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The effective management of marine ecosystems in the face of growing anthropogenic pressures requires the integration of data from different ecological components. Holistic approaches to evaluate the ecological status of marine ecosystems are still scarce, likely due to the challenge of integrating the complex information from a variety of indicators. In this study, we provided an application of a quantitative Weight-Of-Evidence (WOE) model based on the Sediqualsoft® software, combining environmental and biological data to assess ecological risk in soft-bottom habitats within Natura sites 2000 in the Northern Adriatic Sea (Mediterranean Sea). Here, the WOE approach combined three lines of evidence (LOE): chemical characterization (LOE1), ecotoxicological properties (LOE4), and benthic community status (LOE5). A separate hazard quotient was derived for each LOE prior to a weighted integration into a synthetic WOE assessment. The chemical analysis of the sediments revealed concentrations of pollutants far lower the reference limits, except for As and Hg and for polycyclic aromatic hydrocarbons which determined a ‘Slight’ to ‘Severe’ chemical hazard in coastal sites. Ecotoxicological hazard was rated as ‘Absent’ at all sampling stations, and the analysis of benthic communities indicated ‘undisturbed’ conditions for most sites. The WOE approach classified the overall ecological risk to be ‘Absent’ for offshore sites and ‘Slight’ in nearshore sites. Although results suggested a general low ecological risk, the potential for future risks is recognized, especially in coastal areas, due to well-known sediment pollution in the region. The application of the WOE approach may represent a valuable tool for managing marine protected sites, and to characterize the overall ecological status of these areas and improve conservation strategies in highly anthropized environmental contexts.

Cigarette butts (CBs), one of the most common litter items found on beaches, represent a still unexplored environmental hazard. This study aimed at a multidisciplinary characterization of their toxicological risks on marine organisms integrating chemical analyses of released compounds with a wide panel of biological responses, such as ecotoxicological bioassays on species of different trophic positions, molecular responses in an ex vivo model (Precision-Cut Tissue Slices, PCTS of mussels digestive glands), bioavailability and cellular biomarkers in mussels exposed to CBs in laboratory experiments. Trace metals, aliphatic and polycyclic aromatic hydrocarbons, nicotine and cotinine were released in artificial seawater after 24 h which determined a significant inhibition of bacterial bioluminescence, oyster embryo development and growth in different algal species. Modulation of peroxisomal proliferation and antioxidant gene expression was observed in mussels PCTS, while the in vivo exposure determined accumulation of chemicals and significant alterations of immune system, antioxidant and neurotoxic responses, peroxisomal proliferation and genotoxic damage. Using a quantitative Weight of Evidence model, the risks of CBs to the marine environment were summarized, highlighting the importance of integrating chemical analyses, batteries of ecotoxicological bioassays, molecular and cellular biomarkers to assess the impact of these hazardous materials on marine environment.

Contaminants of emerging concern and ocean changes are key environmental stressors for marine species with possibly synergistic, but still unexplored, deleterious effects. In the present study the influence of a simulated ocean acidification scenario (pH = 7.6) was investigated on metabolism and sub-lethal effects of carbamazepine, CBZ (1 µg/L), chosen as one of the most widely diffused pharmaceuticals in marine organisms. A multidisciplinary approach was applied on mussels, M. galloprovincialis, integrating measurement of drug bioaccumulation with changes in the whole transcriptome, responsiveness of various biochemical and cellular biomarkers including immunological parameters, lipid and oxidative metabolism, onset of genotoxic effects. Chemical analyses revealed a limited influence of hypercapnia on accumulation and excretion of CBZ, while a complex network of biological responses was observed in gene expression profile and functional changes at cellular level. The modulation of gamma-aminobutyric acid (GABA) pathway suggested similarities with the Mechanism of Action known for vertebrates: immune responses, cellular homeostasis and oxidative system represented the processes targeted by combined stressors. The overall elaboration of results through a quantitative Weight of Evidence model, revealed clearly increased cellular hazard due to interactions of CBZ with acidification compared to single stressors.