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CML talents receive Stans Award 2024

CML grants three Stans Awards each year, known as the best student thesis, best PhD paper and best outreach from the past year. The CML staff nominated students and colleagues and this year’s jury Prof.dr.ing. Jan Willem Erisman and Prof.dr.ir Willie Peijnenburg made the final decision.

Best student thesis 2023

Juliane Klaura was one of our Master students and he won this years student award. During the awards she briefly introduced us to her thesis: " Animal Lives Embodied in Food Loss and Waste "

Juliane Klaura


Every year, 1.3 billion tonnes of food are lost and wasted globally. Reducing this food loss and waste (FLW) bears benefits for meeting food demand, achieving food security, and can make food systems more sustainable. Assessing current levels of FLW and exploring reduction pathways has thus been recognized as a relevant field of research and policy. Currently, this field emphasizes benefits of FLW reduction for the environment, people, and economy. While this means that the importance of reducing meat loss and waste is recognized based on its high embedded emissions and environmental risks, it also implies that animal welfare remains mostly unaddressed. The suffering and death that is inflicted on animals to produce food that is never eaten remains invisible. Bridging the gap between food waste accounting literature and animal welfare considerations, this thesis estimates animal lives embodied in meat loss and waste of six major meat-producing species along the food supply chain and explores the potential impact of reduction scenarios. It shows that close to 18 billion animal lives were embodied in losses and waste of global meat production and consumption in 2019. Wasted and lost animal lives could be reduced by 7.9 billion if minimal loss scenarios from different regions and supply chain stages were met, and by 4.2 or 8.8 billion if the Sustainable Development Goal 12.3 was implemented to a minimal or full extent. Considering species-specific conscience and sentience, and previous recommendations, the analysis finds leverage points for change at the consumption stage of the supply chain in developed, high-income countries, in Industrialized Asia, judging by absolute, and in North America and Oceania judging by relative numbers, as well as in top countries of FLW and animal life loss. It further identifies trade-offs for animal welfare between reducing FLW of different meat types, especially chicken and beef, and reducing production-based losses while keeping emissions and resource use low and supporting food security.

Best PhD paper 2023

This years winner is Laura Julia Zantis, she won the prize for the paper ‘Nano- and microplastics commonly cause adverse impacts on plants at environmentally relevant levels: A systematic review.‘

Laura Julia Zantis


Over the last years there has been significant research on the presence and effects of plastics in terrestrial systems. Here we summarize current research findings on the effects of nano- and microplastics (NMPs) on terrestrial plants, with the aim to determine patterns of response and sensitive endpoints. We conducted a systematic review (based on 78 studies) on the effects of NMPs on germination, plant growth and biochemical biomarkers. This review highlights that the majority of studies to date have used pristine polystyrene or polyethylene particles, either in a hydroponic or pot-plant setup. Based on these studies we found that effects on plants are widespread. We noted similar responses between and within monocots and dicots to NMPs, except for consistent lower germination seen in dicots exposed to NMPs. During early development, germination and root growth are more strongly affected compared to shoot growth. NMPs induced similar adverse growth effects on plant biomass and length in the most tested plant species (lettuce, wheat, corn, and rice) irrespective of the polymer type and size used. Moreover, biomarker responses were consistent across species; chlorophyll levels were commonly negatively affected, while stress indicators (e.g., ROS or free radicals) and stress respondents (e.g., antioxidant enzymes) were consistently upregulated. In addition, effects were commonly observed at environmentally relevant levels. These findings provide clear evidence that NMPs have wide-ranging impacts on plant performance. However, as most studies have been conducted under highly controlled conditions and with pristine plastics, there is an urgent need to test under more environmentally realistic conditions to ensure the lab-based studies can be extrapolated to the field.

The publication can be found here.

Best outreach 2023

This year Oscar won the Best Outreach prize. He turned his first PhD study into a corporate guide for the responsible adoption of carbon dioxide removal (CDR).

Oscar Rueda

Summary of the publication

Urgent emissions reduction is a must. But achieving net zero by 2050 demands more – it requires additional carbon dioxide removal (CDR) from the atmosphere. Despite the advancements in carbon removals, many businesses are still unsure about the reasons to invest in CDR and are seeking direction on how traditional land-based and innovative technological approaches could fit into their climate action plans.

This business guide provides practical direction for sustainability professionals to develop effective CDR investment strategies. It outlines seven key principles for responsible CDR investments and a decision-making framework empowering companies to evaluate different CDR methods based on company-specific preferences. A complementary excel tool is provided to help companies tailor their own assessments.

Explore the guide to discover a range of promising CDR methods and learn how to proactively plan a diverse portfolio of both nature-based and technological methods, to maximize benefits and minimize risks.

A link to the publication can be found here.

Stans Award

At the initiative of one of the Environmental Science students, Dr. Constance Eikelenboom, an ecotoxicologist then nearing her retirement, in 1986 the CML Students Award is created as a motivational prize for exceptional publications. As Ms. Eikelenboom is known informally as ‘Stans’, it’s soon termed the Stans Award. It’s awarded annually and throughout the years it turned into three prizes, as we know them today: best PhD paper, best student thesis and best outreach from the past year.

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