The influence of some linear alkanes on the survival of Escherichia coli natural sea water was investigated. Alkanes with fifteen or more carbon atoms induced a large decrease in viability of E. coli cells in natural sea water. In this case and for concentrations higher than 100 ppm, the loss of viability followed an exponential relationship with the carbon chain length. In the presence of 500 mg l-1 heptane, the survival was 1.6 times higher than that of controls. The progressive disappearance of heptane from the survival medium with a low and temporary accumulation by cells, suggests that this alkane may have been responsible for the increase of cell viability.
