Isomer specific determination of polychlorinated technical mixtures such as polychloronaphthalenes by GC/MS

Summary A procedure has been developed which allows the determination of the concentration and composition of polychlorinated technical mixtures in environmental samples avoiding the use of standard compounds as much as possible. A common MS response of the congeners of each degree of chlorination is assumed and determined by comparison of the FID and MS response of the respective congeners in a technical mixture. A measure for the variability of the assumed common MS response is derived so that its validity is proved in an objective manner. The method presented here allows the isomer specific determination of those polychlorinated technical mixtures in environmental samples which could not so far be determined in this way for lack of standards. The polychlorinated naphthalenes are quoted as illustration and a few data of residues in environmental samples are given.