title: Photodegradation behaviour of estriol: An insight on natural aquatic organic matter influence.
abstract: Estriol (E3) is one of the steroidal estrogens ubiquitously found in the aquatic environment, photodegradation being an important pathway for the elimination of such endocrine disrupting compounds. However, it is important to understand how environmentally important components present in aquatic matrices, such as organic matter, may affect their photodegradation. The main objective of this work was to investigate the photodegradation of E3 in water, under simulated solar radiation, as well as the effect of humic substances (HS - humic acids (HA), fulvic acids (FA) and XAD-4 fraction) in E3 photodegradation. Moreover, the photodegradation behaviour of E3 when present in different environmental aquatic matrices (fresh, estuarine and waste water samples) was also assessed. Results showed a completely different E3 degradation rate depending on the aquatic matrix. In ultrapure water the half-life obtained was about 50 h, while in presence of HS it varied between 5 and 10 h. Then, half-life times between 1.6 and 9.5 h were determined in environmental samples, in which it was observed that the matrix composition contributed up to 97% for the overall E3 photodegradation. Therefore, E3 photodegradation in the considered aquatic matrices was mostly caused by photosensitizing reactions (indirect photodegradation).
authors.affiliation: Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Cindy
authors.initials: C
authors.lastname: Oliveira
authors.affiliation: CESAM & Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal; Instituto Politécnico de Coimbra, ESTESC-Coimbra Health School, Complementary Sciences, Rua 5 de Outubro, S. Martinho do Bispo, 3046-854 Coimbra, Portugal. Electronic address: diana.lima@ua.pt.
authors.forename: Diana L D
authors.initials: DLD
authors.lastname: Lima
authors.affiliation: CESAM & Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Carla Patrícia
authors.initials: CP
authors.lastname: Silva
authors.affiliation: Department of Applied Chemistry and Physics, IMARENABIO, University of León, Campus de Vegazana, 24071 León, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Otero
authors.affiliation: CESAM & Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Valdemar I
authors.initials: VI
authors.lastname: Esteves
mesh_terms: D001578:Benzopyrans / Q000494:pharmacology; D052244:Endocrine Disruptors / Q000737:chemistry / Q000494:pharmacology / Q000528:radiation effects; D004964:Estriol / Q000737:chemistry / Q000528:radiation effects*; D006207:Half-Life; D006812:Humic Substances / Q000032:analysis; D008027:Light; D010782:Photolysis; D062065:Wastewater / Q000737:chemistry; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000528:radiation effects*
chemical_list: D001578:Benzopyrans; D052244:Endocrine Disruptors; D004964:Estriol; D006812:Humic Substances; D062065:Wastewater; D014867:Water; D014874:Water Pollutants, Chemical; C005023:fulvic acid
keywords: Environmental matrices; Estriol; Fulvic acids; Humic acids; Photodegradation; XAD-4 fraction