Abstract: Offshore wind energy is a fast growing sector of renewable energies worldwide. This will change the marine environment and thus, a wide range of environmental impacts of offshore wind farms are subject of current research. Here we present an overview about chemical emissions from corrosion protection systems, discuss their relevance and potential impact to the marine environment, and suggest strategies to reduce their emissions. Corrosion is a general problem for offshore infrastructures and corrosion protection systems are necessary to maintain the structural integrity. These systems are often in direct contact with seawater and have different potentials for emissions, e.g. galvanic anodes emitting substantial amounts of metals. Organic coatings may release organic substances due to weathering and/or leaching. Current assumptions suggest a low environmental impact, but monitoring data is not sufficient to assess the environmental impact of this new source.
T. Kirchgeorg, I. Weinberg, M. Hörnig, Section of Marine Sediments, Department of Marine Science, Federal Maritime and Hydrographic Agency, Hamburg, Germany
R. Baier, M.J. Schmid, Steel Structures & Corrosion Protection Section, Department of Structural Engineering, Federal Waterways Engineering and Research Institute, Karlsruhe, Germany
B. Brockmeyerc, Section of Environmentally Hazardous Substances, Department of Marine Science, Federal Maritime and Hydrographic Agency, Hamburg, Germany
Marine Pollution Bulletin
Volume 136, November 2018, Pages 257-268
doi: 10.1016/j.marpolbul.2018.08.058 
Ecotoxicological characterization of emissions from steel coatings in contact with water
Abstract: In order to prevent corrosion damage, steel structures need to be protected. Coating systems achieve this by the isolation of the steel from its environment. Common binding agents are epoxide and polyurethane resins which harden by polyaddition reactions. In contact with water, various organic substances might be leached out and released into the aquatic environment potentially causing adverse effects. So far, no legal requirements are mandatory for the environmental sustainability of coating systems. To characterize emissions from steel coatings, recommendations for the ecotoxicological assessment of construction products were utilized. Seven different coating systems based on epoxide or polyurethane resins were leached in 8 steps (6 h–64 d), followed by the testing of acute toxic effects on bacteria and algae as well as estrogen-like and mutagenic effects. In addition, chemical analysis by GC-MS was performed to identify potentially toxic compounds released from the coating systems. Two systems tested did not show any significant effects in the bioassays. One coating system caused significant algal toxicity, none was found to cause mutagenic effects. The other coating systems mainly showed estrogenic effects and bacterial toxicity. The effects increased with increasing leaching time. 4-tert-butylphenol, which is used in epoxy resins as a hardener, was identified as the main contributor to acute and estrogenic effects in two coatings. The release mechanism of 4-tert-butylphenol was characterized by two different modelling approaches. It was found that the release from the most toxic coating is not explainable by an elevated content of 4-tert-butylphenol but more likely by the release mechanism that – in contrast to the less toxic coating – is controlled not only by diffusion. This finding might indicate a sub-optimal formulation of this coating system resulting in a less stable layer and thus an increased release of toxic compounds.
Anna Maria Bell, Georg Reifferscheid, Sebastian Buchinger, Thomas Ternes, Federal Institute of Hydrology, Koblenz, Germany
Roland Baier, Section B2 – Steel Structures and Corrosion Protection, Federal Waterways Engineering and Research Institute, Karlsruhe, Germany
Birgit Kocher, Department V3 – Environmental Protection, Federal Highway Research Institute, Bergisch Gladbach, Germany
Volume 173, 15 April 2020, 115525
doi: 10.1016/j.watres.2020.115525