Phosphatidylethanol (PEth) is formed primarily in the liver by transphosphatidylation of phosphatidylcholine (PC) by phospholipase D. PEth is associated with lipoprotein particles VLDL and HDL, transferred between lipoproteins, and PEth-lipoprotein complexes may have a protective effect against atherogenesis by promoting VEGF secretion by SMC and endothelium. Most PEth (about 75%) is incorporated into erythrocyte membranes, and is the longest-lived circulating EtOH metabolite yet identified. NBD-Phosphatidylethanol (NBD-PEth) is a novel flourescent phospholipid analog of this intriguing and rare lipid found in nature.