Measuring the potential activity of hydrocarbon-degrading bacteria.

[14C]hydrocarbons were utilized as a means of estimating the hydrocarbon-degrading potential of bacteria in estuarine and marine environments. Evaporation of the hydrocarbons must be considered in estimates of oxidation. Amount of mineralization of [14C]hexadecane can be equated with the total number of petroleum-degrading bacteria and the percentage of the total heterotrophic population, which they represent. Mineralization activity was found to be related to the activity of the bacterial populations during in situ incubation. Rates of mineralization were observed, as follows, for [14C]hexadecane greater than [14C]naphthalene greater than [14C]toluene greater than [14C]cyclohexane. Increased rates of uptake and mineralization were observed for bacteria in samples collected from an oil-polluted harbor compared with samples from a relatively unpolluted, shellfish-harvesting area, e.g., turnover times of 15 and 60 min for these areas, respectively, using [14C]hexadecane.