The Hidden Chemicals Sabotaging Our Health
In a world steeped in synthetic chemicals, a silent disruption within our bodies is fueling a public health crisis. The NEMESIS project is fighting back.
Duration: 2024-2028 (5 years)
Funding: €8 million
Partners: 14 institutions
Scope: European initiative
Imagine a hidden trigger for some of the world's most pervasive health problems—like type 2 diabetes and fatty liver disease—lurking in our everyday environment. This is the alarming reality of metabolism-disrupting chemicals (MDCs), and a major European research initiative, the NEMESIS project, is on a scientific quest to expose them 2 3 .
For decades, the focus on harmful chemicals has often been on their potential to cause cancer. However, a growing body of evidence points to a more insidious threat: many common chemicals can interfere with our bodies' fundamental metabolic processes 3 .
These MDCs are found in a wide array of consumer products, leading to unavoidable, continuous exposure 2 . The NEMESIS project was launched in January 2024 with a clear mission: to uncover how these exposures are linked to adverse health outcomes and to develop novel tools—biomarkers—to detect their effects before full-blown disease develops 1 4 .
Metabolism is the complex set of life-sustaining chemical reactions that convert food into energy and building blocks for our cells. Metabolic disruptors are foreign chemicals that can hijack these delicate processes.
To tackle this multifaceted challenge, the NEMESIS project has assembled a diverse consortium of 14 partner institutions from across Europe, coordinated by Professor Jaana Rysä from the University of Eastern Finland 1 4 . The project, which will run for five years until the end of 2028, is funded by the European Union's Horizon Europe programme with a grant of nearly €8 million 4 5 .
Led by Tim Nawrot. Analyzes biomonitoring data to measure MDC levels in European populations.
Investigates effects of MDCs in liver (WP3), pancreas (WP4), and gut microbiota (WP5).
Led by Jukka Hakkola. Uses mammalian and non-mammalian models to study exposure outcomes.
Leader Vittorio Fortino. Uses computational tools to integrate data and predict exposure outcomes.
Spearheaded by Susana Viegas. Translates findings into risk assessment and policy advice.
One of the most visually compelling aspects of the NEMESIS research involves the use of zebrafish as a model organism to study the metabolic effects of MDCs. In October 2024, researchers at the Wincent Lab at Karolinska Institutet began a crucial series of experiments 8 .
The experimental process is designed to mimic real-world exposure scenarios, particularly during vulnerable early life stages.
The team selected eight suspected metabolic disruptors for testing. Zebrafish embryos were exposed to these chemicals to assess their immediate toxicity and impact on early development over five days 8 .
Researchers established the specific concentrations of each chemical that cause adverse effects on embryo development. This critical step ensures that subsequent experiments use relevant exposure levels to investigate longer-term consequences 8 .
After the initial embryonic exposure, the zebrafish were raised without further chemical treatment. The researchers then monitored them during their juvenile stages, up to 30 days post-fertilization, to see if the brief early-life exposure had latent metabolic or transcriptomic (gene expression) effects 8 .
The team plans to compare these results with effects from chronic exposure in adult zebrafish, both with and without the added stress of a high-fat diet 8 .
Zebrafish are a powerful model for this research because they share a surprising 70% of their genes with humans, and their metabolic pathways are highly conserved. They develop rapidly, are transparent for easy observation, and are highly sensitive to environmental changes, making them an ideal "canary in the coal mine" for metabolic disruption 8 .
| Chemical Code | Tested Concentration Range | Effect on Survival (at 5 dpf) |
|---|---|---|
| MDC-A | 1-100 µM | Significant reduction at 50µM |
| MDC-B | 0.1-50 µM | No effect |
| MDC-C | 5-200 µM | Reduction at 100µM |
dpf = days post-fertilization; Data is illustrative based on described methodology 8 .
| Parameter Measured | Method of Analysis | Significance |
|---|---|---|
| Lipid Accumulation | Oil Red O Staining | Indicator of steatotic (fatty liver) disease |
| Glucose Levels | Whole-body assay | Indicator of glucose metabolism disruption |
| Gene Expression | RNA Sequencing | Reveals changes in metabolic pathways |
The NEMESIS project employs a battery of New Approach Methodologies (NAMs) to move beyond traditional toxicology and gain a more comprehensive understanding of MDCs 5 . The following toolkit outlines some of the essential resources and methods central to this groundbreaking work.
| Tool / Method | Function in NEMESIS Research |
|---|---|
| Human Cohort Datasets | Provide real-world data on chemical exposure levels and associated health outcomes across different populations 2 3 . |
| In-Vitro Models | State-of-the-art cell cultures (e.g., of human liver, pancreas) are used to study specific mechanisms of chemical disruption in a controlled environment 3 5 . |
| Zebrafish Model | A whole-organism model to study adverse metabolic outcomes and associated mechanisms during early development and in response to chronic exposure 8 . |
| Mouse Model | Used in parallel with zebrafish to compare adverse effects and validate findings in a mammalian system 8 . |
| Multi-Omics Analysis | A systems biology approach integrating data from genomics, transcriptomics, etc., to discover predictive biomarkers and understand complex biological responses 5 9 . |
| In-Silico & Computational Tools | Leverage models and simulations to predict the risks of chemical mixtures and identify novel biomarker signatures 4 6 . |
| Mixture Risk Assessment (Mixture RA) | A framework to evaluate the cumulative risks posed by multiple chemicals acting together, reflecting real-world exposure 6 . |
The ultimate goal of NEMESIS is not merely to publish academic papers but to translate scientific evidence into tangible public health benefits. A key part of this is addressing the "mixture problem." As noted in a recent NEMESIS report, we are not exposed to chemicals in isolation but to complex mixtures, and the combined effect can be greater than the sum of its parts 6 .
The project is actively developing and applying Mixture Risk Assessment to evaluate these cumulative risks, pushing for regulatory frameworks that better reflect reality 6 . Furthermore, through its dedicated policy and outreach work package, the consortium ensures that its findings on novel biomarkers and health impacts are communicated to risk assessors, policymakers, and citizens 4 .
The aim is to empower people with knowledge to make healthier choices and to build the scientific foundation for stricter regulations on harmful metabolic disruptors.
Project launch & initial experiments
Data collection & biomarker development
Policy recommendations formulation
Final reporting & implementation strategy
The journey of the NEMESIS project is a testament to the power of collaborative science. By uniting experts from toxicology, medicine, computational biology, and social sciences, the project is forging a new path in the detection and understanding of metabolic disruptors 1 . From the precise molecular work in test tubes to the observation of whole zebrafish, and finally to the analysis of large-scale human data, every piece of the puzzle brings us closer to unmasking these hidden saboteurs.
The development of novel biomarkers will be a revolutionary step, allowing for earlier detection of chemical-induced metabolic disruption and more effective, preventative risk assessment of chemicals 2 5 . As this five-year mission continues, its findings promise to shine a light on the invisible threats in our environment, guiding us toward a future where public health is proactively protected.