Modelling partitioning and distribution of micropollutants in the lagoon of Venice: a first step towards a comprehensive ecotoxicological model (original) (raw)

PCDD/F contamination of the Venice Lagoon: A history of industrial activities and past management choices

Aquatic Ecosystem Health and Management

The history of the Venice Lagoon contamination is presented here, based on sediment records and on information about industrial activities and past management choices. We used polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) as tracers since the relative abundance of their congeners can help in locating their sources. The most important PCDD/F source to the canals of the first industrial area (built in the 1920s) can be ascribed to processes involving pyrite to obtain sulfuric acid and recovery of copper and other metals. Indeed, homologue profiles and documents show that the PCDD/Fs contamination is mainly related to the use and disposal of both these industrial wastes and materials dredged from the most contaminated canals. In particular, these latter constitute the ground under the second industrial area (built after World War II). Furthermore, hazardous materials were stored until 1992 in an islet exposed to erosion, whereas tracts of industrial canal banks eroded u...

Persistent Organic Pollutant in the Venetian coastal environment

2013

The Venetian coastal area is characterized by a strong anthropogenic impact and its quality is very important because of local economical activities, such as tourism or fishing. In the context of the Water Framework Directive (WFD, 2000/60/EC), the aim of the project Q-ALiVe (Qualita dell’Ambiente Litoraneo Veneto) is to check the environmental quality of the Venetian coastal area and whether rivers contamination could influence it. We studied an area going from the mouth of the Adige river to the Malamocco inlet of the Venice lagoon (including the mouth of the Brenta river and the Chioggia lagoon inlet), to distance from the coast of up to about a kilometer. In this work we presented the data relative to Persistent Organic Pollutants (POPs) as PCBs, PBDEs and PAHs, in samples of seawater. Samples were collected during four different sampling campaigns, in different seasons (June 2011, August 2011, September 2011, November 2011); in each sampling campaign we collected 10 samples of ...

Substantial Decrease in Contaminant Concentrations in the Sediments of the Venice (Italy) Canal Network in the Last Two Decades—Implications for Sediment Management

Water

The Venice canal network requires periodic intervention to remove sediments that progressively accumulate. The most recent dredging operation was carried out in the second half of the 1990s and early 2000s. These sediments had accumulated over a period of more than 30 years and were highly contaminated with Cd, Cu, Hg, Pb, Zn and PAHs. Sediments deposited after the dredging work were investigated in 2005, 2009, 2014 and 2017 by analysing sediment cores collected from three sites in the canal network. Arsenic, heavy metal and PAH concentrations were observed to be much lower than past values, although Cu, Hg and PAH levels were still relatively high. The high Cu concentrations (mean 161 mg kg−1) are partly due to the widespread use of Cu-based antifouling paint. Current Italian regulations forbid the disposal of dredged sediments with these concentrations inside the lagoon, thereby increasing the cost of canal network maintenance.

Accumulation of polychlorinated biphenyls in sediments of the Venice Lagoon and the industrial area of Porto Marghera

Chemosphere, 2004

Sediment cores, collected at seven sites in the Venice Lagoon and within the canals of the industrial area were analyzed for polychlorinated biphenyls (PCBs) in order to assess the chronology of pollution and its present trends. The surficial concentration of PCBs is very high (more than 2049 μg kg−1) only in the Brentella Canal, probably due to a very recent contaminating episode. Very high values downcore (up to 41 639 μg kg−1) can be found in different parts of the industrial area, especially in the canals Lusore-Brentelle and Salso. Lagoon samples are much less contaminated (2.7–123 μg kg−1), being influenced only occasionally by polluted sediments resuspended from the canals. Sediment chronology shows that the delivery of contaminants peaked in the 1970s–early 1980s, decreasing since at most sites. Congener profiles distinguish PCBs in two main categories: heavy congeners characterize a baseline pollution, probably due to a large variety of sources within the lagoon system, whereas a mixture of light PCBs was discharged into the canals Brentella and Salso.

Accumulation of Polychlorinated Dibenzo- p-Dioxins and Dibenzofurans in Sediments of the Venice Lagoon and the Industrial Area of Porto Marghera

Marine Pollution Bulletin, 2001

Two sediment cores collected from the central Venice Lagoon and five from the canals of the nearby industrial area were studied in order to assess the temporal evolution of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) delivery and present trends. The most polluted site is C12, in the Brentella Canal, with a total equivalent (TEQ) concentration of 2858 and 64,130 ng kg-1 at the surface and at 18-20 cm depth, respectively. High values can be also found in the Nord Industrial Canal and in the Salso Canal: 3000 and 2500 ng kg-1, respectively. Lagoon samples are much less contaminated, with TEQ downcore maxima of 22 and 53 ng kg-1, being influenced by pollutants stored in sediments of the canals only occasionally. Sediment chronology, based on 210Pb and 137Cs activity-depth profiles, shows that the highest fluxes occurred in the 1970s and early 1980s, and that pollution is now decreasing. Homologue profiles can distinguish PCDD/Fs from different sources: combustion for octachlorinated dibenzo-p-dioxin (OCDD) and stripping of VCM for octachlorinated dibenzofuran (OCDF) alone, whereas several activities carried out in the past within the industrial area can be responsible of the overall contamination by furans.