| Title | Toxicity risk assessment of mercury, DDT and arsenic legacy pollution in sediments: A triad approach under low concentration conditions. |
| Abstract | The determination of sediment toxicity is challenging due to site-specific factors affecting pollutants distribution and bioavailability, especially when contamination levels are close to expected non-effect concentrations. Different lines of evidence and sensitive tools are necessary for a proper toxicity risk assessment. We examined the case study of the Toce River (Northern Italy), where past industrial activities determined Hg, DDT and As enrichment in sediments. A triad approach comprising chemical, ecotoxicological and ecological analyses (benthic invertebrates) was carried out for risk assessment of residual contamination in river sediments. A "blank" site upstream from the industrial site was selected to compare the other sites downstream. Sediment, water and benthic invertebrate samplings were carried out following standard protocols. Results emphasized that despite the emissions of the industrial site ceased about 20years ago, sediments in the downstream section of the river remain contaminated by Hg, DDT and As with concentrations exceeding Threshold Effect Concentrations. A chronic whole-sediment test with Chironomus riparius showed decreased development rate and a lower number of eggs per mass in the contaminated sediments. Benthic community was analyzed with the calculation of integrated (STAR_ICMi) and stressor-specific metrics (SPEARpesticide and mean sensitivity to Hg), but no significant differences were found between upstream and downstream sites. On the other hand, multivariate analysis (partial Redundancy Analysis and variation partitioning) emphasized a slight impact on invertebrate community, accounting for 5% variation in taxa composition. Results show that legacy contaminants in sediments, even at low concentrations, may be bioavailable and possibly toxic for benthic invertebrates. At low concentration levels, sensitive and site-specific tools need to be developed for a proper risk analysis. |
| Source | Science of the total environment 593-594, pp. 809–821 |
| Keywords | Pesticidetrace elementsediment toxicityERABenthic invertebrate communityC. riparius chronic test |
| Journal | Science of the total environment |
| Editor | Elsevier, Lausanne ;, Paesi Bassi |
| Year | 2017 |
| Type | Articolo in rivista |
| DOI | 10.1016/j.scitotenv.2017.03.219 |
| Authors | Marziali, L; Rosignoli, F; Drago, A; Pascariello, S; Valsecchi, L; Rossaro, B; Guzzella, L |
| Text | 370872 2017 10.1016/j.scitotenv.2017.03.219 ISI Web of Science WOS WOS 000401201800083 Scopus 2 s2.0 85016395283 Pesticide trace element sediment toxicity ERA Benthic invertebrate community C. riparius chronic test Toxicity risk assessment of mercury, DDT and arsenic legacy pollution in sediments A triad approach under low concentration conditions. Marziali, L; Rosignoli, F; Drago, A; Pascariello, S; Valsecchi, L; Rossaro, B; Guzzella, L Water Research Institute National Research Council IRSA CNR , Via del Mulino 19, 20861 Brugherio, MB, Italy. Electronic address marziali@irsa.cnr.it. University of Milan, Department of Food, Environmental and Nutritional Sciences DeFENS , Via Celoria 2, 20133 Milan, Italy The determination of sediment toxicity is challenging due to site specific factors affecting pollutants distribution and bioavailability, especially when contamination levels are close to expected non effect concentrations. Different lines of evidence and sensitive tools are necessary for a proper toxicity risk assessment. We examined the case study of the Toce River Northern Italy , where past industrial activities determined Hg, DDT and As enrichment in sediments. A triad approach comprising chemical, ecotoxicological and ecological analyses benthic invertebrates was carried out for risk assessment of residual contamination in river sediments. A blank site upstream from the industrial site was selected to compare the other sites downstream. Sediment, water and benthic invertebrate samplings were carried out following standard protocols. Results emphasized that despite the emissions of the industrial site ceased about 20years ago, sediments in the downstream section of the river remain contaminated by Hg, DDT and As with concentrations exceeding Threshold Effect Concentrations. A chronic whole sediment test with Chironomus riparius showed decreased development rate and a lower number of eggs per mass in the contaminated sediments. Benthic community was analyzed with the calculation of integrated STAR_ICMi and stressor specific metrics SPEARpesticide and mean sensitivity to Hg , but no significant differences were found between upstream and downstream sites. On the other hand, multivariate analysis partial Redundancy Analysis and variation partitioning emphasized a slight impact on invertebrate community, accounting for 5% variation in taxa composition. Results show that legacy contaminants in sediments, even at low concentrations, may be bioavailable and possibly toxic for benthic invertebrates. At low concentration levels, sensitive and site specific tools need to be developed for a proper risk analysis. 593 594 Published version http //www.sciencedirect.com/science/article/pii/S0048969717307507 Toxicity risk assessment of mercury, DDT and arsenic legacy pollution in sedimentsA triad approach under low concentration conditions paper Marziali etal17 RiskAssessmentToce STOTEN.pdf Articolo in rivista Elsevier 0048 9697 Science of the total environment Science of the total environment Sci. total environ. lucia.valsecchi VALSECCHI LUCIA ROSIGNOLI FEDERICA PAOLA liciamaria.guzzella GUZZELLA LICIA MARIA laura.marziali MARZIALI LAURA TA.P04.021.008 Tossicita ed effetti di inquinanti antropici e/o naturali in ecosistemi acquatici |
