Subsurface degradation of fuel oil spills can be estimated by examining the ratios of C17/pristane and C18/phytane.¹ To assist in identifying these four compounds from the complex fuel oil analysis, we offer a product that contains these compounds for retention time determination.

¹Interpretation of Gas Chromatographic Data in Subsurface Hydrocarbon Investigations, R. Senn and M. Johnson, Ground Water Monitoring Review, Winter 1987.