Every Sunday you can help fish plastic and other floating garbage out of the Leiden canals. You can use your own canoe or loan one from Plastic Spotter and join the garbage-fishing fleet. Annetje Ottow, President of Leiden University, was one of the crew on Sunday 4 July.

Shell, our country's largest company, is constructing a vast plastics plant in the United States. And it is doing so at a time when the European Union, led by the Netherlands, is launching a major pact to combat use of plastic.

At the recent UN summit in Geneva, representatives from more than 180 countries failed to reach a global plastics agreement. Esther Kentin, a lecturer at Leiden Law School, spoke to media outlets on the issue: ‘Human health is at stake.’

On Friday evening 8 June, Thijs Bosker, Associate Professor at Leiden University College (LUC), was on television in NOS Jeugdjournaal about plastic pollution and microplastics

After studying medicine in Leiden, Diederik Hofstede specialised in plastic surgery. 'I was attracted by its creativity and I enjoy working with my hands.' Cosmetic surgery is just 5% of the work.'

Heterogeneous catalysis is essential to many industrial applications. These catalysts are often comprised of supported nanoparticles, which contain various different surface sites.

On Friday morning, 8 June, Thijs Bosker, Associate Professor at Leiden University College, was interviewed by NPO Radio 1 on plastic pollution in Antartctica: ''Anually, an additional 4 - 12 billion kilos of plastic ends up in our ocean''.

Getting started with active learning & teaching can be as simple as assessing on what is already accomplished. Here are some practical courses of action to begin experimenting with active learning, whether you are a teacher or responsible for the spaces.

One person can already make a difference, and if all students and academics were eco-friendly, the world would be a much more sustainable place. Plastic Soup Surfer Merijn Tinga opened the academic year in Leiden with this message.

Whales in the vicinity of the city of Auckland, New Zealand consume large amounts of microplastics every day. A team of international researchers reached this conclusion after carefully examining whale poop. The team included Thijs Bosker, Associate Professor in Environmental Sciences at Leiden University…

This year will see the start of not one but two citizen science projects in Leiden and The Hague. This is the outcome of a large survey among residents and researchers in both university cities. The Citizen Science Lab will help the winners implement their ideas, with support from the University and…

It's now possible to measure how many plastic particles there are in our food. Chinese scientists and Leiden professor Willie Peijnenburg applied their new method to lettuce and wheat. Their results were published January 20 in Nature Nanotechnology.

International trade has played a major role in defining the modern global economy. Trade, however, entangles the environmental pressures of economic sectors, giving the illusion of environmental improvements, while the opposite may be occurring.

Micro- and nanoplastics cause stress to crops such as lettuce and carrots, PhD candidate Laura Julia Zantis found. This can lead to reduced growth and a lower nutritional value. Biodegradable plastics have this effect too, likely because of chemicals they release during degradation.

Martin van Hecke en Anne Meeussen publiceren in het tijdschrift Nature over mechanische metamaterialen. Ze hebben een nieuwe klasse multistabiele materialen ontdekt. Dit is gebaseerd op ribbeltjes plastic.

Countries that import plastic waste recycle an average of at least 63 percent of it. This is surprising, as we previously believed that the vast majority was incinerated or ended up as litter. This was discovered by PhD candidate Kai Li and his colleagues from the Institute of Environmental Sciences in…

Leiden researchers have discovered an enzyme that helps bacteria feed on everyday plastics. This common enzyme could play a crucial role in future research and eventually in addressing the global plastic crisis. The study was published in Nature Communications.

Jo-Anne Verschoor wins the Unilever Research Prize 2020. The master's student in Biology developed a method to test whether bacteria are capable of degrading plastic. Verschoor: 'Using specific enzymes from these bacteria, we may be able to efficiently recycle plastic in the future.

The last blog of Leiden Law Blog of 2018 was written by Ladislav Kováč. He discusses the proposal for the Single-use Plastics Directive of the EU which was agreed upon on 19 December.

Schuurman examines how Russia is escalating its covert operations against European countries.

Nano-plastics cause malformations. Meiru Wang, researcher at the Institute of Biology Leiden, looked at the extreme effects polystyrene nano-particles could have, using chicken embryos as a model. Her results were quite alarming. Especially as nano-particles are everywhere. In the air, floating through…

When you have finished your dissertation, it is time to prepare for the defence procedure.

LAPP student Heidi Kaarto and project leader Esther Kentin published an article on the right to regulate in relation to an EU ban on microplastics in a special issue on plastic regulation of Review of European, Comparative & International Environmental Law.

A team of students from Leiden and Groningen took the second prize at the European final of the BISC-E sustainability competition. Last June, the team had already won the Dutch finals. The students came up with ‘Suckerspheres’, a natural alternative to the plastic micro-particles that are still frequently…

Leiden Law Cast is a podcast made by Leiden Law School, Leiden University, for everyone who wants to learn more about current legal issues.

Recycling of post consumer plastic waste is problematic in that the environmental benefits are questionable and the costs are significant. It would be better to separately collect the most useful parts through the expansion of the deposit system.

This article presents a five-step framework for building behavioural cybersecurity strategy to reduce human-related risks affecting organisational security

What looked like an ordinary coot’s nest turned out to be a five-star location with a remarkable backstory. Beneath a jetty on the Rokin in Amsterdam, biologist Auke-Florian Hiemstra discovered a true time capsule — complete with face masks from the COVID era and a Mars wrapper dating back to the 1994…

Promotores: Prof.dr. H.S. Overkleeft, Prof.dr. G.A. van der Marel

The analysis of protein residues extracted from the storage containers of circa 50,000 year old bone-tools reveals Neandertal strategic selection of bovid ribs to make some of their “lissoirs”.

In the Port of Rotterdam, tiny industrial pellets leak into the environment, causing a form of pollution that’s hard to trace but highly persistent. Three students of the LDE Sustainability Honours Programme took on the challenge to identify sources of this pollution.

The aim of this project is to develop, evaluate, and multicentre implement a blended form of cardiac rehabilitation that uses a theory-based approach to guide patients to full self-management.

In recent years, the use of primary data in terrorism research has increased. In order to maximise the benefits of this trend, we want to encourage terrorism scholars to implement open science practices more systematically. This article therefore presents different avenues towards open and reproducible…

On 28 November 2025, Leiden University and PLNT Leiden will host “The Knowledge Orchard” - an event aimed at starting up/ enhancing interdisciplinary cooperation between academics at Leiden University, and improving collaboration between Leiden researchers and external partners in research and educa…

Supervisor: Indira Nederpelt

An image has great powers of persuasion. It is said that ‘a picture is worth more than a thousand words’. But these days, images can easily be manipulated with severe consequences. ‘Perhaps it’s time to reconsider the value we attach to images’, says Elize de Mul, whose PhD thesis deals with ‘digital…

Lecture, Studium Generale

Promotor: Prof.dr. M.K. Richardson, Co-Promotor: F. Witte

Current clients

The Grachtwacht (Canal Watch) conducts research on urban wildlife and the impact of plastic on nature. With our clean-ups, we not only collect waste, but also data. This way we try to find out the source of the waste and turn off the tap on shore. This way there is structurally less plastic in the c…

Below you will find an overview of the publications of The Leiden Advocacy Project on Plastic.

Former clients en projects

This week, the cooperation between the Zwerfinator and Leiden University was in the news because of loose labels on deposit bottles. NOS news reported that the Zwerfinator submitted an enforcement request to the Inspectorate. The Leiden Advocacy Project on Plastic (LAPP) is supporting litter waste expert…