Biotox Lab

10/10/2026

🐟🤖 New paper out in Food Control!

When you buy sea bream at the fish counter, you trust the label. But what if that trust is misplaced?

Seafood mislabelling is one of the most widespread forms of food fraud globally, with studies reporting that nearly 40% of seafood products in some commercial markets misrepresent their origin or production method. For a species like gilthead sea bream (Sparus aurata), one of the most commercially important fish in the Mediterranean and Atlantic markets, the difference between wild-caught and farmed can mean significant price differences, nutritional distinctions, and environmental implications.

In our latest study, we asked: can fatty acids be used as molecular fingerprints to tell wild and farmed sea bream apart? And can machine learning make this scalable?

We analysed the fatty acid profiles of 120 gilthead sea bream collected from wild fisheries and from cage-reared and pond-reared aquaculture systems across the Northeast Atlantic (from mainland Portugal to Madeira Island). We then trained a Random Forest machine learning model to classify specimens by their production group, and used SHAP analysis to identify which fatty acids drove the discrimination.

🤖 99.1% classification accuracy - the model correctly identified wild-caught and farmed sea bream with near-perfect precision, without needing DNA analysis or isotope testing
🔑 Key traceability biomarkers identified - linoleic acid (LA), EPA, palmitic acid and DPA were the most informative fatty acids, with differences likely reflecting dietary inputs and aquafeed formulation across production systems
🫀 All groups are nutritionally valuable - both wild and farmed sea bream are rich in heart-healthy long-chain omega-3 fatty acids EPA and DHA, with a 100g serving contributing meaningfully toward the EFSA-recommended daily intake of 250mg EPA + DHA for cardiovascular health
🌊 Wild fish showed higher relative omega-3 abundance - while cage-reared specimens had higher total lipid content, yielding comparable or greater absolute EPA + DHA per 100g of muscle
♻️ A scalable tool for food integrity - fatty acid profiling coupled with machine learning offers a biologically meaningful, cost-effective framework for seafood authentication that can be progressively expanded across species, markets and supply chains

This work contributes directly to the growing toolkit for seafood traceability in the Portuguese and European markets, supporting food control authorities, producers and consumers in navigating an increasingly complex seafood supply chain.

📄 https://www.sciencedirect.com/science/article/pii/S0956713526007176

Faculdade de Ciências da Universidade de Lisboa
MARE - Centro de Ciências do Mar e do Ambiente
ARNET - Aquatic Research Network
BioISI - Biosystems & Integrative Sciences Institute
Ciimar
Observatório Oceânico da Madeira

27/09/2026

🔬💧 New paper out in the Journal of Xenobiotics!

When we test water for toxic pollutants, we assume our laboratory methods are capturing everything. But what if the contaminants were disappearing right inside the lab, before we even had a chance to measure them?

That is exactly the puzzle we set out to solve in our latest study.

Polycyclic aromatic hydrocarbons (PAHs) are a family of toxic, carcinogenic compounds that enter our rivers, oceans and drinking water from car exhaust, industrial discharges, oil spills and urban runoff. Accurately measuring them at trace levels is essential for environmental monitoring and public health protection. Solid-phase extraction (SPE) is the gold-standard technique for concentrating these compounds from water samples, but something was going wrong.

Despite testing multiple sorbents, elution solvents and extraction protocols, we kept losing compounds. Recovery rates were inconsistent and frustratingly low for the lighter PAHs. Through a systematic, step-by-step investigation, evaluating every stage of the analytical workflow from pre-extraction to post-extraction, we identified the culprit.

Lighter PAH compounds, due to their high vapour pressure, were simply evaporating out of the sample during concentration, escaping the vial before ever reaching the detector. No sorbent change or solvent switch could fix a problem happening after the extraction itself.

The solution was elegant: a two-stage evaporation approach partially concentrating the dichloromethane extract under nitrogen, addition of acetonitrile as a transient stabiliser, and re-evaporating to a small volume. By never evaporating to complete dryness and using acetonitrile as a high-boiling-point keeper, volatile PAHs were retained in the liquid phase throughout.

