Determination of 2,3,7,8‐tetrachlorodibenzo‐1,4‐dioxin in 2,4,5‐trichlorophenoxyacetic acid and 2,4,5‐T alkyl ester herbicides

Abstract

Abstract A gas chromatographic method for the determination of 2,3,7,8‐tetrachloro‐dibenzo‐1,4‐dioxin in 2,4,5‐trichlorophenoxyacetic acid and 2,4,5‐T alkyl ester herbicides is described. Of 80 samples of 100% 2,4,5‐trichlorophenoxyacetic acid alkyl ester herbicides 25 contained less than 0.05 part/million and 75 less than 0.5 part/million 2,3,7,8‐tetrachlDrodiben2o‐1,4‐dioxin. Of 32 samples of 50% formulations of 2,4,5‐T alkyl esters in mineral oil, 8 contained less than 0.05 part/million and 18 less than 0.5 part/million tetrachlorodioxin. The maximum found was 28.3 part/ million.