Improved cleanup technique for estimation of endosulfan residues from fish tissues under tropical conditions.

A new solvent system 1% and 2% acetone in hexane, was developed for chromatography on partially inactivated Florisil to facilitate the separation of isomers of endosulfan and its metabolites from fish tissues under tropical conditions. By using the colorimetric method of Maitlen et al. (1963), the minimum detectable limit for each isomer of endosulfan in various fish tissues is 5 micro g. With this solvent system, the 2 isomers present in the technical material can be separated, so their toxicity to fish can be assessed separately.