Stability of 2,3,7,8,-substituted polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran isomer standard solutions

Abstract Cambridge Isotope Laboratories and Radian Corporation have been supplying Analytical Reference Standards of polyhalogenated dibenzo-p-dioxin and dibenzofurans to government, industrial and research laboratories since 1982. A study to establish the long term stability of these isomers in solution has been undertaken. Standard solutions of the seven 2,3,7,8-substituted polychlorinated dibenzo-p-dioxin isomers and ten 2,3,7,8-substituted polychlorinated dibenzofuran isomers were prepared in n-Nonane solution according to rigorous quality control procedures. Standard solutions were then flamed sealed in amber ampules, stored at room temperature and protected from light. Chemical degradation of the compounds was determined by comparison of GC response of a freshly prepared standard with that of the previously prepared solution. The stability study involves solutions that have been stored a minimum of two years. The study indicated that no measurable degradation has occurred when stored at room temperature in amber ampules.