title: Spatial distribution and quantification of endocrine-disrupting chemicals in Sado River estuary, Portugal.
abstract: The important Portuguese Sado River estuary has never been investigated for the presence of potentially endocrine-disrupting chemicals (EDCs), such as natural estrogens (estradiol, estrone), pharmaceutical estrogens (17alpha-ethynylestradiol), phytoestrogens (daidzein, genistein and biochanin A), or industrial chemicals (4-octylphenol, 4-nonylphenol, and bisphenol A). Thus, the main objective of this study was to evaluate their presence at 13 sampling points distributed between both the industrial and the natural reserve areas of the estuary, zones 1 and 2, respectively. For that, water samples collected in summer and winter were processed by solid phase extraction and analyzed by high-performance liquid chromatography with photodiode array detection and gas chromatography-mass spectroscopy. Results showed that estrone, ethynylestradiol, all the aforementioned phytoestrogens as well as bisphenol A and 4-octylphenol were found in zone 1. In zone 2, neither estrogens nor 4-OP were found. However, in the same zone, daidzein (500 ng/L) and genistein (320 ng/L) attained their highest levels in summer, whereas biochanin A peaked in winter (170 ng/L). Furthermore, bisphenol A was also found in some areas of zone 2, but showed similar concentrations in both surveys (about 220 ng/L). This study demonstrated that the Sado River estuary had low EDCs levels, suggesting that the Sado's high hydrodynamic activity may be involved in the dilution of local pollution. It was suggested that at the current levels of concentrations, all assayed EDCs are unlikely to individually cause endocrine disruption in local animals. However, under a continuous exposure scenario, an additive and/or synergistic action of the estrogenic chemicals load can not be excluded, and so, continuous monitoring is advisable.
authors.affiliation: Department of Pharmaceutical Sciences, Superior Institute of Health Sciences-North, Rua Central de Gandra, 1317, 4585-116, Gandra PRD, Portugal.
authors.forename: Cláudia
authors.initials: C
authors.lastname: Ribeiro
authors.forename: Miguel Angelo
authors.initials: MA
authors.lastname: Pardal
authors.forename: Maria Elizabeth
authors.initials: ME
authors.lastname: Tiritan
authors.forename: Eduardo
authors.initials: E
authors.lastname: Rocha
authors.forename: Rui Miguel
authors.initials: RM
authors.lastname: Margalho
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Rocha
mesh_terms: D001559:Benzhydryl Compounds; D052244:Endocrine Disruptors / Q000032:analysis*; D004784:Environmental Monitoring; D019833:Genistein / Q000032:analysis; D010636:Phenols / Q000032:analysis; D048789:Phytoestrogens / Q000032:analysis; D011174:Portugal; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D052244:Endocrine Disruptors; D019833:Genistein; D010636:Phenols; D048789:Phytoestrogens; D014874:Water Pollutants, Chemical; C006780:bisphenol A; D000098826:Bisphenol A Compounds; C004541:biochanin A