N-Methylperfluorooctanesulfonamidoethanol-d4, is the labeled analogue of N-Methylperfluorooctanesulfonamidoethanol (M327345), a derivative of Perfluorooctanesulfonamide (FOSA) (P286245), which represents an important subgroup of the environmental contaminants known as perfluorinated compounds (PFCs).