title: Soil microbial response to photo-degraded C60 fullerenes.
abstract: Recent studies indicate that while unfunctionalized carbon nanomaterials (CNMs) exhibit very low decomposition rates in soils, even minor surface functionalization (e.g., as a result of photochemical weathering) may accelerate microbial decay. We present results from a C60 fullerene-soil incubation study designed to investigate the potential links between photochemical and microbial degradation of photo-irradiated C60. Irradiating aqueous (13)C-labeled C60 with solar-wavelength light resulted in a complex mixture of intermediate products with decreased aromaticity. Although addition of irradiated C60 to soil microcosms had little effect on net soil respiration, excess (13)C in the respired CO2 demonstrates that photo-irradiating C60 enhanced its degradation in soil, with ∼ 0.78% of 60 day photo-irradiated C60 mineralized. Community analysis by DGGE found that soil microbial community structure was altered and depended on the photo-treatment duration. These findings demonstrate how abiotic and biotic transformation processes can couple to influence degradation of CNMs in the natural environment.
authors.affiliation: Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette 47907, IN, USA.
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Berry
authors.affiliation: Department of Agronomy, Purdue University, West Lafayette 47907, IN, USA.
authors.forename: Andrea P
authors.initials: AP
authors.lastname: Clavijo
authors.affiliation: Lyles School of Civil Engineering and Division of Environmental and Ecological Engineering, Purdue University, West Lafayette 47907, IN, USA.
authors.forename: Yingcan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Lyles School of Civil Engineering and Division of Environmental and Ecological Engineering, Purdue University, West Lafayette 47907, IN, USA.
authors.forename: Chad T
authors.initials: CT
authors.lastname: Jafvert
authors.affiliation: Department of Agronomy, Purdue University, West Lafayette 47907, IN, USA.
authors.forename: Ronald F
authors.initials: RF
authors.lastname: Turco
authors.affiliation: Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette 47907, IN, USA. Electronic address: filley@purdue.edu.
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Filley
mesh_terms: D002244:Carbon; D004777:Environment; D037741:Fullerenes / Q000633:toxicity*; D049329:Nanostructures; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism / Q000633:toxicity*; D014867:Water
chemical_list: D037741:Fullerenes; D012987:Soil; D012989:Soil Pollutants; D014867:Water; D002244:Carbon; C069837:fullerene C60
keywords: Carbon nanomaterials; Emerging pollutants; Fullerenes; Microbial degradation; Photo decay; Soil