Bioconcentration of selected PAHs in marine phytoplankton: an experimental study.

ANDRES ARIAS; ANISSA SOUISSI; OLIVIER GLIPPA; SOPHIE NET; DAVID DUMOULIN; BAGHDAD OUDANNE; ANA LAURA OLIVA; JORGE MARCOVECCHIO; SAMI SOUISSI

Mar del Plata

Congreso; III Reunión Argentina de Geoquímica de la Superficie (III RAGSU); 2014

Facultad de Cs.Exactas y Naturales - UNMdP

Polycyclic aromatic hydrocarbons (PAHs) are widespread pollutants which have the potential to enter to the marine trophic web, bioaccumulate and biomagnificate. In the present study, by using exclusively laboratory-growth cultures of the marine algae Rhodomonas baltica, PAH?s exposure experiments were run with several replicates and high and ecological sound densities of the algae in order to assess the role of phytoplankton in the marine food web PAH?s uptake process. Then, the algae Rhodomonas baltica was exposed to Phenanthrene, Fluoranthene and Pyrene (concentrations ranging from 113 to 148 ppb) and then the algae and medium were alternatively analyzed for PAHs by means of GC/MS. After several days of exposure the algae exhibited bioconcentration factors up to 45 and experimental Log Koc values which paralleled the literature Koc for particulate sediment, indicating a passive diffusion of the pollutants to the algae. Furthermore, PAH?s exposed algae vs. control algae (clean water) showed decreased population biomass after three days in culture, thus modifying its normal growth kinetics. Results highlight the critical role and sensitiveness to hydrophobic pollutants of the marine phytoplankton, which function as a principal sorbent matrix were the partition equilibrium occurs and one of PAH?s main access points to the food web.