Spelling suggestions: "subject:"tonalite"" "subject:"tonalidade""
1 |
Presence, Bioconcentration and Fate of Galaxolide and Tonalide Fragrances in the North Saskatchewan River, EdmontonLefebvre, Claudine January 2016 (has links)
Synthetic musks are incorporated extensively in personal care products to improve their scent, increase their fragrance stability, and prolong their shelf-life. As a consequence, these persistent musks are being released at a considerable rate by wastewater treatment plants and are frequently detected in surface water, bottom sediment, air, and aquatic biota near urban areas. In addition to their hydrophobicity, two synthetic musks, Galaxolide (HHCB) and Tonalide (AHTN), were reported to cause endocrine disruption in fish species. Although most of the toxic effects in past studies were observed at high doses, HHCB and AHTN were shown to bioaccumulate very differently depending on the aquatic species tested. As bioaccumulation and fate of contaminants are important considerations when regulating persistent chemicals, an improved understanding of the bioaccumulation potential of these chemicals is needed. In this thesis, an assessment of the presence, bioconcentration and fate of HHCB and AHTH was provided in an area exposed to the effluent of the Gold Bar wastewater treatment plant in the North Saskatchewan River (Edmonton). HHCB and AHTN were quantified in fathead minnows (Pimephales promelas) exposed downstream of the effluent, with an adapted method for analysis of musks in fish, using PAHs as recovery standards. Method development and recoveries are summarized. Highest bioconcentration factors were 24,500 and 22,300 for HHCB and AHTN respectively, and were observed 1 km downstream of the outfall. Musks were found in most fathead minnows exposed at reference sites upstream as well as at the furthest site, 9.9 km from the outfall. Musk concentrations in water at these sites were used in the assessment of the fate of HHCB and AHTN by fugacity modeling with QWASI software. In order to assess fate, a contaminated portion of the North Saskatchewan River was divided in a series of compartments that were each treated as connected individual water bodies. HHCB and AHTN losses were mostly due to water advection and sedimentation fluxes. Model fit was assessed by comparing predicted to measured data.
|
Page generated in 0.0478 seconds