What do bats do at night when they’re not hunting? Using tiny GPS trackers, Leiden researchers discovered that pond bats spend a substantial portion of the night resting – often outdoors. This surprising insight could change the way we protect them.

Promotor: M.L. van Hecke

The Leiden Advocacy Project on Plastic (LAPP) is a pro bono initiative concerning legal questions on plastics and is founded to address and research the legal issues related to plastic pollution.

Promotor: P.M. Brakefield

Environmental challenges such as plastic pollution and biodiversity loss require extensive monitoring. Citizen science, in which members of the public participate in scientific research, has therefore become an important approach in environmental science.

In light of climate change, it is crucial to determine whether plant species can adapt to future climates to avoid extinction. Plants adapt to various conditions by altering their functional traits, such as leaf size or photosynthetic rate. Some traits appear linked and vary together between species,…

Plastics have become an integral part of modern society due to their versatility and durability.

Leiden PhD candidate Jo-Anne Verschoor discovered that nearly twenty percent of the bacterial strains she studied could degrade plastic, though they needed some encouragement to do so. ‘Bacteria are just like people,’ says Verschoor. Her research was published in the journal Communications Biology,…

Cookware handles, electrical plugs, brake pads. Unlike other plastics, these ‘thermosets’ cannot simply be melted down and reshaped, making them difficult to recycle. Chemist Roxanne Kieltyka and her team are now exploring a way to make these materials recyclable, potentially transforming the way we…

Help us spot and clean up the plastic in the canals of Leiden! Leiden University is calling on the good folk of Leiden to help our researchers study the plastic in the city’s canals. And if you’d like our canals to be plastic-free, why not donate towards a fleet of canoes to clean them up?

The Plastic Soup Foundation and Parley for the Oceans hosted the very first Plastic Heath Summit in Amsterdam on 3 October, covering the most relevant and pressing health concerns surrounding plastics and human health. Beyond discussing the latest findings in the field we asked the urgent question:…

Plastic pollution is a major environmental issue. Although regulation is being adopted, plastic pollution is still increasing. Effective and strict enforcement is key and NGOs and civilians can be instrumental in this.

For many system in statistical physics the microcanonical and canonical ensemble are equivalent in the thermodynamic limit, but not for all.

The sand on European beaches may look pristine, but in every kilogram of sand there are on average 250 microplastics: fragments smaller than 5mm. These results are part of a study from Leiden researchers with the help of beach-goers throughout Europe.

On Friday 8 February, the first Plastic Avengers Conference took place in Amsterdam. Initiator Merijn Tinga, the Plastic Soup Surfer from Leiden, brought together ‘independent plastic fighters' to arrive at a manifesto against plastic pollution. The Leiden Advocacy Project on Plastic was also invited…

Promotores: Prof.dr. P.M. Brakefield, Prof.dr. B.J. Zwaan (Wageningen Universiteit)

Merijn Tinga, the Plastic Soup Surfer, launched the Pick Up 10 campaign. This campaign, supported by Google and National Geographic, uses photo recognition to identify and monitor litter through an app.

From 3 to 13 December you can see the exhibition Plastic Justice at the Kamerlingh Onnes Building. Esther Kentin, coördinator of the Leiden Advocacy Project on Plastic, saw the exhibition at the Plastic Health Summit and initiated a collaboration with the Royal Academy of Art in The Hague.

With this thesis the PhD-candidate aims to enrich the body of evidence concerning the relation between stress and health, and the mediating role of (un)conscious perseverative cognitions, which is captured in the extended perseverative cognition hypothesis.

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…

FFashion, particularly fast fashion, is a major contributor to plastic pollution in the form of microplastic fibres. The 80-year-old Martindale test for interior textiles could be part of the solution.

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Two weeks after 3 October the Leiden canals were still full of plastic disposable cups. Auke-Florian Hiemstra and fellow students have fished thousands of these cups out of the canals and photographed them. Now they put a photo of one of these canal cups on Instagram every day.

