Effects of Long Term Hg Contamination on Soil Mercury Speciation and Soil Biological Activities.

The suspended matter discharged by the Isonzo river has carried over, for centuries, heavily contaminated mine spoils from the Idrija mercury mining site (Slovenija). A frequently flooded area at the confluence of the Isonzo and Torre rivers was chosen for a preliminary study on the effects of long term mercury pollution on soil biological activities, Hg speciation and plant bioavailability. Soil mercury contamination reached up to about 80 \ub5g g-1 near the banks of Isonzo river and decreased down to about 0.2 \ub5g g-1 near the Torre river, with the predominance of mercuric sulfide and elemental mercury. Soil microbial biomass was not adversely affected by Hg contamination as most soil biological activities, with the exception of arylsulphatase and acid phosphatase, which showed significant negative trends against total mercury and its fractions. Two plant genres (Arum spp. and Rubus spp.) were collected in four different places: Rubus spp. showed the largest uptake capacity of mercury (about 1 \ub5g g-1). Long term mercury contamination does not seem to constitute a stressing factor for soil biological activities but remains nevertheless a concern for its transfer through the food chain

A New Multi-Index Method for the Eutrophication Assessment in Transitional Waters: Large-Scale Implementation in Italian Lagoons

Eutrophication represents one of the most impacting threats for the ecological status and related ecosystem services of transitional waters; hence, its assessment plays a key role in the management of these ecosystems. A new multi-index method for eutrophication assessment, based on the ecological index MaQI (Macrophyte Quality Index), the trophic index TWQI (Transitional Water Quality Index), and physicochemical quality elements (sensu Dir. 2000/60/EC), was developed including both driver and impact indicators. The study presents a large-scale implementation of the method, which included more than 100 Italian lagoon sites, covering a wide variability of lagoon typologies and conditions. Overall, 35% of sites resulted in eutrophic status, 45% in mesotrophic, and 25% in oligotrophic status

Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study

A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4

Natural background values for heavy metals in the sediments of a contaminated Northern Adriatic lagoon environment: a geochemical perspective

Major and trace elements were determined in 14 sediment cores collected from the Marano and Grado Lagoon (northern Adriatic sea). The lagoon is contaminated by several harmful priority substances, heavy metals included, and it has also been declared a “polluted site of national interest” (SIN) mainly due to high Hg concentrations in sediments. Based on a normalization procedure involving predicted linear relationships for “metal vs Al” obtained from the core subsamples, background values for each metal were evaluated on a regional scale and according to the grain-size variability. Compared to Environmental Quality Standards reported in the Italian laws and regulations, the estimated background ranges show that bottom sediments are naturally “enriched” in some metals, such as Cr, Ni and Cd especially in sediments with a high percentage of the fine component. A correct evaluation on sediment quality status should be made on the basis of regional background values for each metal, taking into account local geochemical characteristics, i.e. mineralogical composition and grain-size variability of sediments

Heavy metals in sediments and halophytes of saltmarshes in the Marano and Grado Lagoon (Northern Adriatic Sea)

The content of several heavy metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn) was determined in sediments and in plants (the halophytes Sarcocornia fruticosa and Limonium vulgare) from two selected saltmarshes located in the Marano and Grado Lagoon (Northern Adriatic Sea). This environment has been affected by severe Hg contamination from both industrial and long-term mining activities. In both saltmarshes, Hg content in sediments exceeded the estimated background value (0.13 μg g−1), showing the highest concentrations (13.7 μg g−1) in the eastern sector (Grado Lagoon), the most affected by cinnabar ore extraction. On the other hand, the saltmarsh, located in the Marano Lagoon, showed a higher degree of contamination for As, Cd and Pb, which can be related to industrial sources. The rhizo-sediments of both halophytes reflected the characteristics of the non-vegetated sediment, with higher organic carbon content and similar metal concentrations. Enrichment Factors (EF=[metal]root/[metal]rhizo-sediment) for each sediment layer were calculated for both halophytes, showing metal enrichments in the roots and the presence of preferential layers of metal accumulation. Hg showed accumulation (EF>1) in the roots below the 20 cm depth, with higher contents in S. Fruticosa. As and Cd were accumulated by both halophytes, more efficiently by S. Fruticosa, and the same species showed also accumulation of Pb and Zn. Translocation of metals from the roots to the aboveground biomass was investigated by measuring metal contents in shoots and leaves of the two species. With the exception of Cd and Hg, all metals were present in the aboveground biomass, most evidently for Cr in S. Fruticosa and Zn in L. Vulgare, although the presence of the latter in leaves could be due to plant physiology rather than translocation of the contaminant

