M3 PM Wastewater Treatment: Analysis, Fate and Removal of Emerging Contaminants
Monday, 14 November 2005: 1:50 PM - 5:30 PM in Ballroom 3

(HER-1117-794834) Assessment of estrogenic activity in sewage treatment plant by combining chemical analysis and in-vitro bioassay.

Hernandez-Raquet, G¹, Rabenoelina, F², Muller, M¹, Delgenès, N¹, Patureau, D¹, Balaguer, P², ¹ INRA - Laboratoire de Biotechnologie de l'Environnement, Narbonne, France² INSERM - Laboratoire d'Endocrinologie Moléculaire et Cellulaire de Cancers, Montpellier, France

ABSTRACT- It is generally observed that steroid hormones and nonylphenols (NPE) are present in urban wastewater. These compounds are the main responsible of the estrogenic activity detected in sewage-treatment plants effluents. Hormones and NPE exert physiological effects at concentrations as low as 0.1ng/L and 14g/L, respectively. In order to assess the contribution of hormone and NPE to the total estrogenic potency, we realised chemical analysis and estrogenicity in-vitro tests (MELN) in samples taken at different stages of a sewage treatment plant in France. Solid-phase extracted water samples were analysed by gas chromatography coupled to mass spectrometry to quantify natural and synthetic estrogens. The five estrogens investigated were estrone, 17-estradiol, estriol, 17-ethinylestradiol and mestranol; we also analysed their corresponding sulfate and glucuronide conjugates. Nonylphenol, nonylphenolmono and di-ethoxilates were analysed by liquid chromatography with fluorescence detection. In the same extracts, estrogenicity was determined using MELN cell lines. In three different campaigns, at two different periods of the year, both hormones and estrogenicity measurements decreased markedly as wastewater progressed through the plant : total removal rates were higher than 90%. The final effluent contained estrone, estradiol and ethinylestradiol at concentrations of 1.7-16, <0.5-3 and <0.5-20 ng/L, respectively. NPE concentration were lower that the limit of detection in both influents and effluents, this is probably the result of adsorption onto the solids. Very low levels of estrogenic activity were found in the treated effluent. Expected estrogenicity was estimated from the chemical data for each sample by using the principle of concentration additivity. In this presentation we will consider theoretic estrogenic activities to assess the contribution of each compound to the total measured estrogenicity. Overall, our results suggest that natural and synthetic hormones are responsible of the observed estrogenicity.

Key words: estrogenic activity, steroids, nonylphenols, sewage treatment plant