Alkanes in plankton from the Buccaneer oil field

Abstract

From the Conclusions: “BLUMER et al. (1963, 1964) have reported the presence of pristane in relatively high concentrations in several copepods and have suggested that this compound has a role in the maintenance of buoyancy by these organisms. A number of unsaturated hydrocarbons have also been reported in zooplankton (BLUMER and THOMAS 1965, BLUMER et al. 1970). The major n-alkane in a sample of mixed zooplankton and phytoplankton from Tarpaulin Cove, Massachusetts was n-heptadecane, and lower concentrations of other C14 to C29 n-alkanes were found (CLARK and BLUMER 1967).

We have found pristane and other biogenic alkanes in each sample examined. The presence of large amounts of C18 to C37 alkanes in sample XIV is believed to be good evidence for petroleum contamination (MIDDLEDITCH et al. 1977). A similar distribution of alkanes is observed in several other samples.

In summary, one (XIV) of the nine samples from the center of oilfield was heavily contaminated with oil, two (XIII, XIV) were slightly contaminated, and another two (Vl, VII) may have been contaminated. There is some evidence that two (V, XI) of the seven samples collected at distances of 10-15 km from the oilfield contained petroleum alkanes.

Further work is required to determine which species of plankton preferentially ingest the oil and whether they have a role in the dispersion of oil discharged from the production platforms by (i) incorporation into fecal pellets which sinkn to the ocean floor, or ( i i ) transport away from the region of the oilfield.”