Optimisation of analytical method for estrogen in surface water and primary risk assessment in South Creek

A very non-polar sorbent, polystyrene-divinyl-benzene (brand: biobeads supplied by BioRad, with 30¡­50 mesh) was tested for its extraction efficiency of four target compounds, estrone, estradiol, ethynylestradiol and estriol, from larger volumes (8 l) of water samples. To achieve adequate sensitivity of instrumental analysis by GC/MS, an improved estrogen derivatisation method was developed.