Historical flux of mercury associated with mining and industrial sources in the Marano and Grado Lagoon (northern Adriatic Sea)

The \u201cMIRACLE\u201d Project was established in order to assess the feasibility of clam farming and high levels of sediment mercury (Hg) contamination coexisting in the Marano and Grado Lagoon, Italy. This lagoon has been subjected to Hg input from both industrial waste (chlor-alkali plant) and long-term mining activity (Idrija mine, NW Slovenia). One of the subtasks of the \u201cMIRACLE\u201d Project was to determine the historical evolution of Hg accumulation in the lagoon\u2019s bottom sediments. Thirteen 1-m deep sediment cores were collected from the subtidal and intertidal zones, plus one in a saltmarsh, all of which were then analyzed for total Hg content and several physicochemical parameters. Sedimentation rate assessments were performed by measuring short-lived radionuclides (excess 210Pb and 137Cs). For most of the analyzed cores, natural background levels of Hg were observed at depths of 50 e 100 cm. In the eastern area, Hg contamination was found to be at its maximum level at the core top (up to 12 mg g-1) as a consequence of the long-term mining activity. The vertical distribution of Hg was related to the influence of the single-point contamination sources, whereas the grain-size variability or organic matter content seemed not to affect it. In the western area, Hg content at the surface was found not to exceed 7 mg g1 and contamination was recorded only in the first 20e30 cm. Geochronological measurements showed that the depositional flux of Hg was influenced by anthropogenic inputs after 1800, when mining activity was more intense. After 1950, Hg in the surface sediment, most remarkable in the central-western sector, seemed to also be affected by the discharge of the Aussa River, which delivers Hg from the chlor-alkali plant. In 1996, Hg mining at Idrija ceased, however the core profiles did not show any subsequent decreasing trend in terms of Hg flux, which implies the system retaining some \u201cmemory\u201d of contamination. Thus, in the short term, a decrease in Hg inputs into the nearby Gulf of Trieste and the lagoon seems unlikely. A preliminary rounded-down gross estimate of total Hg \u201ctrapped\u201d in the lagoon\u2019s sediments amounted to 251 t. Such a quantity, along with the complexity of the lagoon ecosystem, suggests that an in toto reclamation of the sediments at the lagoon scale is unfeasible, both economically and environmentally

Organic Carbon and humic substances in sediments of Grado and Marano Lagoon

Mercury contamination in sediments is a major concern, especially, in bivalves farming area, due to the potential risk of bioaccumulation. A substantial fraction of the so-called refractory organic matter in sediments is constituted by humic substances (HS). HS are ecognized to play an important role in complexing heavy metals, mercury included, thus favoring their mobilization or accumulation in sediments. In the framework of the MIRACLE project (Mercury Interdisciplinary Research for Appropriate Clam farming in Lagoon Environment) sediment cores have been sampled in 15 stations located in Grado and Marano lagoon and in 4 stations in Aussa River, one of the main freshwater inputs in this environment. The aim of our study was the evaluation of the organic carbon content in sediments, the estimation of the contribution of humic substances to total organic carbon and the elemental characterization of HS. Riverine sediments showed high organic carbon values (mean 2.46\ub11.47 %), increasing upstream from the river mouth and C/N atomic ratios higher (8.7\ub12.14) than lagoon sediments. Organic carbon content was similar in surficial and sub-surficial lagoon sediments (mean values 1.28\ub10.53 and 1.28\ub10.62 respectively), but higher C/N ratio have been observed in the deeper levels of the cores (7.1\ub11.5 with respect to 8.0\ub11.6 in the surficial layer). Humic substances extracted from sediments showed a high carbon content (mean 50.5\ub11.5 %). Humic acids concentrations in sediments fall in the range 1.8-31 mg g-1. The contribution of humic carbon to total organic carbon was relevant (up to 39.5 %), pointing out the important role of HS in the accumulation and transformation of organic material in the lagoon environment. Preliminary data showed no differences of the humic contribution to total organic carbon among upper and deeper levels of the cores