2024-03-28T18:12:07Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1576302018-09-13T08:29:55Zcom_10261_15com_10261_6col_10261_394
Bioavailability-related effects of dissolved organic matter on biodegradation of PAHs
Ortega Calvo, J. J.
Jiménez Sánchez, Celia
Posada Baquero, Rosa
García Fernández, José Luis
Cantos, Manuel
In environmental sciences, dissolved organic matter (DOM) is usually differentiated from particulate organic matter as the size fraction of organic matter smaller than 0.45 µm. This fraction typically consists of a multitude of structurally different compounds, all typically present at low concentrations, although it can differ significantly in quality (or biodegradability) and quantity in time and space. The environmental fate of organic pollutants, such as PAHs, can be affected by DOM via increased apparent solubility, desorption, transport and biodegradation. In our group, we have specifically addressed the influences of DOM quality on bioavailability-related phenomena: chemotaxis, attachment and solubilisation. We used, for our studies, different experimental models to assess the bioavailability of PAHs for biodegradation, and these included Tenax extraction, dual 14C/residue analysis of microcosm samples, dynamic passive dosing with PDMS, biphasic NAPL/water systems, and column systems. Different model DOM sources, of dissimilar quality but all with potential use in bioremediation were used, and included humic acids, root exudates, biosurfactants and organic fertilizers. We found that biodegradation of poorly bioavailable PAHs was enhanced by (bio)surfactants (Environ. Sci. Technol. 48:10869-10877, 2014), the targeted fertilization of free-oil phases or NAPLs (Environ. Sci. Technol. 45:1074-1081, 2011), by modulating the deposition and tactic motility of microbial degraders in porous media (Environ. Sci. Technol. 46:6790-6797, 2012), and by root exudates (Soil Biol. Biochem. 57:830-840, 2013; Environ. Sci. Technol. 49:4498–4505, 2015). However, a negative influence on biodegradation of PAHs by humic acids (Environ. Pollut. 184:435-442, 2014) and biosurfactants (Environ. Pollut. 205:378-384, 2015) was found if they prevented cell attachment to the PAH-loaded PDMS sources. These influences of DOM on bioavailability are relevant not only for innovation efforts in bioremediation but they have also connections with the determination of bioavailability of organic chemicals in
retrospective and prospective risk assessment and regulation (Environ. Sci. Technol. 49:10255-10264, 2015
2017-11-23T08:10:04Z
2017-11-23T08:10:04Z
2016-05-22
2017-11-23T08:10:05Z
póster de congreso
SETAC Europe 26th Annual Meeting 22-26 May 2016, Nantes, France
http://hdl.handle.net/10261/157630
eng
Sí
closedAccess
Society of Environmental Toxicology and Chemistry