Ecotoxicology of emerging contaminants and nanomaterials

The research group investigates the biological/toxicological responses of terrestrial and aquatic (freshwater and marine) organisms (invertebrates and vertebrates) to natural and anthropogenic impacts of emerging environmental contaminants including nanomaterials. The biological responses are investigated at different levels of biological complexity from the molecule to the cell, from tissue to whole organism. A wide range of biomarkers are applied from the biotransformation/detoxification as phases 0, I, II and III played by ABC transport proteins involved in mechanism of xenobiotic resistance (MXR) and the cytochrome P450 system, to neurotoxicity, genotoxicity, cytotoxicity up to endocrine disruption. An ecosystemic approach that explores ecotoxicological impacts at different levels of biological organization is applied. The approach identifies cellular mechanisms that determine the toxicity of environmental contaminants for biota and contribute to the protection of natural ecosystems subject to human pressure and global changes.

In particular, research is focused on pathways of toxicity of classic contaminants such as trace elements, POPs, polycyclic aromatic hydrocarbons (PAHs), organophoshates (chemical weapons and pesticides) carbamates as well as emerging ones as endocrine disruptors, pharmaceuticals and personal care products (PPCPs) (i.e. musk fragrances) and most recently nanomaterials. The models used range from primary cultures of terrestrial and aquatic invertebrates to teleost cell lines (i.e. RTG-2, PLHC-1) and whole organisms (terrestrial and aquatic invertebrates and vertebrates) by in vitro, in vivo and in situ studies. Undergoing recent research focuses on developing innovative toxicity tests both in vitro and in vivo to assess exposure and effects of nanoparticles (i.e. n-TiO2) in marine and freshwater species with particular regards to interactions (co-exposure) with other contaminants of known toxicity and mechanism of action (Trojan horse effect).

The scientific fields of interest are

• Biomonitoring of marine, brackish and river ecosystems by investigating anthropogenic impacts including global changes. Biomonitoring is based on the application of an ecotoxicological integrated approach based on chemical analysis (residues of contaminants) and biological responses (biomarkers) in bioindicator species. Main case studies include harbours and marine coastal areas, industrial sites, chemical warfare agents dumped on seabed, off-shore LNG terminals at sea (LNG), in-shore gas and oil refinery, marine protected areas, marine coastal areas located close to incinerators and sewage treatment plants.
  Main bioindicator species are: the Mediterranean mussel Mytilus galloprovincialis, the sea urchin Paracentrotus lividus, mullet species Mullus barbatus and Mullus surmuletus, Mediterranean sole Solea vulgaris, European sea bass Dicentrarchus labrax and European eel Anguilla anguilla.
  The major emerging contaminants investigated are POPs, PAHs, PCBs, dioxins and furans, PBDEs, flame retardants, trace metals, synthetic musk fragrances, TNT, mustard gas, surfactants including nonylphenol (p-nonylphenol), phthalates, nanomaterials such as metal nanoparticles (titanium dioxide, zero valent iron), polystyrene, carbon nanotubes.
• Ecotoxicology of nanomaterials and emerging contaminants at the phase 0, I and III of cellular biotransformation in fish immortalized cell lines (PLHC-1, RTG-2). Main investigations are focused on the interaction of MXR and P450 systems with synthetic musk fragrances (musk xylene, musk ketone, tonalide), TNT, n-TiO2 alone and in combination with cadmium and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (Trojan horse effect).
• Standardized ecotoxicological tests (OECD, ASTM, EPA) under the REACH and innovative ones under development using marine invertebrates (Mytilus sp., P. lividus) and teleosts (D. labrax) for assessing acute and chronic toxicity exposure to surfactants, marine sediments and engineered nanomaterials for various applications including drug delivery and remediation of contaminated marine matrices as sediment and sea water (nanoremediation).
• Mechanisms of absorption, distribution, metabolism and excretion (ADME) of persistent and emerging pollutants including nanomaterials using in vitro and in vivo models. Main investigation are focus on the impact of engineered nanoparticles during sea urchin development (P. lividus).
• Safety and welfare of farmed fish in aquaculture. The main case studies are toxicological impact of rearing environments in marine fish (i.e. land and in-shore mariculture), quality of the diet (feed), stress from captivity.
• Evolutionary adaptations at the gene level in response to anthropogenic pressure of physical and chemical nature in both temperate and Antarctic ecosystems. Main case studies are the expression of resistance genes as acetylcholinesterase (AChE) and the over-expression of some ABC transport proteins (ABCB1 encoding for P-glycoprotein, P-gp) in alien species and their potential role in invasiveness.
• Role of xenobiotics in cell and tissue pathology with particular regard to hormone metabolism and immune response. Main case study concerns the interaction of p-nonylphenol with human reproduction, the production of cytokines in the placenta and the P-glycoprotein (MDR).