Nonylphenol and 4-tert-octylphenol in the Gulf of Gdansk coastal zone

The concentrations of nonylphenol and 4-tert-octylphenol were measured in surface waters in the Gulf of Gdansk coastal zone (summer 2010). The mean concentration in the samples of subsurface water were 34.49 ng dm-3 (nonylphenol) and 3.04 ng dm-3 (4-tert-octylphenol). The highest nonylphenol concentrations were detected in the samples of subsurface water collected from the Sea Boulevard (Gdynia) while the highest concentrations of 4-tert-octylphenol were found in the yacht harbor Marina Gdynia, and in the Kacza and Gizdebka rivers. A significant enrichment (13-45 times) of 4-tert-octylphenol was observed in the surface microlayer of water. These levels exceeded the predicted no effect concentration by 2-9 times.