title: Bioassay-directed fractionation of marine sediment solvent extracts from the east coast of Ireland.
abstract: Crude solvent extracts were prepared from three sediment sites in Ireland namely Bull Lagoon, Dunmore East and Dublin Port. These were assayed with Tisbe battagliai and the Microtox system. The extracts were chemically characterised using a variety of analytical techniques for a suite of organic contaminants. Metals and organic contaminant concentration data are reported for the three sites. On the basis of determined toxicity and chemical analysis of these crude extracts, a further bioassay-directed fractionation (BDF) employing the Dunmore East crude organic extract was conducted in addition to chemical analysis. For the crude extracts, T. battagliai and Microtox system demonstrated an order of decreasing toxicity for each of the three sites to be Dublin Port>Dunmore East>Bull Lagoon. Microtox system EC10 values after 30min exposure were 1.08%, 11.6% and 26.9% solvent extract for these sites, respectively. Fractionation of the Dunmore East extract revealed that fraction 1 was the most toxic fraction to both the T. battagliai and the Microtox system demonstrating EC50's after 48 h and 30 min of 44.7% and 16.8% solvent extract for the T. battagliai and Microtox assays, respectively. T. battagliai however did show increased sensitivity to fraction 3 when comparing EC10 values and demonstrated an EC10 value of 17.8% solvent extract after 48h. Fraction 1 was shown to contain the highest quantity of the butyltins, in particular TBT in relation to fractions 2 and 3. A useful BDF technique was developed and employed in this study.
authors.affiliation: Marine Institute, Rinville, Oranmore, Co. Galway, Ireland. giltrapm@tcd.ie
authors.forename: Michelle
authors.initials: M
authors.lastname: Giltrap
authors.forename: Ailbhe
authors.initials: A
authors.lastname: Macken
authors.forename: Brendan
authors.initials: B
authors.lastname: McHugh
authors.forename: Robert
authors.initials: R
authors.lastname: Hernan
authors.forename: Kathleen
authors.initials: K
authors.lastname: O' Rourke
authors.forename: Evin
authors.initials: E
authors.lastname: McGovern
authors.forename: Barry
authors.initials: B
authors.lastname: Foley
authors.forename: Maria
authors.initials: M
authors.lastname: Davoren
mesh_terms: D000818:Animals; D001681:Biological Assay / Q000379:methods*; D005591:Chemical Fractionation / Q000379:methods*; D033342:Copepoda / Q000187:drug effects; D019015:Geologic Sediments / Q000032:analysis*; D007494:Ireland; D008670:Metals / Q000032:analysis; D009930:Organic Chemicals / Q000032:analysis* / Q000302:isolation & purification; D012623:Seawater; D012989:Soil Pollutants / Q000032:analysis* / Q000302:isolation & purification; D012997:Solvents / Q000737:chemistry*
chemical_list: D008670:Metals; D009930:Organic Chemicals; D012989:Soil Pollutants; D012997:Solvents