title: Triclosan affects the microbial community in simulated sewage-drain-field soil and slows down xenobiotic degradation.
abstract: Effects of the common antibacterial agent triclosan on microbial communities and degradation of domestic xenobiotics were studied in simulated sewage-drain-field soil. Cultivable microbial populations decreased 22-fold in the presence of 4 mg kg⁻¹ of triclosan, and triclosan-resistant Pseudomonas strains were strongly enriched. Exposure to triclosan also changed the general metabolic profile (Ecoplate substrate profiling) and the general profile (T-RFLP) of the microbial community. Triclosan degradation was slow at all concentrations tested (0.33-81 mg kg⁻¹) during 50-days of incubation. Mineralization experiments (¹⁴C-tracers) and chemical analyses (LC-MS/MS) showed that the persistence of a linear alkylbenzene sulfonate (LAS) and a common analgesic (ibuprofen) increased with increasing triclosan concentrations (0.16-100 mg kg⁻¹). The largest effect was seen for LAS mineralization which was severely reduced by 0.16 mg kg⁻¹ of triclosan. Our findings indicate that environmentally realistic concentrations of triclosan may affect the efficiency of biodegradation in percolation systems.
authors: Department of Geochemistry, Geological Survey of Denmark and Greenland (GEUS), Copenhagen K, Denmark.
authors: Hanne
authors: H
authors: Svenningsen
authors: Trine
authors: T
authors: Henriksen
authors: Anders
authors: A
authors: Priemé
authors: Anders R
authors: AR
authors: Johnsen
mesh_terms: D000891:Anti-Infective Agents, Local / Q000633:toxicity*; D001419:Bacteria / Q000145:classification / Q000187:drug effects / Q000378:metabolism; D001673:Biodegradation, Environmental; D015169:Colony Count, Microbial; D007052:Ibuprofen / Q000032:analysis / Q000378:metabolism; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*; D014260:Triclosan / Q000633:toxicity*; D014865:Waste Disposal, Fluid; D015262:Xenobiotics / Q000032:analysis / Q000378:metabolism*
chemical_list: D000891:Anti-Infective Agents, Local; D012722:Sewage; D012989:Soil Pollutants; D015262:Xenobiotics; D014260:Triclosan; D007052:Ibuprofen