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In this study, site-specific natural background levels (NBLs) were determined for 18 elements (Al, As, Be, Cd, Co, Cu, Cr, Fe, Hg, K, Mn, Mo, Ni, Pb, Tl, U, V, and Zn) in two sediment cores collected offshore the Bagnoli-Coroglio brownfield site (Gulf of Pozzuoli, southern Italy) to accurately assess the degree of contamination and the historical trends in Heavy Metals (HMs) enrichment. This objective was pursued taking in account the high temporal and spatial variability of the geochemical properties of the area due to the local geothermal activity. Moreover, the temporal variation of Polycyclic Aromatic Hydrocarbons (PAHs) was investigated.226Ra was used as an extraordinary marker to confirm 210Pb dating. It especially allowed defining the geochronological framework of the sediment core closer the brownfield up to around 1500, providing compelling support to correlate the investigated elements’ occurrences with natural geogenic dynamic. Sediment samples were accurately dated and analyzed for chemical and particle size composition. The contamination factor (Cf) and the pollution load index (PLI) showed very high enrichment of Cd, Cu, Hg, Pb, and Zn. The contamination profiles of HMs and PAHs follow the same pattern in both sediment cores, increasing from deep to upper layers. The highest contamination levels for HMs and PAHs were observed between 10 and 30 cm, corresponding to the periods of most intense industrial activity. Decreasing trends of pollutants were observed in the surface layers (0–10 cm), probably affected by a natural attenuation process due to the cessation of industrial activities.

Coastal lagoons are important but sensitive environments, being transitional zones between land and sea. The Khnifiss lagoon is the most important desert wetland in Morocco, but little data have been produced concerning heavy metal geochemistry and enrichments in the sediments. Therefore, 26 surface sediments (15 intertidal and 11 subtidal) and 2 sediment cores were collected in 2016 and analyzed for a selection of heavy metals. The data were processed to assess the degree of contamination and the corresponding potential ecological risk, using several accumulation/enrichment indices, and the singular and multi-metal risk indices. Mean concentrations in the bottom layers of the two cores, dating from a pre-industrial age according to geochronological analysis, were used as the local geochemical background. The resulting values were on the whole lower than those reported for other areas of the northeastern coast of Morocco. Multivariate statistics were also applied to better understand relationships among variables (metals and other geochemical parameters) and to reveal similarities among sample groups. The results showed that, although the lagoon is not yet affected by significant anthropogenic influences, small enrichments can be recognized, especially for Ni and Cd. The cause may be related to the proximity to the main national highway, the vehicles and machinery used in the saltworks located in the area, and the small harbors used principally for fishing. In addition, industrial emissions from the Atlantic coast of Morocco and adjacent countries can be reasonably attributed as additional contributors to the enrichments. In terms of potential ecological risk, Cd shows the greatest impact compared to the other metals investigated.

The occurrence of three common antifouling biocides (Irgarol, Diuron and dichlofluanid) was investigated, both in winter and summer, in two Italian coastal areas bordering the Tyrrhenian Sea: the Gulf of Napoli (Southern Italy) and the Gulf of La Spezia (Northern Italy). Dichlofluanid was always below the limit of detection, while Irgarol and Diuron were detected in the Gulf of Napoli, at concentrations ranging from 0.8 ng/L to 134.5 ng/L, and from 1.6 ng/L to 34.8 ng/L, respectively. In the Gulf of La Spezia, the amounts were in the range

A variance-based global sensitivity analysis (GSA) was applied to the dose assessment model used in the risk-based corrective action methodology of environmental risk analysis to identify key sources of variability and uncertainty and quantify the relative contribution of these sources to the variance of estimated dose. GSA was performed applying extended Fourier amplitude sensitivity test technique. The soil-to-air contaminant transport pathway within an inhalation exposure scenario was addressed. Three persistent semi-volatile carcinogenic chemicals, including polychlorinated biphenyls, benzo(a)pyrene, and 2,3,7,8-tetrachlorodibenzo-p-dioxin, were chosen as contaminants of concern.

