Bioaccumulation of PAHs in marine zooplankton: an experimental study in the copepod Pseudodiaptomus marinus
Résumé
Laboratory exposure experiments were performed on the marine coastal zooplankton species Pseudodiaptomus marinus—a keystone species of vast Atlantic and Pacific marine ecosystems, tracing the accumulation of three polycyclic aromatic hydrocarbons (PAHs): phenanthrene, anthracene and pyrene. The experiment was designed to study the bioconcentration of PAHs in phytoplankton (Rhodomonas baltica) and accumulation in copepods (P. marinus), through two different pathways: food and water uptake. For this purpose, water and organism subsamples were collected, ASE (accelerated solvent extraction) extracted, and analyzed for PAHs by GC/MS technique. As a result, experimental bioconcentration (BCF) and bioaccumulation (BAF) factors which showed a significant correlation with the octanol–water partition coefficient (Kow) were presented for P. marinus. The active feeding route of exposure showed no significant differences versus passive uptake, highlighting the importance of dietary exposure as a major pathway for POPs accumulation in zooplankton; in particular for those which cannot be metabolized.