Surface sediment samples (0–10 cm) from ten shallow marine sediments affected by industry and shipping traffic on the northern Atlantic Spanish coast were analysed to determine prevailing concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phthalates and organotins. PAHs were detected at eight of the study areas (1.4 to 4.9 µg g⁻¹), while PCBs were detected only at four of the study areas (2.9 to 37 ng g⁻¹). PAHs concentration rations indicated that PAHs were mainly of pyrogenic origin. PCB congener patterns in all of the sediment samples were the same, and contained the less volatile congeners PCB-138, PCB-153 and PCB-180. Bis(2-ethyl hexyl)phthalate was the most abundant phthalate (190 to 2,600 ng g⁻¹). Total organotin concentrations varied widely from 7.7 to 489 ng g⁻¹. A significant correlation was found between PAH concentrations and sediment particle sizes (p<0.001). Peak concentrations of organotins have the potential to induce ecotoxicological impacts based on levels specified in international Sediment Quality Guidelines, although the majority of the stations analysed are included in the medium-low range of priority.