Determination of free and conjugated forms of endocrine-disrupting chemicals in human biological fluids by GC-MS

Background: Humans are exposed to hazardous substances including endocrine-disrupting chemicals (EDCs). These compounds have been associated with some diseases such as cancer and ascribed adverse effects on life-essential organs. Results: The method, which allows the determination of both free and conjugated forms of EDCs, involves the liquid-liquid extraction from the sample with ethyl acetate, followed by its preconcentration and clean-up by SPE in a continuous system for the subsequent determination by GC-MS. The proposed method affords very low LODs and RSD. Conclusion: This allowed its successful application to the determination of EDCs in human urine, blood and breast milk. The most frequently founded were methylparaben, ethylparaben, bisphenol A and triclosan.