Effekter av borreslam: Metaller fra borreslam:

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1 Effekter av borreslam: Er ilmenitt mindre skadelig enn barytt? Metaller fra borreslam: Utlekking fra partikler & opptak i dyr Input til ERMS IRIS-Biomiljø v/renée Katrin Bechmann

2 Exposure system Stirrer Header tank: Mud + seawater Peristaltic pump Ilmenite (titanium-iron oxide) used as weighting material in drilling mud Seawater 3 ml/min Mud 12 ml/min 8-12 h continuous feeding of bivalves with algae Bentonite = clay (hydrated aluminum silicate) also used in drilling mud Circulation pump Mussels Scallops and scallops

3 Mean NRRT (minutes) Lysosomal membrane stability: A general stress response in blood cells Barite mud mg/l ilmenite mud Mean 14.5 mg/l 14 4 mg/l ilmenite mud Bentonite Ilmenite 2 mg/l 2 mg/l 2 mg/l ilmenite mud Barite Metals weeks 3 weeks 1 weeks Recovery Exposure time Jan Fredrik Børseth

4 Mean NRRT (minutes) Lysosomal membrane stability: A general stress response in blood cells Barite mud ilmenite mud Mean 14.5 mg/l 14 Bentonite 37 mg/l mg/l 2 mg/l Barite 23 mg/l 8 Ilmenite 32 mg/l.5 mg/l mg/l 4 Metals 4 2 mg/l weeks 3 weeks 1 weeks Recovery Exposure time Jan Fredrik Børseth

5 Mean NRRT (minutes) Lysosomal membrane stability: A general stress response in blood cells Barite mud ilmenite mud Mean 14.5 mg/l 14 Bentonite 37 mg/l Ilmenite 32 mg/l mg/l 2 mg/l mg/l 8 Barite 23 mg/l 8 2 mg/l mg/l 4 Metals weeks 3 weeks 1 weeks Recovery Exposure time Jan Fredrik Børseth

6 Summary of results from analysis of NRRT Mean NRRT (minutes) Mean Bentonite 37 mg/l Ilmenite 32 mg/l mg/l mg/l 2 mg/l Ilmenite mud weeks 1 weeks Recovery Exposure time Jan Fredrik Børseth

7 -How efficiently can scallops filter food (algae) from the water when they have been exposed to drilling mud for 1 weeks? Sampling times (minutes) X 7

8 Percent algae left - How efficiently can scallops filter food (algae) from the water when they have been exposed to drilling mud for 1 weeks? Mean of 14 control scallops from 24 and 1 control scallops from 27 kept for 1 weeks in the experiment Feeding time (minutes)

9 Percent algae left Filtration efficiency of scallops after 1 weeks drilling mud exposure Bentonite: No problem 4 37 mg/l Bentonite Bentonite Feeding time (minutes)

10 Percent algae left Filtration efficiency of scallops after 1 weeks drilling mud exposure 1 8 * * * 6 37 mg/l Bentonite Bentonite mg/l Ilmenite Ilmenite Feeding time (minutes)

11 Percent algae left Filtration efficiency of scallops after 1 weeks drilling mud exposure 1 8 * * * 6 4 * Bentonite 37 mg/l Bentonite 32 mg/l Ilmenite Ilmenite 2 * 2 mg/l used ilmenite mud High IL-mud Feeding time (minutes)

12 Percent algae left Filtration efficiency of scallops after 1 weeks drilling mud exposure * * * * * Barite 37 mg/l Bentonite Bentonite 32 mg/l Ilmenite Ilmenite Barite particles reduce 2 mg/l used High IL-mud filtration ilmenite mud more than ilmenite particles 23 mg/l Barite Barite Ilmenite Feeding time (minutes)

