No. 2 fuel oil compound retention and release by Mytilus edulis : 1983 Cape Cod Canal oil spill

Abstract

Retention and release of No. 2 fuel oil compounds by Mytilus edulis contaminated by a small oil spill in the Cape Cod Canal in 1983 has been studied for the population "in situ" and for a subsample transplanted to a clean laboratory seawater system. Compounds analyzed include C13 to C24 n-alkanes; pristane; phytane; C2-, C3-naphthalenes; fluorene; phenanthrene; C1-, C2-, C3-phenanthrenes; fluoranthene; pyrene and dibenzothiophene. Biological half-lives were determined for the compounds from Day-3 to Day-29 following the spill and ranged from 1.5 days for C2-naphthalenes to 9.9 days for C2-phenanthrenes. Biological half-lives for the unresolved complex mixture determined by gas chromatographic analyses were 17 days for the alkane-cycloalkane fraction and 35 days for the aromatic fraction. Results compared favorably with data from a small oil spill contaminating the same mussel population at the same time of the year in 1978, although marked differences were noted for certain parameters. Gas chromatographic-mass spectrometer analyses of C2- and C3-phenanthrenes revealed changes in relative abundance of compounds within isomer groups from samples at Day-29 to the time when no further detection of fuel oil was noted. These results suggest a release or metabolism of these compounds which is molecular structure specific. This study also demonstrated the feasibility of training an analyst unfamiliar with analyses of hydrocarbons in tissues to conduct high resolution glass capillary GC analyses and some aspects of GCMS data systems output within a period of four to five months.