Hydrocarbons from sea water

Abstract Dissolved hydrocarbons have been extracted by means of chloroform, from coastal and open sea waters; after isolation of the unsaponifiable fraction and preparative thin-layer chromatography, they were analysed by gas-liquid chromatography and mass spectrometry. Hydrocarbons represent ca. 20% of the total extracts; concentrations may vary from 10 to 140 μg/1. N-Paraffins occur to an extent of ca. 12%, from n-C 14 to n-C 37 , with a maximum at n-C 27 to n-C 30 ; odd carbon paraffins are not predominant. Sea waters of different origins (collected at depths of as much as 4500 metres) show a similar composition in dissolved hydrocarbons; this composition does not differ much from the hydrocarbons usually found in algae. A probable hypothesis is that sea-water hydrocarbons originate from the micro or macro phytoplankton. Coastal waters clearly indicate pollution by hydrocarbons of lower molecular weight or chlorinated hydrocarbons.