The main objectives of the Ecotoxicology group are six-fold:
- Development of mechanistic approaches to model and describe effects of different types of enviromental stressors in organisms.
- Development and application of a multi-biomarker approach for aquatic monitoring in a multi-pollution context. Three sets of biological responses concerning (i) genotoxicity, (ii) oxidative stress and (iii) endocrine alterations are adopted by using a strategy integrating multilevel biological endpoints in aquatic organisms.
- Study of metal accumulation and biochemical responses (xenobiotic biotransformation, peroxidative damage and antioxidants) in aquatic organisms belonging to three different trophic levels (macroalgae, benthic crustacean, and fish) in order to assess the specific pattern of response to the co-occurrence of eutrophication and moderate metals contamination in coastal ecosystems, as well as to determine which can better reflect the environmental health status.
- Assessment of the suitability of toxicity parameters associated with pesticides, derived in temperate climates, for Ecological Risk Assessment in tropical conditions.
- Assessment of the ecological risk associated to the presence of environmental endocrine disruptors derived from biocides used in ship antifouling paints along the Portuguese coast and the development of new methodologies for spatial and temporal monitoring of this pollution.
- Utilization of European Ecological Risk Assessment schemes for contaminated sites (abandoned mine areas), in order to improve quantity and quality of data gathered and also a progressive reduction in the uncertainty of the evaluations.
- Understand how alien fish and mollusc species interact with the native species, in order to fully comprehend their impacts and interactions with other environmental stressors and to propose future mitigation measures.
To attain the defined objectives, future investigation will be developed in order to:
- Monitor the levels and biological effects of a variety of endocrine disruptors (e.g., organotins, phenolic compounds, effluent discharged steroids) along the Portuguese coast.
- Improve the knowledge on the mechanistic relation between environmental (water/sediment) contamination and protective responses (methalothioneins, phase I and II biotransformation, antioxidant enzymes/substrates) and damage effects (lipid peroxidation, genotoxicity, endocrine disruption) in aquatic key organisms living in impacted coastal environments. Particular attention will be devoted to investigate the linkage between genotoxicity (measured as DNA strand-breaks, SCE, micronuclei and erythrocytic nuclear anomalies) and the occurrence of the major oxidative DNA product 8-hydroxy-2’-deoxyguanosine (8-OHdG) as a sensitive marker of DNA damage by oxygen free radicals.
- Develop an adaptive mathematical model, based on biologically sound principles and interaction with contaminants isolated and in mixtures, to predict effects on metals in the life history of aquatic species.
- Assess the genotoxicity potential (measured as Comet assay, micronuclei and erythrocytic nuclear anomalies) of widely used pesticides in fish, performing exposures to individual chemicals as well as combined and sequential exposures to pesticides and other classes of contaminants (e.g. metals and nutrients) likely to be present in aquatic ecosystems and modulating the toxicity of the formers. Moreover, it is also intended to assess the involvement of peroxidative damage on the DNA integrity loss induced by the previous exposure conditions in different key organs/tissues.
- Evaluate the risks of several organic and inorganic nanomaterials with different industrial applications, integrating ecotoxicological evaluation as well as the fate and mobility of substances on water and soil compartments and direct and indirect effects on individuals and populations
- Identify and characterize the metal and radionuclide resistant bacteria endophytes and plasmids, isolated from plant species inhabiting contaminated areas, and evaluate their contribution to improved survival of plants introduced in such areas, for phytostabilisation purposes.
- Identify and validate the natural Portuguese reference soils to be used in ecotoxicological assays developed as part of site-specific risk assessments, and for the establishment of Portuguese soil quality criteria.
The Ecotoxicology RG is organized in 3 Labs that support ongoing research activities:
- Toxicology and Citometry Laboratory
- Environmental Risk Assessment Laboratory (Laboratório de Avaliação de Risco Ambiental)
- Environmental Biomonitoring Laboratory (Laboratório Biomonitorização Ambiental)
The Toxicology and Cytometry Laboratory (TCL) is focused on the understanding of toxicity mechanisms of the main classes of contaminants (e.g. metals, PAHs, pesticides, nanomaterials - NM) and biotoxins, in a wide range of organisms, from bacteria, dinoflagellates, crustacean and fish up to mammalian/human systems. Adopting in vitro, ex vivo and in vivo approaches. The processes addressed encompass oxidative stress, biotransformation, endocrine disruption, neurotoxicity and genotoxicity, keeping in view an integrative interpretation of toxicity pathways.
The Lab includes researchers with multiple levels of expertise, with emphasis on Flow cytometry (FCM). FCM is a powerful tool in toxicology a with broad range of applications. The team is currently focused on: i) Evaluation of population dynamics under contexts of environmental contamination; ii) Assessment of toxicity of NM towards human and animal cells by evaluating a panel of endpoints related with cytotoxic, genotoxic and inflammation responses (e.g. cell viability, NM uptake, apoptosis, oxidative imbalances, mitochondrial function, cell cycle dynamics and quantification of cytokines).
The Toxicology and Citometry Laboratory is lead by Prof. Mário Pacheco.
The activities of the Environmental Risk Assessment Laboratory (RISKA) focus mainly on:
i) assessing the suitability of toxicity parameters associated with pesticides, derived in temperate climates, for Ecological Risk Assessment under tropical conditions;
ii) the utilization of European Ecological Risk Assessment schemes for contaminated sites (abandoned mine areas), in order to improve quantity and quality of data gathered and also a progressive reduction in the uncertainty of the evaluations;
iii) studying the environmental effects of nanomaterials, and other emerging and/or persistent pollutants (POPs), after their release in the aquatic environments as well as their interactions with representatives from different trophic levels;
iv) understanding how alien fish and mollusc species interact with the native species, in order to fully comprehend their impacts and interactions with other environmental stressors and to propose future mitigation measures;
v) the development of mechanistic approaches to model and describe effects of different types of environmental stressors in organisms, including the development of a multi-biomarker approach for aquatic monitoring in a multi-pollution context; vi) the development of a strategy integrating multilevel biological endpoints for use in ecological risk assessment;
vii) merging ecological theory with ecotoxicology, by assessing ecologically relevant endpoints and scenarios, focusing on contaminant impacts on biotic interactions and taking into consideration adaptation to stressors; and viii) assessment of causal links between with biodiversity, ecosystem functions and ecosystem services and how they are modulated by environmental pressures.
The Environmental Risk Assessment Laboratory is lead by Prof. Fernando Gonçalves.