Determination of potential toxicity of antifouling coatings to non-target organisms

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1 Determination of potential toxicity of antifouling coatings to non-target organisms Britta Eklund, Jenny Karlsson and Erik Ytreberg Dep. of Applied Environmental Science (ITM), Stockholm University

2 Most boat hulls are repainted each year

3 Fouling by algae

4 Barnacles (Balanus)

5 Effects on non-target organisms Deformations Imposex

6 History of TBT-regulations 1989 TBT prohibited for boats < 25 m 2003 TBT prohibition for application (IMO) 2008, 1 Jan No ships with TBT paint are allowed to port European harbours 2008, Sept A global ban of TBT on all ships is fully enforced (IMO)

7 Small marina A E F G B C D

8 Depth profiles of tin organic substances in sediment from the small marina 20 m from slipway 40 m from slipway 0-2 cm 2-6 cm 8-10 cm 0-2 cm cm MBT DBT TBT µg/kg DW (dry weight) µg/kg DW (dry weight)

9 What is the situation today? Are non-target organisms affected negatively by the new coatings? How do we determine effects on nontarget organisms?

10 Bakgrund Biological tests Gives a direct estimate of toxicity (synergism and antagonism) A valuable complement to chemical analysis

11 the Baltic Sea Low salinity Low biodiversity High sensitivity Particular Sensitive Sea Area (PSSA) in 2004

12 Up to 1000 organisms may be associated to one bladder wrack

13

14 Regulations in Sweden on antifouling paints for use on pleasure boats in1998 No copper and irgarol based paints are today allowed for use on pleasure boats on the east coast. Restrictions for copper leakage on the west coast. Full enforcement 1st of January 2001

15 Today No copper and irgarol based paints are today allowed for use on pleasure boats on the east coast. biocide-free paints Restrictions for copper leakage on the west coast. biocide containing paints for pleasure boats and for ships

16 Experiments A. biocide free paints toxicity tests B. release rates of Cu and Zn in artificial and natural sea water C. ship paints toxicity tests

17 Method - leaching procedure 10 cm2 1 L 7 ASW or NSW Shaking table 14 days

18 Test organisms Relevant organisms for the Baltic Sea and marine environment Salinity range 0 32 Ceramium tenuicorne Red macroalga Length ~10 cm Nitocra spinipes Harpacticoid copepod Meiobenthic Length mm

19 Growth inhibition test with Ceramium 4 replicates/conc. Test conditions Incubation: 7 days Daily rythm: 14h L: 10 hd Temperature: 22 C±2 C Salinity: mm

20 Ceramium growth inhibition test Ceramium tenuicorne The increase in length after 7 days of exposure is measured EC 50 = The concentration where the growth rate is inhibited 50 % compared to the control

21 The Ceramium growth inhibition test is on its way to become an ISO standard (ISO/FDIS 10710)

22 Nitocra lethality test SS (adults) Nitocra spinipes crustacean ca 0,8 mm Method Determination of mortality after 96 h exposure LC50 is calculated

23 Larval development ratio (LDR) Starting with females carrying egg-sack

24 Method - Larval development ratio (LDR) Nauplii (6 stages) Copepodite (5 stages + the adult)

25 What is larval development ratio (LDR)? DAY 0 DAY 6-9 newborn nauplii copepodites nauplii copepodites Larval development ratio = * 100 nauplii + copepodites

26 Method -Larval Development Ratio (LDR) ~300 gravid females 8 replicates/conc. Test terminated: ~50 % of the total numbers of copepods in the control have reached a copepodite stage (~6 days)

27 Experiments A. biocide free paints toxicity tests B. release rates of Cu and Zn in artificial and natural sea water C. ship paints toxicity tests

28 New physically working paints SSC-44 Reference paint Cu & irgarol

29 Resultat och diskussion Ranking of biocid free coatings Paint Micron Eco SSC-44 Cruiser Sup. Cruiser Eco Lefant SPF Mille Light Lefant H2000 Vc17mEco Aurora VS721 SafeBoatSkin EcoMar2000 Function Polishing Scale structure Copper and irgarol Polishing Polishing Polishing Polishing Teflon Wax Polymer wax Capsaicin Biocid free Prohibited Chemical leaking

30 Method - leaching procedure 10 cm2 1 L 7 ASW or NSW Shaking table 14 days

31 The ranking procedure Ceramium Nitocra acute EC50 points LC50 points

32 Resultat och diskussion Ranking of biocid free coatings Paint Function Total points Micron Eco Polishing 640 SSC-44 Scale structure 640 Cruiser Sup. Copper and irgarol 544 Cruiser Eco Polishing 264 Lefant SPF Polishing 144 Mille Light Polishing 48 Lefant H2000 Polishing 48 Vc17mEco Teflon 4 Aurora VS721 Wax 4 SafeBoatSkin Polymer wax 4 EcoMar2000 Capsaicin 4 Biocid free Prohibited Chemical leaking

33 Results after testing eleven antifouling paints The new restrictions have lead to several new non toxic paints. Some of the paints leak toxic substances and some were even more toxic than the prohibited reference paint.

34 Regulations Only products containing biocides need an approval. Non biocide containing products only need to be registered. Only ingredients above 1 weight-% has to be declared.

