Characterizing the intrinsic bioremediation potential of 1,4-dioxane and trichloroethene using innovative environmental diagnostic tools.

Characterizing the intrinsic bioremediation potential of 1,4-dioxane and trichloroethene using innovative environmental diagnostic tools.

Journal of environmental monitoring : JEM (2012-07-25)

Sheau-Yun Dora Chiang, Rebecca Mora, William H Diguiseppi, Greg Davis, Kerry Sublette, Phillip Gedalanga, Shaily Mahendra

PMID22825917

ABSTRACT

An intrinsic biodegradation study involving the design and implementation of innovative environmental diagnostic tools was conducted to evaluate whether monitored natural attenuation (MNA) could be considered as part of the remedial strategy to treat an aerobic aquifer contaminated with 1,4-dioxane and trichloroethene (TCE). In this study, advanced molecular biological and stable isotopic tools were applied to confirm in situ intrinsic biodegradation of 1,4-dioxane and TCE. Analyses of Bio-Trap® samplers and groundwater samples collected from monitoring wells verified the abundance of bacteria and enzymes capable of aerobically degrading TCE and 1,4-dioxane. Furthermore, phospholipid fatty acid analysis with stable isotope probes (PLFA-SIP) of the microbial community validated the ability for microbial degradation of TCE and 1,4-dioxane. Compound specific isotope analysis (CSIA) of groundwater samples for TCE resulted in δ(13)C values that indicated likely biodegradation of TCE in three of the four monitoring wells sampled. Results of the MNA evaluation showed that enzymes capable of aerobically degrading TCE and 1,4-dioxane were present, abundant, and active in the aquifer. Taken together, these results provide direct evidence of the occurrence of TCE and 1,4-dioxane biodegradation at the study site, supporting the selection of MNA as part of the final remedy at some point in the future.

MATERIALS

Product Number

Brand

Product Description

684228

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D), NMR tube size 10 mm × 8 in.

CRM48367

Supelco

1,4-Dioxane solution, certified reference material, 2000 μg/mL in methanol, ampule of 1 mL

704814

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 10 mM in D₂O ("100%", 99.96 atom % D), NMR tube size 5 mm × 7 in.

631833

Supelco

1,4-Dioxane solution, NMR reference standard, 5 mM in benzene-d₆ (99.6 atom % D), NMR tube size 3 mm × 8 in.

612073

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D), chromium(III) acetylacetonate 5 mg/mL, NMR tube size 3 mm × 8 in.

611905

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D), chromium(III) acetylacetonate 5 mg/mL, NMR tube size 5 mm × 8 in.

736171

Supelco

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D), NMR tube size 5 mm × 8 in.

551368

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D)

76887

Supelco

1,4-Dioxane, analytical standard

631868

Supelco

1,4-Dioxane solution, NMR reference standard, 5 mM in chloroform-d (99.8 atom % D), NMR tube size 3 mm × 8 in.

676934

Sigma-Aldrich

1,4-Dioxane, ACS reagent, ≥99.0%

360481

Sigma-Aldrich

1,4-Dioxane, ACS reagent, ≥99.0%, contains ≤25 ppm BHT as stabilizer

34857

Sigma-Aldrich

1,4-Dioxane, suitable for HPLC, ≥99.5%