CHEMOMETRICAL EVALUATION OF THE PAH CONTAMINATION IN THE SEDIMENTS OF THE GULF-OF-LION (FRANCE)

The concentrations of fluorene, dibenzothiophene, phenanthrene, anthracene, retene, fluoranthene, pyrene, chrysene, triphenylene, benz[a]anthracene, benzo[k]fluoranthene, benzo[a]fluoranthene, benzo[b]fluoranthene, benzo[j]fluoranthene, benzo[e]pyrene, benzo[a]pyrene, perylene, indeno[1,2,3-c,d]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, 1-methylfluorene, 2-methylfluorene, 3-methylfluorene, 4-methylfluorene, 1-methyldibenzothiophene, 2-methyldibenzothiophene, 3-methyldibenzothiophene, and 4-methyldibenzothiophene were measured in superlayer and underlayer deep sea sediments at 15 different sampling sites in the Gulf of Lion (Mediterranean Sea, France). The level of contamination of these 28 polycyclic aromatic hydrocarbons (PAH) in the sediments of the Rhone river was also recorded for comparative purposes. The results obtained were analyzed by means of the nonlinear mapping (NLM) method. A nonlinear map for the samples and another for the chemicals were generated. They were interpreted by means of multiple graphical displays on which were represented various quantitative and qualitative information. From this approach, it was possible to obtain a better knowledge of the PAH contamination of underwater canyons and deep sea fans in the Gulf of Lion. It also allowed the examination of the relationships between the PAH structures and origins and their concentrations in the different samples under study.