Determination of 25 EDs in frog and fish tissue by GC-MS (SIM)

A gas chromatography/mass spectrometric assay method was developed for the simultaneous determination of neutral and basic twenty-five endocrine disruptors (EDS) in frog and fish. After homogenization and sonication of 5 2 of sample, purification was achieved in one step with a solid phase extraction procedure using silica gelflorisil. Elution was performed with 50 mL of acetone : n-hexane (I : 9) solution. The eluate was concentrated to approximately 10 muL and dissolved with 100 muL of hexane and analyzed by GC-MS (SIM). The peaks had good chromatographic properties and the extraction of these compounds from sample also gave relatively high recoveries with small variations. Detection limits were 0.1 ng/g for 4-nitrotoluene, benzophenone, hexachlorobenzene, atrazine, malathion, o,p-DDD, o,p-DDT and permethrin, and 0.2 ng/g for heptachlor epoxide, gamma-chlordane, alpha-chlordane, p,p'-DDE, p,p-DDD, cypermethrin and fenvalerate, and 0.3 ng/g for trifluralin, metribuzin, alachlor, dieldrin and p,p'-DDT, and 0.5 ng/g for heptachlor, aldrin and parathion, and 0.7 ng/g for endrin, and 0.8 ng/g for nitrofen. The recoveries were between 33 and 109%. The method was used to analyze twenty-five frogs and forty-six fishes samples caught from various regions in Korea. Benzophenone was detected at concentration of up to 17.2 ng/g in frog or fish. Heptachlor, aldrin, gamma-chlordane, p,p'-DDE, p,p'-DDD, endrin and o,p-DDD were detected at concentrations of 0.7-12.5 ng/g in frog or fish. Also significant levels of dieldrin (up to 22.5 ng/g) were observed. The developed method may be valuable to be used to the national monitoring project of EDS in biota samples.