Europe's landscape is dotted with thousands of lakes. The vital freshwater environments they provide for people and wildlife are being celebrated as part of the first ever UN World Lake Day. 

But despite their importance, some of Europe's most treasured lakes are polluted with tiny fragments from plastic bags and synthetic fabrics, according to a LIFE project that has been searching for solutions to this problem.  

The LIFE BLUE LAKES project spent 4 years trying to understand the scale of the challenge caused by microplastics – fragments of plastic less than 5mm in size – at several lakes in Italy and Germany. Pilot monitoring projects at 3 Italian lakes – Bracciano, Trasimeno and Piediluco – over a 2-year period revealed 98 % of water samples were contaminated with plastic particles. In total the project team collected more than 9 000 plastic fragments in the samples. Most came from old plastic bags that break down into ever smaller pieces.  

Researchers on the project also developed methods for monitoring microplastics at 3 drinking water and 2 wastewater treatment plants at Lake Garda near Milan and at Castreccioni near Macerata. They found 30-90 % of microplastics are retained in the treatment process, with the majority coming from polyester and polypropylene clothing.

But the remainder escape into the environment, where they can harm freshwater life in lakes and rivers or pose a risk to human health.  

‘‘We are at a point in history where understanding how to deal with this type of pollution can occur in parallel with the challenge of stopping the phenomenon,’’ says Giorgio Zampetti, director general of Legambiente, an environmental organisation in Italy, and coordinator of the LIFE BLUE LAKES project, which concluded in 2023.