PARENT SESSION

3B - Marine toxicity evaluation: current practice and applications
Poster Hall
8:30 AM - Monday, 28 April 2003

(MOP/165) Estrogenic potential of the Venice lagoon waters.

Pojana, Giulio¹, Busetti, Francesco¹, Collarin, Anna ¹, Bonfà, Angela ¹, Gomiero, Alessio¹, Marcomini, Antonio¹, ¹ Departement of Environmental Sciences, University of Venice, Venice, Italy

ABSTRACT- There is a growing concern about a range of substances which are suspected of interfering with the endocrine system, so–called endocrine disrupting compounds (EDCs). One chemical exhibits estrogenic potency when causes an estrogen-specific effect in a biological system. The estrogenic potency of a single chemical, compared with that of the estradiol (E2), the known most potent natural estrogen, can be expressed conventionally by its Estradiol Equivalent Factor (EEF). Natural and synthetic hormones, such as estrone and ethinylestradiol, are strong estrogens, in comparison with estrogenic synthetic chemicals such as bisphenol-A and nonylphenol. The latter, however, can occur at concentrations much higher than those of natural estrogens. Successful proofs of the additive behaviour of the estrogenic activity of EDCs mixtures, determined by laboratory experiments, allow the application of the EEF concept also to environmental samples. The estrogenic activity of a water sample can be quantitatively evaluated by determining the EEQ (Estradiol Equivalent Concentration), expressed as pmol/L or ng/L, which is the total amount of the estrogenic active compounds in a sample normalized to the natural estrogen E2. The total content of estrogenic activity of waters from the Venice lagoon (Italy) was assessed by applying a recently developed method allowing the simultaneous determination of natural (estradiol, estrone) and synthetic (nonylphenol, nonylphenol monoethoxylate carboxylate, bisphenol-A, benzophenone, mestranol, ethinylestradiol) EDCs in aqueous environmental samples by HPLC-Ion Trap Mass Spectrometry. The EEQs were between 2.3 and 172 ng/L (median conc.: 24 ng/L), indicating the inflow of estrogenic substances via rivers, municipal and industrial effluents. Steroidal estrogens (17-estradiol, 17-ethinylestradiol) contributed to an extent >99% to the total EEQ.

Key words: Estradiol Equivalent Concentration, endocrine disrupting compounds, HPLC-MS, environment