title: Impacts of Pristine and Transformed Ag and Cu Engineered Nanomaterials on Surficial Sediment Microbial Communities Appear Short-Lived.
abstract: Laboratory-based studies have shown that many soluble metal and metal oxide engineered nanomaterials (ENM) exert strong toxic effects on microorganisms. However, laboratory-based studies lack the complexity of natural systems and often use "as manufactured" ENMs rather than more environmentally relevant transformed ENMs, leaving open the question of whether natural ligands and seasonal variation will mitigate ENM impacts. Because ENMs will accumulate in subaquatic sediments, we examined the effects of pristine and transformed Ag and Cu ENMs on surficial sediment microbial communities in simulated freshwater wetlands. Five identical mesocosms were dosed through the water column with either Ag(0), Ag2S, CuO or CuS ENMs (nominal sizes of 4.67 ± 1.4, 18.1 ± 3.2, 31.1 ± 12, and 12.4 ± 4.1, respectively) or Cu(2+). Microbial communities were examined at 0, 7, 30, 90, 180, and 300 d using qPCR and high-throughput 16S rRNA gene sequencing. Results suggest differential short-term impacts of Ag(0) and Ag2S, similarities between CuO and CuS, and differences between Cu ENMs and Cu(2+). PICRUSt-predicted metagenomes displayed differential effects of Ag treatments on photosynthesis and of Cu treatments on methane metabolism. By 300 d, all metrics pointed to reconvergence of ENM-dosed mesocosm microbial community structure and composition, suggesting that the long-term microbial community impacts from a pulse of Ag or Cu ENMs are limited.
authors: Civil and Environmental Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.|Center for the Environmental Implications of NanoTechnology (CEINT) , Durham, North Carolina 27708, United States.
authors: Joe D
authors: JD
authors: Moore
authors: Civil and Environmental Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.|Center for the Environmental Implications of NanoTechnology (CEINT) , Durham, North Carolina 27708, United States.
authors: John P
authors: JP
authors: Stegemeier
authors: Civil and Environmental Engineering, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States.|Computational and Systems Biology, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States.
authors: Kyle
authors: K
authors: Bibby
authors: Center for the Environmental Implications of NanoTechnology (CEINT) , Durham, North Carolina 27708, United States.
authors: Stella M
authors: SM
authors: Marinakos
authors: Civil and Environmental Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.|Center for the Environmental Implications of NanoTechnology (CEINT) , Durham, North Carolina 27708, United States.
authors: Gregory V
authors: GV
authors: Lowry
authors: Civil and Environmental Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.|Center for the Environmental Implications of NanoTechnology (CEINT) , Durham, North Carolina 27708, United States.
authors: Kelvin B
authors: KB
authors: Gregory
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D044822:Biodiversity; D001711:Biotransformation; D003300:Copper / Q000737:chemistry*; D000067493:Dynamic Light Scattering; D019015:Geologic Sediments / Q000382:microbiology*; D054892:Metagenome; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010788:Photosynthesis / Q000235:genetics; D016062:Porosity; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012834:Silver / Q000737:chemistry*; D055672:Static Electricity; D014867:Water
chemical_list: D012336:RNA, Ribosomal, 16S; D014867:Water; D012834:Silver; D003300:Copper