Evaluation of Corophium orientale as bioindicator for Venice Lagoon: Sensitivity assessment and toxicity-score proposal

Abstract

The 96-h water-only exposure and 10-d sediment toxicity tests with the amphipod Corophium orientale were performed in order to enhance the knowledge about its overall sensitivity and its applicability to Venice Lagoon sediments. The values obtained with cadmium as reference toxicant demonstrated a certain variability of the LC(50); the higher value was found in spring and the lower in late summer. Tests with other pure chemicals (Ni, Total Ammonia, Sodium Dodecyl-Sulphate) showed good discriminatory power; the toxicity gradient observed was: Cd (LC(50) of 3.3 mg/L)>SDS (LC(50) of 8.7 mg/L)>total ammonia (LC(50) of 126mg/L)>Ni (LC(50) of 352 mg/L). Sediment toxicity test results were used to obtain information on non-treatment factors (grain-size, TOC content) that could act as confounding factors, and to develop a site-specific toxicity-score based on minimum significant difference approach. Confounding factors seem not to affect test results. The procedure to develop the toxicity score took into account the relatively lower sensitivity of C. orientale with respect to other amphipods commonly used in toxicity tests (Ampelisca abdita and Rhepoxynius abronius).

Comparative study based on sediment characteristics and macrobenthic communities in two Italian lagoons

“…With regard to TOC content, the results of this study were comparable or even lower than those typically found in organic enriched or eutrophic Mediterranean lagoons with economic rating due to fisheries and aquaculture exploitations, such as Venice lagoon (0.5 to >30% TOC, Picone et al 2008), Fattibello-Spavola (1.2-3.9% TOC, Frascari et al 2002), Orbetello lagoon (2-7% TOC, Lardicci et al 2001;Lenzi et al 2005), Santa Giusta lagoon (0.48-3,9% TOC, Magni et al 2008b), Cabras lagoon (3.4-6.28% TOC, Magni et al 2005;Como et al 2007). Higher value of TOC were also found in Pabellon lagoon on the north west coast of Mexico, surrounded by intensive agricultural area (0.5-11% TOC, Paez-Osuna et al 1998) or Rio Formosa in southern Portugal which has increased nutrient loading due to land runoff and sewage discharges (0.15-8.3% TOC, Mudge et al 1998).…”

Ecotoxicological effects of sediments from Mar Piccolo, South Italy: toxicity testing with organisms from different trophic levels

“…Similar results were also observed in the whole-sediment test with the amphipod C. insidiosum. It is well known that when using a battery of bioassays for sediment assessment, the use of sediment reworker species is recommended for the high ecological relevance of whole sediment testing (Picone et al 2008). Knowledge about the use of amphipods for sediment toxicity assessment is very wide.…”

Assessment of sediment toxicity in the Lagoon of Venice (Italy) using a multi-species set of bioassays

“…Ten sampling sites within the Lagoon of Venice (Fig. 1) were selected along a gradient of chemical contamination and toxicity, on the basis of previous studies and surveys (MAG.ACQUE-Thetis, 2006;Picone et al, 2008). Three sampling sites (14B -San Pietro in Volta, 19B -Caroman and 24B -Sant'Erasmo) are located near the sea-inlets and characterized by sandy sediments and low levels of contamination.…”

“…International standard guidelines are available for the selected bioassays (USEPA, 2002;ASTM, 2004;ISO, 2005) and specific protocols were previously developed and validated for the application of the water-phase test in Venice Lagoon (Volpi Ghirardini and Arizzi Novelli, 2001, 2006Losso et al, 2004;Volpi Ghirardini et al, 2005a). The applicability in Venice Lagoon of the amphipod standard protocol for sediment testing was already verified by Picone (2006) and Picone et al (2008). Sediment were investigated for the presence of organic carbon (OC), metals, polynuclear aromatic hydrocarbons (PAH), organo-chlorine pesticides (OCP), hexachlorobenzene (HCB), poly- chlorinated biphenyls (PCB) and aliphatic hydrocarbons.…”