<i>In Situ</i> Stimulation of Thiocyanate
Biodegradation through Phosphate Amendment in Gold Mine Tailings Water
Mathew
P. Watts
Han M. Gan
Lee Y. Peng
Kim-Anh Lê Cao
John W. Moreau
10.1021/acs.est.7b04152.s001
https://acs.figshare.com/articles/journal_contribution/_i_In_Situ_i_Stimulation_of_Thiocyanate_Biodegradation_through_Phosphate_Amendment_in_Gold_Mine_Tailings_Water/5580253
Thiocyanate (SCN<sup>–</sup>) is a contaminant requiring
remediation in gold mine tailings and wastewaters globally. Seepage
of SCN<sup>–</sup>-contaminated waters into aquifers can occur
from unlined or structurally compromised mine tailings storage facilities.
A wide variety of microorganisms are known to be capable of biodegrading
SCN<sup>–</sup>; however, little is known regarding the potential
of native microbes for <i>in situ</i> SCN<sup>–</sup> biodegradation, a remediation option that is less costly than engineered
approaches. Here we experimentally characterize the principal biogeochemical
barrier to SCN<sup>–</sup> biodegradation for an autotrophic
microbial consortium enriched from mine tailings, to arrive at an
environmentally realistic assessment of <i>in situ</i> SCN<sup>–</sup> biodegradation potential. Upon amendment with phosphate,
the consortium completely degraded up to ∼10 mM SCN<sup>–</sup> to ammonium and sulfate, with some evidence of nitrification of
the ammonium to nitrate. Although similarly enriched in known SCN<sup>–</sup>-degrading strains of thiobacilli, this consortium
differed in its source (mine tailings) and metabolism (autotrophy)
from those of previous studies. Our results provide a proof of concept
that phosphate limitation may be the principal barrier to <i>in situ</i> SCN<sup>–</sup> biodegradation in mine tailing
waters and also yield new insights into the microbial ecology of <i>in situ</i> SCN<sup>–</sup> bioremediation involving
autotrophic sulfur-oxidizing bacteria.
2017-10-24 00:00:00
mine tailings storage facilities
SCN
autotrophic sulfur-oxidizing bacteria
gold mine tailings
mine tailings
Gold Mine Tailings Water Thiocyanate
biodegradation