Enhancing social inclusion through developing methods and analytical tools for understanding and reasoning about such phenomena based on sensor data.

On paper it is recycled, but in reality enormous quantities of plastic waste from the Netherlands end up in Asian seas. Researchers from the Leiden Institute of Environmental Sciences charted the fate of plastic food packaging waste from the Netherlands. They published their results on July 8 in the…

'We have to look for products that can replace ordinary disposable plastics, for example of organic material. Within 20 years, the average plastic use of a household will be largely reduced.' According to Thijs Bosker, Associate Professor at Leiden University College, in Edition NL of Tuesday, October…

Plastic pollution is a major global problem. In Geneva, world leaders are discussing a possible plastics treaty. Lecturer Esther Kentin talked to Dutch news platform NU.nl about the UN summit: ‘A treaty is only a small part of the solution.’

This is the team of LAPP:

Roberto Arciero is part of RESPIRE project (Research Educational and Storytelling Project in Italian Remote Ecosystem), an international and interdisciplinary research team led by Martina Capriotti (University of Camerino) that received the National Geographic Meridian grant. Among the different topics,…

Nanoplastics influence the behaviour of larval zebrafish, says new research by the Institute of Biology Leiden (IBL) and the Institute of Environmental Sciences (CML). The researchers observed that a certain type of nanoparticles leads to stress reactions in the sugar balance, resulting in hyperactivity…

Piecing together the urnfield mortuary process in the Lower-Rhine-Basin, ca. 1300 - 400 BC

A group of biology students are working on a solution to the world’s plastics problem by getting bacteria to make biodegradable plastic.

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.

From researching plastic pollution to caring for injured wildlife, volunteers play a crucial role in conservation. But much of the valuable knowledge they gather remains unused.

Engineering an efficient microbial enzymatic polyethylene degradation pathway via an innovative combination of biochemistry and computational biology tools for enzyme discovery and characterization.

Plastic pollution is a major global problem. In Geneva, world leaders are discussing a possible plastics treaty. Lecturer Esther Kentin talked to Dutch news platform NU.nl about the UN summit: ‘A treaty is only a small part of the solution.’

What is the influence of the 2016 ban on free plastic bags on the environment? Industrial ecologist Stefano Cucurachi received a LUF grant of €75.000 to answer this question.

This thesis explores Breaking of Ensemble Equivalence (BEE) in random graph models by examining the spectral properties of adjacency matrices. The goal is to identify spectral characteristics that differentiate random graph ensembles, enhancing the understanding of complex network structures and beh…

In this thesis, we have used numerical approaches to study the effects of translational symmetry breaking on strange metallic systems as realised by the holographic duality⁠.

From 27 to 31 January, a workshop on the regulation of plastic pollution based on scientific evidence will be held at the Lorentz Center in Leiden.

In what ways can mental health care policy and interventions help break the cycle of mutually reinforcing societal stressors and mental health problems in Burundi?

Biologist, artist, activist and Leiden alumnus Merijn Tinga supped the river Rijn in 28 days, to gain attention for plastic waste. His journey of more than 1000 kilometers has been captured in the documentary ‘From Source to Sea’, that can be seen on 4 June at 20:50 on National Geographic Channel.

On Friday 8 February, the first Plastic Avengers Conference took place in Amsterdam. Initiator Merijn Tinga, the Plastic Soup Surfer from Leiden, brought together ‘independent plastic fighters' to arrive at a manifesto against plastic pollution. The Leiden Advocacy Project on Plastic was also invited…

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…

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.’

What motivates citizens to participate in a citizen science project on plastic pollution? And does that motivation change over time? Liselotte Rambonnet tried to answer these and other questions with her research on the Clean Rivers (‘Schone Rivieren’) project. Rambonnet is a PhD student at the Institute…

On 3 May2017 LAPP participated in a meeting on microplastics at the Plastic Soup Foundation.

The Copenhagen interpretation of quantum mechanics states that a measurement collapses a wavefunction onto an eigenstate of the corresponding measurement operator.