Coral metabolic activity, nutritional status and microbial infection with exposure to drilling fluids

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 for 6-weeks. They were then returned to the laboratory, where the lipids were analyzed for their phospholipid content, alkyl 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.