Effects of the unresolved complex mixture (UCM) of petrogenic oils: Impacts in the seawater column

Transcription

1 Effects of the unresolved complex mixture (UCM) of petrogenic oils: Impacts in the seawater column T. Nordtug 1, O.G. Brakstad 1, A.G. Melbye 1, J. N. Hokstad 1, D. Altin 2, K.-E. Tollefsen 3, M. Grung 3, D. and S. Rowland 4 1 SINTEF, Trondheim, 2 Biotrix, Trondheim, 3 NIVA, Oslo, and 4 University of Plymouth 1

2 The unresolved complex mixture (UCM of petrogenic oils: Impacts in the seawater column Objectives Determination of toxicity of the UCM-rich fractions of crude oils Toxicity contribution of essential UCM fractions from evaporated and photo-transformed oils Duration: March December 2005 Participants: SINTEF, NIVA, University of Plymouth, Biotrix/NTNU 2

3 What do we know about the hump (UCM fraction of oil) in nature? The UCM fraction increases during: Photo-oxidation Biodegradation Weathering in general The UCM interacts with biota. Source of non-specific narcosis Affecting feeding or clearance rate of mussel M. edulis (e.g. Widdows, Donkin et al. 1995,Proc.Roy. Soc Edin., 103B, ). Persistence in the tissue of marine animals 3

4 Effect of a monoaromatic UCM on mussel feeding rate over 24 hr mussel feeding rate (L hr -1 ) total body burden monoaromatic UCM (ug g -1 wet weight) % reduction Rowland et al., 2001 ES &T, 13,

5 Links to other ongoing projects "Chemical characterization of polar components in produced water" (NFR Project no ) "Integrating monitoring methods for impacts of offshore discharges to the North Sea (IMONIT" (NFR Project no ) "Long-term -chronic - effects of produced water effluents affecting reproduction in marine crustacean plankton" NRF Project no

6 Procedures for creating test medium Generation of WSF Extraction in dichloromethane (DCM) Evaporation of DCM (to approx. 1 ml) Fractioning by HPLC (polarity gradient: hexane DCM - methanol) Solvent transfer to Dimethyl Sulfoxide (DMSO) Dilution in water 6

7 Generation of WSF Oil:water ratio - 1:100 Volume approx. 60 L Method adopted from CROSERF: Slow stirring for 72 hours and colection of water phase with water soluble fraction (WSF) Foto T. Nordtug 7

8 Fractioning Fractioning was done by a modified HPLC system with repeated fractioning into bottles (one for each fraction) Foto A. G. Melby 8

9 Toxicity of solvents Microtox Effect (%) Acetone (EC 50 = 3.46 %) Ethano (EC 50 = 7.51 %) DMSO (EC 50 = %) Conc. (% dilution) 9

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11 Toxic units (TU) Fish bioassay preliminary results Cytotoxicity F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 RET Sample Metabolic inhibition E2-EQ (ge2/l L WSF) 1,0E-08 8,0E-09 6,0E-09 4,0E-09 2,0E-09 0,0E+00 0,7 0,6 Estrogenicity F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 RET Sample DNA-damage Toxic units (TU) ,0E-08 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 RET Sample EROD activity SSF (-1) 0,5 0,4 0,3 0,2 0,1 0,0 F1 F2 F3 F4 F5 F6 Neurotoxicity F7 F8 F9 Sample F10 F11 F12 F13 F14 F15 RET TCDD-EQ (gtcdd/l WSF) 4,0E-08 2,0E-08 No acetylcholine esterase inhibition detected 0,0E+00 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 RET Station 11

12 Comparison of fractions 100 Fraction of added effect (%) Cytotox Metabolic inhib Erod activity Estrogenicity DNA damage Fraction 12

13 Acute toxicity and Estrogenicity Cytotox Estrogenicity Effect (% of all observed) Fraction 13

14 Acute toxicity and DNA damage Cytotox DNA damage 80 Effect (% of all observed) Fraction 14

15 Work tasks ongoing and planned Continuing fish bioassay testing of Photo-oxidized crude oil (UCM-rich) Reference oil (small UCM fraction) Continuing characterization of fractions Preliminary toxicity testing on Calanus nauplii Inhibition of phytoplankton photosystem Physiological status of chlorophyll-containing cells (phytoplankton) PS II Non-destructive testing continuous testing of algal physiological status Pulse-amplitude-modulated (PAM) fluorometry Skeletonema costatum and Isocrysis galbana 15

16 Objectives for The main objective of the activities is to determine the toxic contribution of the unresolved complex mixture (UCM) of petrogenic oils in the marine water column. Determination of potential environmental impacts related to UCM-fractions in biodegraded water-soluble fractions Uptake concentrations and kinetics of UCM in copepods of ecological importance in the Norwegian and Barents Seas (Calanus finmarchicus) The impacts of photo-activation on the toxicity of UCM in a marine copepod UCM-related effects in selected produced waters Data processing and input for exposure (risk) models (OSCAR and DREAM) It is intended that data from this project can be used to include the UCM, or several UCM fractions, as compound group(s) in the exposure models to assess the environmental impacts of the UCM fractions in relation to existing compound groups included in the models. 16