Guo et al. (2026): Metal bioaccumulation from diatoms to Antarctic krill under ocean alkalinity enhancement with steel slag
Jiaying A Guo, Kerrie M Swadling, Robert F Strzepek, Lavenia Ratnarajah, Scott Meyerink, Rob King, Ashley T Townsend and Lennart T Bach, IN: ICES Journal of Marine Science, https://doi.org/10.1093/icesjms/fsag066
Ocean alkalinity enhancement (OAE) is an emerging carbon dioxide removal (CDR) strategy that utilizes alkaline materials to increase alkalinity in seawater and associated CO₂ storage as bicarbonate. Steel slag is a potential alkaline source material for OAE due to its widespread availability and comparatively high efficiency to enable CDR. However, steel slag also contains trace metals. To assess the risks of metals related to slag-based OAE on marine food chains, the authors conducted a 14-day experiment culturing the diatom Chaetoceros neogracilis and Antarctic krill Euphausia superba under an OAE scenario (+ 30 µmol kg⁻¹ alkalinity). They used a two-factorial design, where slag-treated and control diatoms were fed to krill cultured in slag-treated and control seawater, respectively.