Forest fires are considered a major environmental problem in Mediterranean countries of southern-Europe, occurring with a high frequency and affecting large areas. Amongst the distinct impacts of wildfires, their role on the production, mobilization and dispersion of contaminants has been increasingly receiving research attention, particularly in what concerns polycyclic aromatic hydrocarbons (PAHs) and metals. Both PAHs and metals are contaminants of major concern, due to their high persistence, toxicity and tendency to bioaccumulate. Since wildfires can also enhance greatly runoff generation and the associated transport of sediments and ashes, a substantial part of the PAHs and metals attached to ashes can end up in downstream aquatic habitats. Hence, their input into aquatic systems, could lead to toxic effects on aquatic species. Moreover, both PAHs and metals constitute a concerning risk to human health, either by direct consumption of water or contaminated fish, or using water for recreational activities as fishing and swimming. Notwithstanding their importance as a diffuse source of pollution, the toxic effects of wildfires on aquatic systems have been largely ignored by the scientific community. In this sense, members of the proponent team of AQUAFIRE took the first steps towards understanding the toxic impacts of wildfires on aquatic systems through the FIRETOX project (2013-2015).

Assumed as a follow-up of the former proposal, this project will contribute to the advancement and consolidation of knowledge using an integrated approach combining different evidences (chemical, ecological and ecotoxicological) and using high-tier specific tools. It therefore aims at: • assessing the contamination of water bodies by wildfires, with focus on surface water, sediments and aquatic biota in terms of concerning metals and PAHs; • assessing immediate and short-to-medium term impacts of wildfires on key aquatic communities and ecosystem functions; • assessing the toxic effects of wildfires on aquatic ecosystems using distinct and complementary high-tier perceptive ecotoxicological tools; • using a Weight-of-Evidence approach to assess the risks of wildfires to aquatic ecosystems and human health; • developing an aassessment protocol based on key-indicators. Aligned with the Portuguese Strategy for Smart Specialisation and the Research and the Innovation Strategies for Smart Specialisations (RIS 3), the outcome of this project will represent an advancement in the state-of-the-art providing novel findings and a sound scientific basis for assessing and predicting the risks of water contamination to the aquatic biota and human health. Furthermore, the production of an assessment protocol is envisaged as an important contribution to such an integrated assessment of risks of wildfires for aquatic biota and human health, hence considered a valuable and expected tool to apply by authorities with responsibilities on water issues in future wildfires scenarios.