title: Nanomaterials in Biosolids Inhibit Nodulation, Shift Microbial Community Composition, and Result in Increased Metal Uptake Relative to Bulk/Dissolved Metals.
abstract: We examined the effects of amending soil with biosolids produced from a pilot-scale wastewater treatment plant containing a mixture of metal-based engineered nanomaterials (ENMs) on the growth of Medicago truncatula, its symbiosis with Sinorhizobium meliloti, and on soil microbial community structure. Treatments consisted of soils amended with biosolids generated with (1) Ag, ZnO, and TiO2 ENMs introduced into the influent wastewater (ENM biosolids), (2) AgNO3, Zn(SO4)2, and micron-sized TiO2 (dissolved/bulk metal biosolids) introduced into the influent wastewater stream, or (3) no metal added to influent wastewater (control). Soils were amended with biosolids to simulate 20 years of metal loading, which resulted in nominal metal concentrations of 1450, 100, and 2400 mg kg(-1) of Zn, Ag, and Ti, respectively, in the dissolved/bulk and ENM treatments. Tissue Zn concentrations were significantly higher in the plants grown in the ENM treatment (182 mg kg(-1)) compared to those from the bulk treatment (103 mg kg(-1)). Large reductions in nodulation frequency, plant growth, and significant shifts in soil microbial community composition were found for the ENM treatment compared to the bulk/dissolved metal treatment. These results suggest differences in metal bioavailability and toxicity between ENMs and bulk/dissolved metals at concentrations relevant to regulatory limits.
authors.affiliation: †Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546, United States.|‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.|§Center for Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, North Carolina 27708, United States.|∥CSIRO Land and Water, Waite Campus, Urrbrae, South Australia 5064, Australia.
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Judy
authors.affiliation: †Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546, United States.|‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.
authors.forename: David H
authors.initials: DH
authors.lastname: McNear
authors.affiliation: †Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546, United States.|‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.|§Center for Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, North Carolina 27708, United States.
authors.forename: Chun
authors.initials: C
authors.lastname: Chen
authors.affiliation: †Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546, United States.|‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.
authors.forename: Ricky W
authors.initials: RW
authors.lastname: Lewis
authors.affiliation: †Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546, United States.|‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.|§Center for Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, North Carolina 27708, United States.
authors.forename: Olga V
authors.initials: OV
authors.lastname: Tsyusko
authors.affiliation: †Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546, United States.|‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.|§Center for Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, North Carolina 27708, United States.|⊥CSIRO Land and Water, 41 Boggo Road, Ecosciences Precinct, Dutton Park Queensland, 4102, Australia.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Bertsch
authors.affiliation: †Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546, United States.
authors.forename: William
authors.initials: W
authors.lastname: Rao
authors.affiliation: ‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.|§Center for Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, North Carolina 27708, United States.
authors.forename: John
authors.initials: J
authors.lastname: Stegemeier
authors.affiliation: ‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.|§Center for Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, North Carolina 27708, United States.
authors.forename: Gregory V
authors.initials: GV
authors.lastname: Lowry
authors.affiliation: ‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.|∇Department of Sustainable Soils and Grassland Systems, Rothamsted Research, West Common, Harpenden Hertfordshire, AL5 2JQ, United Kingdom.
authors.forename: Steve P
authors.initials: SP
authors.lastname: McGrath
authors.affiliation: ‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.|∇Department of Sustainable Soils and Grassland Systems, Rothamsted Research, West Common, Harpenden Hertfordshire, AL5 2JQ, United Kingdom.
authors.forename: Mark
authors.initials: M
authors.lastname: Durenkamp
authors.affiliation: †Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546, United States.|‡Transatlantic Initiative for Nanotechnology and the Environment (TINE), University of Kentucky, Lexington, Kentucky 40546, United States.|§Center for Environmental Implications of Nanotechnology (CEINT), Duke University, Durham, North Carolina 27708, United States.
authors.forename: Jason M
authors.initials: JM
authors.lastname: Unrine
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000254:growth & development*; D018533:Biomass; D046913:Medicago truncatula / Q000187:drug effects / Q000502:physiology; D008670:Metals / Q000378:metabolism*; D049329:Nanostructures / Q000633:toxicity*; D055170:Plant Root Nodulation / Q000187:drug effects*; D018520:Plant Shoots / Q000033:anatomy & histology; D012722:Sewage / Q000737:chemistry*; D012988:Soil Microbiology
chemical_list: D008670:Metals; D012722:Sewage