Origin And Distribution Of Polycyclic Aromatic Hydrocarbon Pollution In Sediment And Fish In The Biosphere'S Reserve Of Urdaibai (Bay Of Biscay, Basque Country, Spain)

International audienceThe Urdaibai estuary is an UNESCO's biosphere reserve impacted by recreational, agricultural and industrial activities. Polycyclic aromatic hydrocarbons (PAHs) are major pollutants in Urdaibai, and their control and the identification of their sources is central on the preservation of the area. Chemical analysis by GC-MS showed a significant pollution by PAHs in Urdaibai sediment samples, mainly from pyrolytic sources, with minor contributions from oil spills. Measurement of the dioxin-like activity using a yeast-based bioassay showed an excess of biological activity in sediment samples from the inner part of the estuary. Analysis of PAH metabolites in bile of thicklip grey mullet () showed a large excess of 2-naphthol over 1-naphthol or 1-pyrenol, suggesting a specific contamination in the inner Urdaibai estuary by some industrial process. Therefore, the combination of these three techniques defined different PAH pollution sources in Urdaibai: A major pyrolytic origin, occasional oil spills, and specific industrial activities

An integrated study of endocrine disruptors in sediments and reproduction-related parameters in bivalve molluscs from the Biosphere’s Reserve of Urdaibai (Bay of Biscay)

Urdaibai was declared a Biosphere’s Reserve by UNESCO in 1984. Because we observed a high prevalence of hermaphroditism in mussels sampled in Urdaibai in March 2004, we started the present research work in order to determine the presence of endocrine disruptors (EDs) in sediments and to study possible EDs effects on mussels and oysters using gonad index and vitellogenin (VTG)-like protein levels as biomarkers. Samples were collected at five localities in April 2007 and 2008, and in October 2007. Estrogenic hormones were not detected in sediments and levels of bisphenol A and organotin compounds were very low. Alkylphenols were found at moderate levels and showed a time-dependent decrease. Phthalates were found at levels up to 8000 ng/g. High prevalence of oocyte atresia and necrosis occurred in mussels sampled in April. Retarded gametogenesis was observed in an oyster population from a shipyard. Hermaphrodites or alterations in VTG-like protein levels were not found but the high prevalence of histopathological alterations in oocytes is of concern.Work supported by Catedra UNESCO of the UPV/EHU through the project DERBiUr (UNESCO06/19) and by the Basque Government through project ETORTEK-IMPRES and a grant to consolidated research groups (GIC07/26-IT-393-07).Peer reviewe

An integrated study of endocrine disruptors in sediments and reproduction-related parameters in bivalve molluscs from the Biosphere’s Reserve of Urdaibai (Bay of Biscay)

Urdaibai was declared a Biosphere’s Reserve by UNESCO in 1984. Because we observed a high prevalence of hermaphroditism in mussels sampled in Urdaibai in March 2004, we started the present research work in order to determine the presence of endocrine disruptors (EDs) in sediments and to study possible EDs effects on mussels and oysters using gonad index and vitellogenin (VTG)-like protein levels as biomarkers. Samples were collected at five localities in April 2007 and 2008, and in October 2007. Estrogenic hormones were not detected in sediments and levels of bisphenol A and organotin compounds were very low. Alkylphenols were found at moderate levels and showed a time-dependent decrease. Phthalates were found at levels up to 8000 ng/g. High prevalence of oocyte atresia and necrosis occurred in mussels sampled in April. Retarded gametogenesis was observed in an oyster population from a shipyard. Hermaphrodites or alterations in VTG-like protein levels were not found but the high prevalence of histopathological alterations in oocytes is of concern.Work supported by Catedra UNESCO of the UPV/EHU through the project DERBiUr (UNESCO06/19) and by the Basque Government through project ETORTEK-IMPRES and a grant to consolidated research groups (GIC07/26-IT-393-07).Peer reviewe

Endocrine disruption in thicklip grey mullet (Chelon labrosus) from the Urdaibai Biosphere Reserve (Bay of Biscay, Southwestern Europe)

Endocrine disruptors (EDs) interfere with the development and functioning of the endocrine system, causing reproductive disturbance in aquatic wildlife. The aim of the present work was to determine the presence of EDs in sediments and to investigate possible exposure and effects of EDs in the estuary of the Urdaibai Biosphere Reserve (Gernika) in comparison with the Arriluze marina. For this, gonad histology, plasma vitellogenin (VTG) protein levels and mRNA levels of vitellogenin (vtg), cyp19 aromatases, estrogen receptor (er) and retinoid X receptor (rxr) were studied in Chelon labrosus. The presence of alkylphenols (APs) in fish bile was also assessed. In sediments, estrogenic hormones were below the detection limit and levels of bisphenol A were very low. In Gernika organotin compounds were low but in Arriluze levels of up to 12 μg/g were found. Moderate levels of APs and phthalate levels of up to 8 μg/g were found in sediments. In fish, a high prevalence up to 33% of intersex gonads was found in Gernika, whereas only one intersex was found in Arriluze. Accordingly, mullets from Gernika showed higher concentrations of APs in bile. VTG protein levels were detected not only in females but also in some undifferentiated, male and intersex fish. mRNA of vtg was detected in one male from Gernika. mRNA of er and rxr showed significant differences between seasons. In conclusion, the present study demonstrated that C. labrosus from the Urdaibai estuary were exposed to EDs and showed clear signs of endocrine disruption.This work was supported by Catedra UNESCO of the University of the Basque Country (UPV/EHU) through the project DERBiUr (UNESCO06/19), by the University of the Basque Country through a grant to the Unit of Formation and Research (UFI 11/37), by the Basque Government through the project ETORTEK-IMPRES and a grant to consolidated research groups (GIC07/26-IT-393-07), and by MICINN through the projects CEMAGUA (CGL2007-64551/HID) and SCARCE (Consolider-Ingenio 2010 CSD2009-00065). Denise Fernandes acknowledges a postdoctoral fellowship (SFRH/BPD/34289/2006) from the Portuguese Fundacao para a Ciencia e Tecnologia (FCT) of the Ministry of Science and Technology of Portugal. The help of Drs. T. Serrano and M.C. Barbero with the examination of gonad preparations is greatly acknowledged.Puy-Azurmendi, E.; Ortiz-Zarragoitia, M.; Villagrasa, M.; Kuster, M.; Aragón Revuelta, P.; Atienza Boronat, MJ.; Puchades Pla, R.... (2013). Endocrine disruption in thicklip grey mullet (Chelon labrosus) from the Urdaibai Biosphere Reserve (Bay of Biscay, Southwestern Europe). Science of the Total Environment. 443:233-244. doi:10.1016/j.scitotenv.2012.10.078S23324444