The results speak for themselves:

✅ Recoveries of 72–110% across all 18 target PAHs
📊 RSD below 10% — excellent reproducibility across all water matrices
🌊 25 real water samples successfully analysed — ocean water, river water, WWTP effluent and influent — all from Portugal
🏆 Method validated across the full complexity spectrum, from drinking water to raw wastewater, with all detected concentrations below EU regulatory limits

This work fills a critical gap in environmental analytical chemistry and provides a robust, validated tool for monitoring PAH contamination in aquatic ecosystems. Accurate detection is the first step toward effective management — and this method makes that detection possible.

📄 https://www.mdpi.com/2039-4713/16/6/186



Faculdade de Ciências da Universidade de Lisboa
MARE - Centro de Ciências do Mar e do Ambiente
ARNET - Aquatic Research Network
Associated Laboratory for Green Chemistry
ISEP - Instituto Superior de Engenharia do Porto

25/09/2026

Noite Europeia dos Investigadores 2026 | European Researchers Night 2026

Hoje no Pavilhão do Conhecimento - Centro Ciência Viva! Venham visitar-nos!

Today at the Pavilhão do Conhecimento - Centro Ciência Viva! Come to visit us!

Faculdade de Ciências da Universidade de Lisboa
MARE - Centro de Ciências do Mar e do Ambiente
ARNET - Aquatic Research Network

17/09/2026

🦠🌊 Happy International Microorganism Day — and why the ocean's microbes matter for your health too!

Today, on International Microorganism Day, we want to highlight a connection that is often overlooked: the link between marine microbial health and human health.

The One Health framework recognises that human, animal and ecosystem health are deeply interconnected. And marine microorganisms, such as bacteria, fungi and countless other microscopic life forms, sit right at the heart of this web.

When our oceans are healthy, their microbial communities thrive. When they are polluted, the consequences don't stay in the water, they reach our plates, our bodies, and our medicines.

Here's why marine microorganisms matter beyond the ocean:

🧹 Nature's cleanup crew — Marine bacteria are remarkably capable of breaking down organic pollutants, heavy metals and pharmaceutical residues that enter the ocean through wastewater and agricultural runoff. They are our first line of defence against environmental contamination

⚠️ The antibiotic resistance threat — Contaminants can drive the emergence of antibiotic-resistant bacteria in marine environments. These resistant strains don't stay in the sea: they can be transmitted to humans through seafood consumption, creating a silent but serious public health threat that demands urgent attention

🍽️ Seafood safety — Marine microbiomes directly shape the safety of the seafood we eat. The microbial communities living in and around shellfish, fish and other marine organisms are deeply influenced by the health of the surrounding ecosystem. Stressed, contaminated ecosystems breed microbial communities that put food safety at risk

🌍 A One Health imperative — Protecting the health of our ocean's microbial communities is not just an environmental priority, it is a public health priority!

What happens in the ocean does not stay in the ocean!

At MARE - Centro de Ciências do Mar e do Ambiente / ARNET - Aquatic Research Network, Faculdade de Ciências da Universidade de Lisboa understanding the role of marine microorganisms in ecosystem functioning, contaminant dynamics and human health is a central pillar of our research through the BIOTOX group. Because healthy oceans mean healthy people. 🌊

17/09/2026

🦠🌊 Happy International Microorganism Day!

Today we celebrate the smallest — and arguably most important — forms of life on our planet. And in our group, that means celebrating the ocean's invisible workforce.

Marine microorganisms — bacteria, fungi, and countless other microscopic life forms — make up over 90% of all ocean biomass. They produce roughly half of the oxygen we breathe, regulate global nutrient cycles, decompose organic matter, and form the invisible foundation upon which all marine life depends. Yet they remain among the least understood components of ocean ecosystems.

At the Biotox Lab (MARE - Centro de Ciências do Mar e do Ambiente/ ARNET - Aquatic Research Network), studying marine microorganisms is at the heart of much of what we do:

🌿 Ecosystem health & restoration — Marine bacteria and fungi are key drivers of habitat recovery. From salt marsh restoration to blue carbon ecosystems, microbiomes underpin the resilience and functioning of coastal habitats we are working to protect

💊 Biotechnological potential — Marine microorganisms are an extraordinary reservoir of bioactive compounds — natural antibiotics, antifungals, enzymes and metabolites with transformative applications in medicine, sustainable agriculture and industry. Much of this potential remains untapped

🔬 The Marbiome Biobank — Our marine microbial culture collection preserves living diversity from coastal blue carbon ecosystems, making it available for research, conservation and innovation. Culture collections like Marbiome are essential infrastructure — they safeguard microbial heritage and enable science that would otherwise be impossible

🧬 The bigger picture — Understanding and protecting marine microbiome diversity is not just a scientific priority. It is fundamental to ocean restoration, climate resilience and the long-term health of our blue planet.

