Petroleum in coastal seawater of Gdańsk Bay

The paper presents petroleum concentration in coastal waters of Gdańsk Bay, which was measured in 2006 - 2012. The oil concentration ranges from below the detection limit, i.e. 1 μg kg^-1 to almost 120 μg kg^-1. The concentration does not usually exceed 60 μg kg^-1 and its average value is 11.7 μg kg^-1. The presence of petroleum in coastal water is characterized by seasonality, with the lowest values in summer and the highest in winter. The conducted research showed that the coastal zone is not the source of petroleum contamination of the sea. The main reason for the presence of petroleum in the coastal water is the migration of polluted water within the bay. The inflow of pollutants from the mainland is yet another source of the contamination in the sea.