Spills of crude oil and various refined fractions are an increasing threat to organisms both in marine and in freshwater situations. The present study is concerned with the effects of aqueous crude oil extracts and naphthalene on one organism, the green flagellate Chlamydomonas angulosa, grown under controlled conditions. Tests were carried out under conditions allowing relatively free evaporation and volatilization of the hydrocarbons (open systems) and in closed systems in which hydrocarbon loss was minimized (closed systems).In open systems, 61% of the Chlamydomonas angulosa cells were killed when saturated naphthalene was initially present in the medium. The generation time of the survivors was, however, the same as the controls. In a closed system a much higher percentage of the cells was killed, but a shorter generation time was observed when growth resumed. A prolonged lag phase was characteristic of all naphthalene treatments.The effect of aqueous extracts of crude oils was also tested using different crude oils, fresh and aged extracts, as well as open and closed systems. Extracts were almost always inhibitory, but the effects were less severe than those obtained with naphthalene. The possible implications are discussed.

No abstract

No abstract

No abstract

No abstract