On this International Microorganism Day, we invite you to look beyond what the eye can see — because in the ocean, the smallest things make the biggest difference. 🌍



Faculdade de Ciências da Universidade de Lisboa

12/09/2026

🌊🌿 New paper out in Plant Science!

What if the solution to one of agriculture's most devastating diseases was washing up on our beaches?

Tomato late blight, caused by Phytophthora infestans, is one of the most destructive crop pathogens in history. It triggered the Irish Famine in the 19th century and continues to devastate tomato and potato crops worldwide, costing billions annually. Current control strategies rely heavily on chemical fungicides with well-documented environmental and human health impacts. We urgently need sustainable alternatives.

In our latest study, we explored the potential of two invasive seaweeds, Asparagopsis armata and Sargassum muticum, as natural biocontrol agents against P. infestans in tomato plants.

Here's what we found:
🛡️ Both seaweed extracts acted as effective biocontrol agents — protecting tomato plants against Phytophthora infestans infection by boosting the plant's own immune defences
⚡ Key physiological pathways were activated — including photochemical energy distribution, membrane lipid composition, redox balance, and secondary metabolism, all contributing to enhanced plant resilience
🌿 Asparagopsis armata showed particularly strong effects — eliciting a powerful defence response that was directly correlated with improved outcomes during pathogen infection
🔄 Sargassum muticum induced moderate but consistent effects across multiple defence pathways, confirming its potential as a complementary biocontrol tool
♻️ A truly circular solution — both species are invasive along European coastlines, causing significant ecological damage. Valorising their biomass as crop-protection agents turns an environmental problem into a sustainable resource

This work provides important physiological insights into how marine macroalgae can simultaneously suppress pathogen activity and prime plant immunity, opening exciting new avenues for sustainable, marine-derived agricultural inputs.

📄 Laureano G., Fonseca B., Carreiras J.A., Felix C., Lemos M.F.L., Figueiredo A., Duarte B. (2026). From Sea to Farm: Repurposing Invasive Macroalgae into Biocidal and Defense-Enhancing Tools Against Tomato Late Blight (Phytophthora infestans). Plant Science.

https://www.sciencedirect.com/science/article/pii/S0168945226004735

Faculdade de Ciências da Universidade de Lisboa
Escola de Turismo e Tecnologia do Mar - Universidade de Leiria e Oeste
MARE - Centro de Ciências do Mar e do Ambiente
Cetemares MARE Politécnico de Leiria
ARNET - Aquatic Research Network
BioISI - Biosystems & Integrative Sciences Institute
Grapevine Pathogen Systems Lab

12/08/2026

🎙️ New Episode | BIOTOX Deep Dive Podcast

In Episode 5, we explore an emerging environmental issue at the intersection of public health, environmental chemistry and marine ecology.

Using long-term Portuguese wastewater monitoring as a starting point, we discuss how changing patterns of illicit drug consumption are reflected in rivers and estuaries, and what these trends may mean for aquatic organisms. The episode addresses co***ne, M**A, ketamine and methamphetamine, their passage through wastewater treatment systems, and their potential biological consequences for fish, bivalves and other estuarine organisms.

The discussion also highlights the need to move beyond monitoring what enters wastewater treatment plants and towards understanding what actually reaches the estuary, accumulates in organisms and affects ecosystem functioning.
Produced using recent AI-assisted audio and storytelling technologies, this episode continues our effort to make environmental science accessible beyond the scientific community.

🌐 Full BIOTOX Deep Dive collection:
https://biotoxlab.wixsite.com/home/podcasts

🎧 Episode 5:
🇵🇹 https://open.spotify.com/episode/7e87w4zDEnRfTAiRXyBk1o?si=UAhciRPKSly1XlPi5gAnGQ
🇬🇧 https://open.spotify.com/episode/63rFtB0Sk7Mmx15LfZc8wF?si=AQHSxsz2S_u0g7vq0sstBA



Faculdade de Ciências da Universidade de Lisboa
MARE - Centro de Ciências do Mar e do Ambiente
ARNET - Aquatic Research Network

Deep Dive BIOTOX · Episode

08/08/2026

🌿 Exciting news — RENATURE has been approved for funding under MAR2030!

