten Lassen. 

"Among other things, the report shows that microplastics are released through many different daily activities, and that there are several sources to microplastics ending up in the environment. Many effects have been proven on different types of organisms, yet it is still too soon to establish whether or not the releases of microplastics actually pose a risk to the marine environment. Therefore, we need to further investigate what ends up in the water treatment plants so we can get a better understanding of the challenges of microplastics," Lassen ends. 

Great interest in the report

Both Danish and international media have already shown great interest in the report due to the very limited number of previous initiatives examining the actual emissions of microplastics.

The issue of pollution of the oceans with plastics, including microplastics, is not new, but has received increased international attention in recent years. There is a growing concern that pollution with plastics in the long term can have greater effects on the environment than previously assumed.

On the basis of the new report, more investigations are now being planned in order to further establish the harmful effects of the small plastic particles.


By Pernille Bang-Ortmann
Published: 01.12.2015

What are microplastics?

There is no clear definition of microplastics, but in many contexts - and also in COWI's report - microplastics are plastic pieces of a size in the range of one μm to 5 mm.

LAST UPDATED: 23.10.2017