Effects and uptake and excretion kinetics of 11 selected PAHs in Arctic lipid rich copepods

Increased ice cap melting is opening up new areas in the Arctic to human activities such as oil exploration. Offshore oil production releases large quantities of hydrocarbons into the marine environment, notably as produced water and oil droplets. The PWC-Arctic project endeavors to assess the potential environmental impact of oil exploration in the High North by quantifying the uptake and excretion kinetics of selected produced water components and oil droplets and their effects on growth, development and reproduction of the Arctic copepods Calanus glacialis and C. hyperboreus. These calanoids are key zooplankton species with high lipid content, which makes them prone to uptake and accumulation of lipophilic oil components. Particular focus is on bioaccumulation kinetics, oil component transfer, effects on respiration, growth, fertility and fecundity. Experimental findings suggest that the physiological effects of short term exposure to environmentally relevant concentrations of 11 selected polyaromatic hydrocarbons (PAHs) are minor. However, several of the heavier PAHs such as fluoranthene, pyrene and chrysene showed up to approximately 100 % retention after a 120 h depuration period. This slow depuration of PAHs in lipid rich Arctic copepods indicates that stored produced water components may be more available for transfer to progeny and to higher trophic levels than previously anticipated. Acknowledgements: The present work is funded by the Research Council of Norway (project no. 243923/E40 (PWC-Arctic)). The authors would like to thank Drs. Piero Gardinali and Kathia Sandoval of the Department of Chemistry and Biochemistry, Florida International University, FL, USA for the procurement of PAH-spiked mineral oil.