We are thrilled to announce that our project RENATURE — Restoration of salt marshes affected by invasive plants using innovative nature-based solutions has been approved for funding under the MAR2030 programme, in the call for "Support for the Protection and Restoration of Biodiversity and Marine Ecosystems".

Salt marshes are among the most productive and valuable ecosystems on the planet — estimated to provide €3.8 trillion in ecosystem services annually, including coastal protection, carbon sequestration, water filtration, and nursery habitat for commercially important fish and shellfish species.

Yet across Mediterranean and Atlantic coastlines, these habitats are being rapidly taken over by an invasive plant: Spartina patens. So how do we fight back? With nature itself. Spartina patens depends critically on arbuscular mycorrhizal fungi in the soil to establish, spread, and survive. Disrupt that fungal partnership — and the plant retreats.

RENATURE will harness the natural antifungal properties of invasive seaweeds — including Asparagopsis armata — which wash up in abundance on our coasts, to develop biocontrol extracts capable of eliminating S. patens from affected salt marsh areas. In doing so, we turn one invasive species into a tool to fight another — a truly circular, nature-based solution.

The project's key objectives include:
🔬 Characterising the bioactive compounds in invasive seaweed biomass with antifungal potential
🌱 Understanding the Spartina patens–mycorrhizal fungi system and its vulnerability to disruption
🧪 Testing seaweed-based biocontrol extracts under controlled and field conditions
🐟 Assessing the recovery of endemic salt marsh vegetation, fauna, and ecosystem services
📊 Quantifying the socioeconomic benefits of restored salt marsh for fisheries and aquaculture

RENATURE is a collaborative effort between the Faculdade de Ciências da Universidade de Lisboa, Escola Superior de Turismo e Tecnologia do Mar - Politécnico de Leiria, MARE - Centro de Ciências do Mar e do Ambiente, ARNET - Aquatic Research Network, BioISI - Biosystems & Integrative Sciences Institute, Centre for Ecology, Evolution and Environmental Changes - ce3c and CHANGE - Global Change and Sustainability Institute, bringing together expertise in marine ecology, plant physiology, microbiology, and ecotoxicology.

We look forward to sharing our progress as this exciting project gets underway. Stay tuned! 🌊

25/06/2026

"Quais os conceitos-chave para enfrentar os atuais desafios marinhos e costeiros?" é o tema central da Escola de Verão redeMAR ULisboa 2026, que terá lugar entre os dias 13 e 17 de julho de 2026.

03/06/2026

🌊 We’ve signed the Manifesto de Vila Nova de Milfontes — and I believe every marine scientist in Portugal should too.

Last month, researchers, civil society organisations, coastal communities and businesses gathered in Vila Nova de Milfontes for the IV Festival das Florestas Marinhas. What came out of it was more than a meeting: it was a collective declaration of urgency.

Portugal’s marine forests — seagrass meadows, kelp and macroalgae forests, coral and sponge gardens, biogenic reefs — are degrading. Often silently. Often without the monitoring systems needed to even measure the scale of the loss. These are not peripheral habitats. They are the nurseries of our fisheries, the buffers of our coastlines, the filters of our water, the carbon stores of our ocean.

The Manifesto calls for six concrete steps: formal recognition of marine forests as strategic national infrastructure; a National Strategy for Marine Ecosystems to 2040 with measurable targets; effective protection of coastal and oceanic habitats; a national long-term monitoring and mapping programme; ocean literacy investment; and integration of sustainable blue bioeconomy models.

None of this is radical. All of it is urgent.

The evidence base for action exists. What has been lacking is political will and structural commitment. This Manifesto — signed by nearly 80 researchers, institutions, organisations and citizens, and submitted to the President of the Republic, the Government and Parliament — is an attempt to change that.

If you work in marine science, conservation, policy or ocean stewardship in Portugal, we encourage you to read and sign it.

🔗 https://filesender.fccn.pt/?s=download&token=f59bcd46-a466-40eb-82f0-7cbe6f20b87b



Faculdade de Ciências da Universidade de Lisboa
MARE - Centro de Ciências do Mar e do Ambiente
ARNET - Aquatic Research Network