High frequency dissolved oxygen measurements in Mediterranean coastal lagoons show different dynamics on different time scales. In this paper the seasonal and daily dynamics are analysed and discussed and a continuous simulation model is developed to represent them for the salt lake of Fogliano (Italy). Field and laboratory experiments evidenced that primary production slows down in highly oxygenated and irradiated summer days, acting in feedback regime with the oxygen already present in the media, that wind stress contributes in exceeding the oxygen saturation concentration and that there is a firm correlation between oxygen consumption at the sediment layer and overhanging water temperature. Water temperature, solar radiation and wind regime are the forcing functions of the model; the main state variables are dissolved oxygen and detritus in the pelagic and benthic layers, together with carbon dioxide and vegetal biomass. The slow seasonal and fast diel dynamics are both revealed by the model evidencing detailed aspects of oxygen dynamics in a coherent agreement with field observed data trends.

In this work, we evaluated the risk posed to aquatic organisms in the coastal waters of Albania and Apulia (Italy) by two priority pollutants (PPs), Irgarol 1051 and Diuron, used as biocides in antifouling paints on boat hulls. With this aim, we carried out an extensive 3-year monitoring in ports and marinas along the coasts of both countries, which showed a widespread occurrence of both PPs, with Irgarol 1051 concentrations usually being lower than the Diuron ones. The measured concentrations were compared with regulatory Environmental Quality Standards (EQS) (Directive 2008/105/EC) and used to perform a probabilistic Ecological Risk Assessment (ERA), for a thorough evaluation of the potential adverse effects upon marine ecosystem. Irgarol 1051 amounts above the Annual Average Concentration (AA-EQS, 2.5 ng/L) were often detected in Apulia and, less frequently, in Albania. Moreover, in Apulia, sometimes the Maximum Allowable Concentrations (MAC-EQS, 16 ng/L) was exceeded. In Apulia, where levels exceeded MAC/AA-EQS, ERA found not negligible probabilities of exceeding the toxicity level (6–18 %). A less critical situation was observed for Diuron whose levels were always below the MAC-EQS (1800 ng/L) in both countries and, in Albania, also below the AA-EQS (200 ng/L). On the other hand, in Apulia, this limit was exceeded in some locations. Correspondingly, ERA determined a not negligible risk in these sites (probability of exceedance 4–7 %).

Dissolved oxygen evolution over time holds information about the recent and past history of the physics, the chemistry and the biology of aquatic systems. On the daily time scale various phenomena seem to repeat with a sort of regularity, leaving a trace in the further trend of oxygen dynamics. These are the wind calm of nocturnal and early morning hours, the advent of the afternoon breezes, the micro- and macro-algae diurnal production, the chemical and biochemical processes. On the larger seasonal scale, dissolved oxygen shows an almost periodical trend. In this case, a greater dependency on the climatic events leads to the colder and windy season, while the warm and hot period is closely related to the vegetable production, which frees remarkable amounts of oxygen in the water through photosynthesis. Result of experimental measurements of dissolved oxygen, acquired with an automatic equipement on a very short time scale (30 s), are shown and discussed. The experiments were run to detect oscillating phenomena characterized by a period which is shorter than the daily occurrence, as well as stochastic phenomena, led by almost periodical drifts, which contribute substantially to the oxygen dynamics on the longer time scale. To determine these pseudo-periodicities, or time variation for the oscillation period, the analysis of the temporal distances between local maxima of oxygen concentrations has been performed. This kind of analysis is based on the hypothesis that we are dealing with a dissipative dynamical system whose evolution is similar to the behavior of some non linear oscillating systems with a control, where the control can be represented by a simple function of the temporal interval between two consecutive peaks. The result of the analysis suggests the existence of dynamics on a 6–8 h time scale.

The CARISMA project (characterization and ecological risk analysis of antifouling biocides in the Southern Adriatic Sea) aims to appraise the quality of the Southern Adriatic Sea between Italy (Apulia region) and Albania and, in particular, the impact due to the use of biocidal antifouling coatings. Under this project, a preliminary survey at the main hot spots of contamination (e.g. ports and marinas) was conducted at the end of the nautical season in 2012. Chemical seawater analyses were complemented with ecotoxicological assays and the results were analyzed by principal component analysis (PCA). As expected, PCA splits the Albanian and Italian ports, according to the different degrees of contamination indicated for the two countries by the experimental data, highlighting the most critical situation in one port of Apulia. In addition, in order to assess the potential adverse ecological effects posed by antifouling agents (i.e. tributyltin (TBT)-irgarol-diuron) on non-target marine organisms, hazard quotients (HQ) were calculated. The results showed a low risk posed by irgarol and diuron whereas the probability of adverse effects was high in the case of TBT. This journal is � the Partner Organisations 2014.