13 Percent algae left Filtration efficiency of scallops after 1 weeks drilling mud exposure 1 * * * * * Used Barite Mud Bentonite 37 mg/l Bentonite Used barite mud reduce Ilmenite 32 mg/l filtration Ilmenite more than used ilmenite mud 2 mg/l used High IL-mud ilmenite mud Barite 23 mg/l Barite 2 mg/l used barite mud Used Ilmenite mud High BA-mud Feeding time (minutes)

14 Percent algae left Filtration efficiency of scallops after 1 weeks drilling mud exposure 1 Used mud (BA) BA Used mud (IL) IL Bentonite Ilmenite Used water based drilling High IL-mud mud reduce filtration more than the weighting material Barite (barite or ilmenite) alone High BA-mud Feeding time (minutes)

15 Mussel larvae Feeding test Thierry Baussant 11 days exposure of mussel larvae to drilling mud 1 day without feeding Add algae (food) 6 Isochrysis/ml 1 hour lunch Remove algae Rest 24 hours Epi-fluorescense analysis of algae inside the mussel larvae to determine efficiency of feeding

16 4 mg/l barite mud 4 mg/l Ilmenite mud 8 mg/l ilmenite % larver med fulle mager 1 mg/l ilmenite mud 2 mg/l ilmenite mud Ilmenite Stage I Combi control Thierry Baussant 1 mg/l barite mud 8 mg/l barite Stage I Stage III 1 Stomac filling 8 Stage II Shell margin 6 Ilmenite caused more effect on feeding in mussel larvae than barite 4 But used water based BA and IL mud caused similar response 2

17 Scallops exposed to drilling mud for 3 weeks: Metal accumulation in gills 23 mg/l Barite: barium (x 1274), lead (x 5), copper (x 1.6) and cadmium (x 1.2) 32 mg/l Ilmenite: nickel (x 3) Barite vs Ilmenite: More metals in/on gills from barite exposed scallops than ilmenite exposed Used water based drilling mud: 2 mg/l Used barite mud: barium (x 458) + lead (x 2) 2 mg/l Used ilmenite mud: barium (x 165), lead (x 2) and nickel (x 2). But used WBM is different Stig Westerlund

18 Metaller fra borreslam: Utlekking fra partikler & opptak i dyr Input til ERMS - Noen smakebiter!

19 Release of metals from the sediment 3 types of experiments: Release of metals during sedimentation Zn Fe Cd Pb Cr Ni Co Cu We have calculated leaching of metals from particles during sedimentation: 1. Shaking experiment ( Worst case ) 2. Sedimentation experiment ( Best case ) 3. We have calculated the flux of metals from different types of drilling mud to seawater

20 Leaching of metals from drilling mud during sedimentation Release of metals during sedimentation Zn Fe Cd Pb Cr Ni Co Cu 2. Påfyll hver uke 1. Shaking experiment 2. Sedimentation experiment Prøvetaging en uke etter siste påfylling av mud, rett før neste batch fylles på

21 Percent metal leached to seawater Leaching of metals from drilling mud during sedimentation Barite WBM Shaking experiment Standard procedure 3 2 Sedimentation experiment Cadmium Lead Copper Nickel Ilmenite WBM Shaking is conservative, but less conservative than expected 4 3 Pb, Cu and Ni leached more from ilmenite mud than from barite mud 2 1 Cadmium Lead Copper Nickel

22 Flux of metals from different types of mud to seawater Release of metals from the sediment Zn Fe Cd Pb Cr Ni Co Cu Flux of metals from different types of drilling mud to seawater

23 Release of metals from the sediment Flux of metals from different types of mud to seawater: µg metal per cm 2 per year Ilmenite-WBM vs Ilmenite Calculated flux of metals from sedimented drilling mud 1 Fe Pb Zn Cd Cr Ni Co Cu 1 Used WBM with ilmenite Ilmenite Cd Pb Cu Ni

24 Release of metals from the sediment Flux of metals from different types of mud to seawater: µg metal per cm 2 per year Barite-WBM vs Barite Calculated flux of metals from sedimented drilling mud 1 Fe Pb Zn Cd Cr Ni Co Cu 1 Used WBM with barite Barite Cd Pb Cu Ni

