Offshore Wind Structures Leach Hazardous Metals into the Marine Environment
A new peer-reviewed study has warned that the rapid expansion of offshore wind farms could be releasing significant quantities of hazardous metals into marine ecosystems, with potential long-term consequences for seabed health and marine species.
The research, published in Marine Pollution Bulletin and conducted by scientists from Bangor University, Imperial College London, and other institutions, examined how materials used in offshore wind infrastructure — including antifouling coatings, galvanic anodes, and corrosion protection systems — leach metals such as copper, zinc, and aluminum into surrounding waters.
The paper notes: “Metals such as copper and zinc are well known for their toxicity to marine invertebrates and fish, with sublethal effects occurring at concentrations only slightly above background.” The authors warn that the expansion of offshore wind without fully accounting for these emissions could pose “a significant chemical pressure on marine ecosystems”.
Large-Scale Release of Contaminants
According to the study, sacrificial anodes used to prevent corrosion of turbine foundations are a major source of metal release. Aluminum-based anodes, often alloyed with zinc, magnesium, and indium, slowly dissolve into the marine environment. The review cites findings that a single offshore wind farm could release several tons of aluminum and zinc over its operational life.
Antifouling paints, applied to prevent marine growth on turbine structures, were also found to leach copper-based biocides. The study highlights that these coatings can “contribute to localized contamination of sediments” and that copper’s persistence in the environment means it can build up in benthic habitats, impacting shellfish, crustaceans, and other bottom-dwelling species.
Data Gaps and Regulatory Challenges
The researchers stress that while offshore wind is promoted as a low-carbon energy source, its full environmental footprint remains poorly understood. “There is a lack of comprehensive data quantifying the cumulative release of metals from offshore wind infrastructure at regional and national scales,” the authors warn that without such information, regulators face challenges in managing environmental risk.
They also note that sediment disturbance from turbine installation and maintenance can re-suspend contaminated particles, increasing the potential for bioaccumulation in marine food webs. This could have implications for both biodiversity and the fishing industry.
Call for Urgent Monitoring
The report calls for urgent and standardized monitoring programs to assess metal emissions from offshore wind farms, along with research into non-toxic alternatives for coatings and corrosion prevention. “With the sector set to grow substantially over the coming decades, addressing these chemical emissions is vital to avoid replacing one environmental problem with another,” the paper concludes.
The findings add to a growing body of evidence suggesting that while offshore wind plays a key role in decarbonization, its ecological impacts must be factored into marine spatial planning and licensing.
This article was originally published on the UK-based website The Fishing Daily (thefishingdaily.com) and was re-published with permission.
