Bestimmung von Estrogenen und endokrin aktiven Phenolen aus wässrigen Matrices im 0.1 - 100 Nanogramm/Liter-Bereich

Abstract

A method for the analysis of phenolic estrogenic active compounds in surface and drinking water in the picogram/liter-range is described in this work. Besides the widely used monomer bisphenol A, 4-tert-octylphenol (4-(1,1,3,3-tetramethylbutyl)phenol) and the technical isomer mixture of 4-nonylphenol, phenolic steroid hormones like the endogenous estrogens estrone, 17-alpha-estradiol, 17-beta-estradiol and the exogenous estrogen 17-alpha-ethinylestradiol were determined in water at the 50 - 200 picogram/L-level. Water samples from 1 L to 5 L were extracted by solid phase extraction (SPE) on a cartridge system containing LiChrolut EN as sorbent.

The phenols and steroids were converted into their pentafluorbenzoylate esters in an extractive derivatisation reaction. The derivatives were then determined by high resolution gas chromatography with negative chemical ionisation mass spectrometric detection HRGC-(CH 4)-NCI-MS in the selected ion mode (SIM). All results were also confirmed by electron capture detection HRGC-ECD.

This highly sensitive and specific method gives a limit of detection (LOD) of 20 pg/L for bisphenol A and 4-tert-octylphenol in drinking water samples and 50 pg/L in STW-effluent, respectively. The LODs for technical 4-nonylphenol, 17-alpha-ethinylestradiol and other estrogens are in the range of 100 pg/L in drinking water to 200 pg/L in STW-effluent, respectively. In all river water samples in Southern Germany, bisphenol A was found in concentrations ranging from 500 pg/L up to 16 ng/L, 4-nonylphenol from 6 ng/L up to 135 ng/L and the steroids from 200 pg/L up to 5 ng/L. In drinking water bisphenol A was found in concentrations ranging from 300 pg/L to 2 ng/L, 4-nonylphenol from 2 ng/L to 15 ng/L, 4-tert-octylphenol from 150 pg/L to 5 ng/L and the steroids from 100 pg/L to 2 ng/L. Mean recoveries over the whole analytical protocol, measured in bidistilled water, generally exceeded 70 %.