The Effects of Diesel Fuel on the Growth of Selected Freshwater Phytoplankton

Abstract

The objectives of this investigation were to assay the effects of water extracts of diesel fuel and selected components of diesel fuel on selected species of freshwater algae. The effects of bacterial degradation products of the diesel fuel were also tested. Results of the investigation indicate that under specific culture conditions two of the algae, Chlamydomonas and Scenedesmus, appeared enhanced by the water extract. Selenastrum was unaffected by the water extract and Anabaena was temporarily inhibited, but recovered after the initial lag in growth. The three hydrocarbons heptadecane, hexadecane and nonadecane had varying effects on the algae. Heptadecane inhibited Chlamydomonas , but stimulated Scenedesmus. It had no effect on the other two algae. Nonadecane only affected Chlamydomonas, which was inhibited. Hexadecane slowed the growth of Anabaena , but appeared to stimulate Chlamydomonas. It had no effect on the other two algae. The additional experiments with the bacterial degradation products of the diesel fuel indicated that any inhibitory effect was alleviated by the bacterial action and some enhancement of growth occurred.