25 Flux of metals (gram/year) from a 1 meter (diameter) cutting pile BA-WBM IL-WBM Ilmenite Barite Bentonite BA-WBM IL-WBM Ilmenite Barite Bentonite BA-WBM IL-WBM Ilmenite Barite Bentonite BA-WBM IL-WBM Ilmenite Barite Bentonite Kobber (Cu) Kadmium (Cd) Nikkel (Ni) Bly (Pb) Used BA-WBM leached more Cu, Ni and Pb than barite Used IL-WBM leached more Cu, Cd, Ni and Pb than ilmenite

26 Depuration of metals in mussels? 3 weeks exposure to barite (26 mg/l) 3 weeks depuration in clean water Metal analysis of gill, gonad and digestive gland

27 After exposure After depuration Depuration of metals in mussels? After exposure After depuration After exposure After depuration After exposure After depuration After exposure After depuration After exposure After depuration 12 1 Ba 7 6 Pb 4 35 Ba.25.2 Pb 3 25 Ba.8.7 Pb Digestive gland Gonad Gill mg/kg wet weight High metal barite

28 - Food chain effects of exposure to barite? We fed cod with mussels exposed to barite for 3 weeks - Accumulation of metals in cod liver? - Effects (liver histopathology) in cod? Feeding every day for 3 weeks

29 Ba Ba X 111 Pb Pb +3% Cu Cu +3% Low metal barite Low metal barite Treatment Treatment Treatment Low metal barite Exposed Exposed Exposed Zn Zn +3% Low metal barite Cd Cd +6% Low metal barite Treatment Treatment Treatment Hg Hg +3% Low metal barite Exposed Exposed Exposed Metals in mussels exposed to 26 mg/l barite for 3 weeks Increased concentration of Ba, Pb, Cu, Zn, Cd and Hg in the mussels

30 The metal concentrations in cod liver did NOT increase: Ba Ba treatment Zn Feed Pb Pb Cd treatment Feed Cu Cu Hg treatment Feed Zn Feed Cd Feed Hg Feed treatment treatment treatment We are now working with liver histopathology to check for effects

31 En omtrentlig, populistisk og foreløpig oppsummering av de siste 5 års borreslamforskning på IRIS: I av III Et par prosent av metallene i mudden kan lekke ut i vannet; det kan bli endel gram metall fra en kakshaug i løpet av et år. Eksponerte skjell får økte konsentrasjoner av ymse metaller i alle vev. Noen metaller forsvinner etter en periode i rent vann, men ikke alle. Utlekking av metaller og effekter er ikke de samme for brukt vannbasert borreslam (WBM) og vektmaterialet

32 En omtrentlig, populistisk og foreløpig oppsummering av de siste 5 års borreslamforskning på IRIS: II av III Brukt mud ga generelt flere og mer alvorlige biologiske effekter enn barytt, ilmenitt og bentonitt Men her er det untak: f.eks. Minst like tydelig gjelleskade for kamskjell eksponert for bentonitt som brukt ilmenitt mud, og tydelig gjelleskade på torsk eksponert for barytt. Dette tyder sannsynligvis på at effektene ikke bare skyldes fysisk stress, og heller ikke bare metaller, men kanskje kjemikalierester eller kanskje er ulik partikkelstørrelse på vektmaterialet og den brukte mudden avgjørende?

33 En omtrentlig, populistisk og foreløpig oppsummering av de siste 5 års borreslamforskning på IRIS: III av III Brukt baryttmud ga flere og generelt mer alvorlige effekter enn brukt ilmenittmud Etter 3 uker i rent vann var endel skader/responser reparert i kamskjell eksponert for brukt ilmenittmud, men andre responser var fremdeles tydelige Torsk som spiste blåskjell stappfulle av barytt i tre uker tok ikke opp metall i lever Og nå har vi akkurat dratt igang prosjekt med koraller & mud

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