TY - JOUR
T1 - An evaluation of the impact of multiwalled carbon nanotubes on soil microbial community structure and functioning
AU - Shrestha, Babina
AU - Acosta-Martinez, Veronica
AU - Cox, Stephen B.
AU - Green, Micah J.
AU - Li, Shibin
AU - Cañas-Carrell, Jaclyn E.
PY - 2013/10/15
Y1 - 2013/10/15
N2 - This study evaluated the impacts of multiwalled carbon nanotubes (MWNTs) on microbial community composition and functioning in a sandy loam soil over 90. d. We used test concentrations in the range of lower MWNT concentrations (10. mg/kg) to extremely high MWNT concentrations (10,000. mg/kg) as a worst case scenario. We observed no effects of MWNTs on soil respiration, enzymatic activities, and microbial community composition at 10, 100 and 1000. mg/kg. However, increases in fungal fatty acid methyl ester markers were observed at the highest treatment. In addition, pyrosequencing demonstrated a decreased abundance of some bacterial genera like Derxia, Holophaga, Opitutus and Waddlia at the highest treatment while bacterial genera that are considered potential degraders of recalcitrant contaminants (such as polycyclic aromatic hydrocarbons) like Rhodococcus, Cellulomonas, Nocardioides and Pseudomonas increased. These results suggest a shift in soil microbial community composition to more tolerant microbial populations in the presence of extremely high MWNT concentrations. It is unlikely that the change observed at 10,000. mg/kg is due to metal or carbon impurities as the MWNTs used in this study were of high purity. Given the need for wide-ranging data for regulation and risk assessment of nanomaterials, this study provides valuable data.
AB - This study evaluated the impacts of multiwalled carbon nanotubes (MWNTs) on microbial community composition and functioning in a sandy loam soil over 90. d. We used test concentrations in the range of lower MWNT concentrations (10. mg/kg) to extremely high MWNT concentrations (10,000. mg/kg) as a worst case scenario. We observed no effects of MWNTs on soil respiration, enzymatic activities, and microbial community composition at 10, 100 and 1000. mg/kg. However, increases in fungal fatty acid methyl ester markers were observed at the highest treatment. In addition, pyrosequencing demonstrated a decreased abundance of some bacterial genera like Derxia, Holophaga, Opitutus and Waddlia at the highest treatment while bacterial genera that are considered potential degraders of recalcitrant contaminants (such as polycyclic aromatic hydrocarbons) like Rhodococcus, Cellulomonas, Nocardioides and Pseudomonas increased. These results suggest a shift in soil microbial community composition to more tolerant microbial populations in the presence of extremely high MWNT concentrations. It is unlikely that the change observed at 10,000. mg/kg is due to metal or carbon impurities as the MWNTs used in this study were of high purity. Given the need for wide-ranging data for regulation and risk assessment of nanomaterials, this study provides valuable data.
KW - MWNTs
KW - Nanomaterials
KW - Pyrosequencing
KW - Risk assessment
KW - Soil microbial community
UR - http://www.scopus.com/inward/record.url?scp=84881252003&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2013.07.031
DO - 10.1016/j.jhazmat.2013.07.031
M3 - Article
C2 - 23921182
AN - SCOPUS:84881252003
SN - 0304-3894
VL - 261
SP - 188
EP - 197
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
ER -