Universiteit Leiden

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Rob Overmeer

Mission successful: deposits on small plastic bottles

After years of lobbying by environmental activists, a deposit scheme for small plastic bottles is to be introduced on 1 July 2021. One of the leaders in the fight is alumnus Merijn Tinga. The university will have collection points for plastic bottles and is also supporting the Plastic Spotter citizen science project

A 15-cent deposit has been levied on one-litre plastic bottles for years. But this wasn’t the case for the smaller plastic bottles that are dumped all over the place and pollute the environment. The 15-cent deposit per bottle should change this. Tinga, who studied biology in Leiden, has lobbied passionately for deposits and other strict measures in the battle against plastic litter in a number of spectacular campaigns. Plastic soup surfer Tinga crossed the North Sea on a kiteboard in 2016 and paddleboarded 1,200 kilometres down the Rhine in 2017 to raise awareness of pollution.

Presenting the petition to the Dutch House of Representatives.
Presenting the petition to the Dutch House of Representatives. Photo Eelkje Colmjon

In that same year Tinga opened the academic year in Leiden and called for a sustainable university. He also spoke about at his kiteboarding trip to England, which marked the start of a petition for a deposit scheme for small plastic bottles., which gained almost 60,000 signatures. The proposal was ultimately supported by a majority in the House of Representatives. Tinga and many other activists also lobbied politicians in the Netherlands and Europe, and spoke to business leaders from retail and the packaging industry, urging them to turn the tide. 

Return your bottles to the university

In August 2021 bottle-shaped donation banks for small plastic bottles will be placed at a central spot in the university buildings, close to the waste collection points. Due to demand, the company that provides the donation banks, Statiegeld Nederland, will be unable to supply these banks until August. The university will donate the proceeds from the donation banks to the Plastic Soup Foundation (another organisation than Merijn Tinga’s), which aims to reduce plastic in the water and our bodies, and works closely with scientists. The donation banks are made of recycled plastic. You can also return small deposit bottles to the cafés in the university buildings. As these are cashless, you won’t be able to receive your deposit back, but will instead be able to receive a stamp on a loyalty card (ten stamps equals a free cup of coffee) or have the deposit deducted from the cost of your food or drink. 

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Tap water stations

In autumn 2017 the university installed the first of over 30 tap water stations in its buildings to encourage students and staff to use refillable water bottles. Tinga symbolically opened the first, as can be seen in the You Tube film.

Learnt while studying biology

In previous interviews in the Leidraad alumni magazine and on universiteitleiden.nl, Tinga explained how his biology degree has helped him in the fight against plastic waste. ‘As a biologist I obviously know a lot about marine life. I know how to take samples, what the chemical composition is of plastic and how, for example, a polymer, a component of plastic, looks.’

Cleaning plastic waste from the canals in Leiden.
The Plastic Spotter citizen science project is helping keep Leiden's canals clean.

Plastic spotter

Other Leiden biologists are also active in the fight against plastic waste. In 2019 Auke-Florian Hiemstra and Liselotte Rambonnet started the Plastic Spotter citizen science project. Here the people of Leiden are working with researchers to gain a clear picture of how much plastic waste is floating in the canals of Leiden. The team goes out almost every Sunday to collect plastic from the water. Anyone who is interested is welcome to help. You can also help by spotting plastic waste and sharing this in the Crowdwater app

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