| Summary: | This study evaluated the dietary uptake kinetics and sublethal toxicity of p,p′-dichlorodiphenyl dichloroethylene (p,p′-DDE) in Antarctic krill. The uptake rate constant (characterised by the seawater volume stripped of contaminant sorbed to algae) of 200 ± 0.32 mL g wet weight h, average absorption efficiency of 86 ± 13% and very low elimination rate constant of 5 × 10 ± 0.0031 h demonstrate the importance of feeding for p,p′-DDE bioaccumulation in Antarctic krill. Faecal egestion of unabsorbed p,p′-DDE of 8.1 ± 2.7% indicates that this pathway contributes considerably to p,p′-DDE sinking fluxes. A median internal effective concentration (IEC50) of 15 mmol/kg lipid weight for complete immobility indicates baseline toxicity and that Antarctic krill exhibit comparable toxicological sensitivity as temperate species under similar 10 d exposure conditions. These findings support the critical body residue approach and provide insight to the role of Antarctic krill in the biogeochemical cycling of p,p′-DDE in the Southern Ocean.
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