Since the development of nanotechnology industry, engineered nanomaterials and nanoparticles (ENM/Ps) have become common in our daily lives and their massive use in commercial products calls for potential risks to living beings. Similarly, microplastics are present in a plethora of commercial formulations and they also originated from breakdown of larger plastic debris reaching sized even below 1 µm named nanoplastics. ENMs as well as microplastics and nanoplastics are extremely diverse in terms of chemical composition, size, shape, and surface charges, which affect their reactivity also towards living organisms; their behavior in the natural environment and biological compartments are mainly dictated by specific combinations of those properties and by physical and chemical parameters of the receiving environmental matrices (water, soil, air). Being unmonitored and unregulated, their amounts in the environment can approach acute toxicity thresholds with adverse effects on natural biota. Harmful effects on aquatic organisms have mostly been reported in bench-scale studies and single model species but these investigations lack the complexity of natural settings and the intricate interplay between the different environmental compartments (abiotic and biotic) and physiological sensitiveness/acclimation of natural communities.

This session aims to discuss novel and already established methods for investigating biochemical and physiological effects of ENMs and micro and nanoplastics from molecules to ecosystem level using a system biology approach, model and ecologically key species and environmentally relevant concentrations, including new analytical methodological approaches for their detection and quantitation.

The widespread and persistent input of man-made chemical pollutants into the environment is so large that their impact on wildlife can outpace other global stressors. Besides legacy pollutants, substances including but not limited to—rare earth elements, perfluoroalkyl and polyfluroalkyl substances, pharmaceuticals and personal care products, illicit drugs, flame retardants are appearing as contaminants of emerging concern. In this scenario, it is mandatory to increase our knowledge on the processes and interactions with biological systems that drive toxic effects of environmental contaminants. Furthermore, even if in natural conditions organisms are exposed to complex mixture of contaminants, the current knowledge on the impacts of combination of pollutants is still very scarce.

The session aims to gather results of studies concerning the effects of pollutants at different levels of the biological systems: from genetic and molecular, to eco-physiological and eco-toxicological, up to population and species interactions. A special interest will be given to studies focusing on the impacts of complex mixture of chemicals with different mechanisms of action, as well as on studies able to link first interactions with molecular and biochemical targets with impacts occurring at higher hierarchical levels. The investigation of novel end-points of toxicity is also very welcome.

Anthropogenic activities always had an influence on both terrestrial and aquatic environments. From the Industrial Revolution, this influence has progressively increased along with the growing human populations. Increased anthropogenic emission of greenhouse gasses, like CO2, are indicated as the main cause for warming and ocean acidification. Furthermore, many areas around the world are contaminated by the steady release of anthropogenic substances that may affect both terrestrial and aquatic organisms through various biological pathways. Several studies have provided extensive insight on the physiological and biochemical effects that the alteration of environmental variables related to climate change can have on single organisms. However, most studies in this field have focused their attention on short-term and within generation effects of a single stressor on a precise stage of the life cycle of a specific organism. Although these studies can give the measure of the plasticity of a certain population, they might lead us to over, or under, underestimate the long-term effects that global climate change diminishing our capacity to predict and counteract the risks for natural populations and ecosystems.

Here, in this session, we provide the perfect stage to present data on the current knowledge and understanding of global environmental change, alone or combined with other anthropogenic stressors, through an evolutionary perspective in ecotoxicology.

Aquaculture is the farming of aquatic organisms in both coastal and inland areas involving interventions in the rearing process to enhance production. It is probably the fastest growing food- producing sector and the most efficient form of animal protein production and now accounts for 50 percent of the world's fish that is used for food, a value that is destined to increase. The sustainability of aquaculture has been debated for decades. Potential issues include habitat destruction, the use of marine ingredients in feeds, freshwater usage, using wild juveniles for farm stocking, influencing wild gene pools through farm escapees, and the excessive loss of stock through disease and associated overuse of antibiotics. Making aquaculture sustainable requires an effort on various aspects from the choice of species to the methods with which they are farmed. If we consider the animal aspect, the sustainability of aquaculture passes through the reproduction in captivity of the actually reared species and of new species less demanding in terms of protein food requirements, faster growing and more adaptable to the farming conditions in order to reduce the impact on wild stocks and increase performance. It goes through identifying alternative protein sources to replace marine sources in fish feeds. It goes through the selection of water purification systems that reduce potentially polluting wastewater, the use of water and the occurrence of possible diseases in farms and the spread of pathogens even to wild populations. It goes through the capabilities of farmed species adaptation to climate change currently in progress that inevitably also impact on this type of production.

This session therefore focuses on all these and many other aspects, taking stock of the situation and is open to all contributions that may bring new developments in this area.