Research Product

The reef-building coral Montastrea annularis was exposed continuously to suspensions of drilling fluids in flowing seawater at the U.S. Naval Stage I platform. After a 6-week exposure, coral fragments with a surface area of 30-60 cm2 were broken off, rinsed in seawater, and extracted in a one-phase chloroform-methanol seawater extract. They were then returned to the laboratory, where extraction was completed and where the lipids were analyzed for their phospholipid content, aklyl fatty acid composition, and neutral lipid triglyceride glycerol. The aqueous phase was analyzed for free amino acid composition. Biochemical evidence of stress was reflected in the cessation of growth as measured in depressed levels of diacyl phospholipid. Analysis of the acyl fatty acid composition showed changes in polyenoic fatty acids, suggesting possible changes in the metabolism of the fatty acids induced by the exposure to the drilling fluids. There was no significant effect on the level of triglycerid glycerol. The coral also showed increased concentrations of the free aspartic acid and a dose-response-related decrease in the concentrations of free glutamic acid with exposure.