Distributions of three- to seven-ring polynuclear aromatic hydrocarbons on the deep sea floor in the central Pacific

Three- to seven-ring parent and alkylated polynuclear aromatic hydrocarbons (PAHs) are determined in 20 deep sea surface sediments collected along a 175 degrees E transect from 48 degrees N to 15 degrees S. The latitudinal distributions of PAHs except for perylene and retene show that they are low in the low latitudes (15 degrees S-24 degrees N) but remarkably increase from 27 degrees N to 48 degrees N. Concentrations of these PAHs at 48 degrees N are 1-3 orders of magnitude higher than those of the lower latitudes. Similar latitudinal patterns of these PAHs suggest that they were transported as mixtures attached to some aerosol particles but not free forms.