Determination of light oil and gasoline on leaf of turfgrass polluted with mineral oils

Two different ways, turfgrass leaf color observation and detection of mineral oils by GC/MS, were applied to determine light oil or gasoline on turfgrass (T-419) after 15hr treatment. In observation of the three color attributes (Hue, Value, Chroma), the turfgrass treated with light oil showed decreased the Value (3.5→2.5) and the Chroma (6→4). Then the leaf color was changed to a dull dark green. In the gasoline treatment, the Value was increased slightly (3.5→4.0), and the Hue was changed to yellowish dark green color (7GY→5GY). It was easy to distingish light oil or gasoline by leaf color observation. Treated leaf samples were analyzed with GC/MS. Light or heavy oil was identified by the pattern of n-alkanes in the light oil treatment. Gasoline was not identified because the main components toluene, xylene, trimethylbenzene, etc. were volatilized