35 Experiments A. biocide free paints toxicity tests B. release rates of Cu and Zn in artificial and natural sea water C. ship paints toxicity tests

36 Resultat och diskussion Experiment B, - release rates of Cu and Zn in artificial and natural seawater Paint Active substance Area of use Antifouling Ol. Cu Ships Interspeed 617 Cu Ships Fabi Cu Pleasure boats, West coast Micron Eco non Pleasure boats, east coast Mille Light non Pleasure boats, east coast Ship Cu leakage Pleasure boat Cu leakage Pleasure boat Biocide free

37 Concentrations of Cu in anti-fouling leachates A) Cu concentration in ASW B) Cu concentrations in NSW Cu (µg l -1 ) Cu (µg l -1 ) Leaching time (days) Leaching time (days) Ship Cu leakage Pleasure boat Cu leakage Pleasure boat Biocide free

38 Concentrations of Zn in anti-fouling leachates C) Zn concentration in ASW D) Zn concentrations in NSW Zn (µg l -1 ) Zn (µg l -1 ) Leaching time (days) Leaching time (days) Ship Cu leakage Pleasure boat Cu leakage Pleasure boat Biocide free

39 Resultat och diskussion Leakage rates Artificial seawater Natural seawater Copper Zinc Leakgae rate (µg/cm 2 /day) Leakgae rate (µg/cm 2 /day) Artificial seawater Natural seawater no organic material organic material

40 Resultat och diskussion Experiment B, ship/pleasure boat paints Paint Cu (µg cm -2 d -1 ) ASW Cu (µg cm -2 d -1 ) NSW Zn (µg cm -2 d -1 ) ASW Zn (µg cm -2 d -1 ) NSW Antifouling Ol Interspeed Fabi Micron Eco Mille Light Ship Cu leakage Pleasure boat Cu leakage Pleasure boat Biocide free

41 Resultat och diskussion Experiment B, - release rates of Cu and Zn in artificial and natural seawater Paint Active substance Zinc oxide Area of use Antifouling Ol. Copper oxide (39%) % Ships Interspeed 617 Copper oxide (56%) 2.5-<10% Ships Fabi Copper oxide (6%) 10-25% Pleasure boats West coast Micron Eco non 25-<50% Pleasure boats east coast Mille Light non 25-50% Pleasure boats east coast Ship Cu leakage Pleasure boat Cu leakage Pleasure boat Biocide free

42 Experiments A. biocide free paints toxicity tests B. release rates of Cu and Zn in artificial and natural sea water C. ship paints toxicity tests

43 Resultat och diskussion Experiment C, toxicity of ship/pleasure boat paints Paint Active substance Zinc oxide Area of use Antifouling Ol. Coppar oxide (39%) % Ships Interspeed 617 Coppar oxide (56%) 2.5-<10% Ships Cruiser Sup. Copper thiocyanate (19%), irgarol (3.3%) no info. Pleasure boats. Banned since Fabi Coppar oxide (6%) 10-25% Pleasure boats West coast Micron Eco non 25-<50% Pleasure boats east coast Mille Light non 25-50% Pleasure boats east coast Ship Cu leakage Prohibited Cu and irgarol Pleasure boat Cu leakage Pleasure boat Biocide free

44 Resultat och diskussion Toxicity to the alga Artificial seawater Natural seawater 4 EC50 (% leakage water) Irgarol? 12 µg/l? 0 Antifouling Ol. Interspeed Cruiser superior Fabi Micron Eco EC 50 (Cu): 2-6 µg/l EC 50 (Zn): µg/l

45 Conclusions Biocide free coatings may be more toxic than coatings based on leakage of active substance No large differences in toxicity between coatings intended for use on ships or pleasure boats The release rates of both Cu and Zn is much lower in natural compared to in artificial seawater Biocide free coatings may leak Zn in concentrations that may be toxic to non-target organisms Biological tests are a valuable complement to chemical analysis

46 Publications Karlsson, J., Ytreberg, E., Eklund, B. Toxicity of anti-fouling paints for use on pleasure boats and vessels to nontarget organisms representing three trophic levels. (In press) Environmental Pollution. Eklund, B., Elfström, M., Gallego, I., Bengtsson, B-E., Breitholtz, M. Biological and chemical characterization of harbour sediments from the Stockholm area. (in press) Soil and Sediment Pollution). Ytreberg, E., Karlsson, J., Eklund, B. Comparison of toxicity and release rates of Cu and Zn from anti-fouling paints leached in natural and artificial brackish seawater. (Submitted to Marine Pollution). Eklund, B. Karlsson, J. (In press). Assessing Chemical Risks: Evaluating Products Rather than Substances, and the Case of Anti-fouling Paints. In: Regulating Chemical Risk: Multidisciplinary Perspectives on European and Global Challenges, eds.eriksson, j., Gilek, M., Rydén,C. Eklund, B. Karlsson, J. (In press). Assessing Chemical Risks: Evaluating Products Rather than Substances, and the Case of Anti-fouling Paints. In: Regulating Chemical Risk: Multidisciplinary Perspectives on European and Global Challenges, eds.eriksson, j., Gilek, M., Rydén,C. Eriksson Wiklund, A-K., Vilhelmsson, S., Eklund, B. (2009). Contaminants and competition in the Baltic Sea: behavioural experiments with the native species, Monoporeia affinis and the invasive genus Marenzelleria. Estuarine Shelf and Coastal Science, 82(2), Eklund, B., Elfström, M., Borg, H. (2008). TBT originates from pleasure boats in Sweden in spite of firm restrictions. Open Environmental Sciences, 2, Karlsson, J., M. Breitholtz, Eklund, B. (2006). A Practical Ranking System to Compare Toxicity of Anti-fouling Paints. Marine Pollution Bulletin, 52, Eklund, B. (2005). Development of growth inhibition test with the marine and brackish water red alga Ceramiium tenuicorne. Marine Pollution Bulletin, 50, Karlsson, J., Eklund, B. (2004). New biocide-free antifouling paints are toxic. Marine Pollution Bulletin, 49,