The US Coast Guard has issued Marine Safety Alert 10-18: U.S. Gulf Coast Bunker Contamination. The alert raises awareness of an emerging problem in the US Gulf Coast Region regarding contaminated vessel fuel oil bunkers. The notice states "The Coast Guard recommends that vessel owners and managers ensure vessel operators are made aware of this potential hazardous condition, closely monitor fuel oil system components and consult their bunker suppliers and other technical service providers regarding this issue." Fuel tester VPS has indientified the presence of 4-Cumyl-Phenol which is used in the manufacture of epoxy resins and as emulsifier in pesticides. Whle the source of contaminiation remains unknown, it is presumed to be associated with the use of fuel oil cutter stocks. The standard fuel oil tests for the ISO 8217 specification will not detect these underlying problems.