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The East Palestine, Ohio train derailment released toxic vinyl chloride (VC) and butyl acrylate (BA), which entered the watershed. Streambed sediment, surface water, and private well water samples were collected 128 and 276 days postaccident to assess the natural attenuation potential of VC and BA by quantifying biodegradation biomarker genes and conducting microcosm treatability studies. qPCR detected the aerobic VC degradation biomarkers etnC in ∼40% and etnE in ∼27% of sediments collected in both sampling campaigns in abundances reaching 10e5 gene copies g−1. The 16S rRNA genes of organohalide-respiring Dehalococcoides and Dehalogenimonas were, respectively, detected in 50 and 64% of sediment samples collected 128 days postaccident and in 63 and 88% of sediment samples collected 276 days postaccident, in abundances reaching 10e7 cells g−1. Elevated detection frequencies of VC degradation biomarker genes were measured immediately downstream of the accident site (i.e., Sulphur Run). Aerobic VC degradation occurred in all sediment microcosms and coincided with increases of etnC/etnE genes and Mycobacterium, a genus comprising aerobic VC degraders. The conversion of VC to ethene and an increased abundance of VC reductive dechlorination biomarker genes were observed in microcosms established with sediments collected from Sulphur Run. All anoxic microcosms rapidly degraded BA to innocuous products with intermediate formation of n- butanol and acrylate. The results indicate that microbiomes in the East Palestine watershed have natural attenuation capacity for VC and BA. Recommendations are made to improve first-response actions in future contaminant release accidents of this magnitude.
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234Th, 7Be, XRD data Kongsfjorden Svalbard 2020_2021
X-Ray Diffraction (XRD) analysis of streambed sediments:\n\nWe investigated the mineral composition of the particle size fraction < 63 µm (silt and clay fraction) of streambed sediments collected within the Brøggerbreen, Midtre and Austre Lovénbreen catchments by X-Ray Diffraction (XRD) analysis. The samples were collected in July 2020, dried and sieved. The measurements were performed at the University of Bremen (Germany) using a Philips X’Pert Pro diffractometer equipped with a Cu‐tube and a monochromator following the method by Vogt (2009). We evaluated the data using the QUAX full-pattern analysis software (Vogt et al., 2002) for semiquantitative determination of the major mineral composition.\n\nRadiochemical analysis of sediment cores:\n\nSediment cores were collected at 4 sites PN, IA, F, and V in Kongsfjorden, Svalbard, July 28 – 30, 2021. Gamma activities of 234Th, 7Be, 210Pb, 226Ra and 137Cs in core sections were measured in the radiochemistry lab (Prof. J.K. Cochran; Director) at the School of Marine and Atmospheric Sciences, Stony Brook University. Samples from sectioned cores were dried at 75°C. Gamma activities were measured using Canberra planar intrinsic germanium gamma detectors as follows: 234Th (63 keV) activities were counted shortly after collection and then recounted 6 months later to determine the supported activity (238U) or in some cases by using the average 234Th activity from multiple intervals at depth in the same core. 7Be (477 keV) activities were measured in the initially counted samples. Corrections were made for self-absorption of gamma radiation by samples as a function of sample mass and counting geometry (Cochran et al., 1998). It is possible that corrections for geometries may change slightly based on subsequent study so that reported activities are subject to possible updates. \n\nThese data are dicussed and cited in:\n\nLaura M. Wehrmann, Robert C. Aller, Sabine Kasten, Jack Dotzler and Grit Steinhoefel. Rapid forward and reverse weathering reactions drive cryptic silica and cation cycling in Arctic fjord sediments. Global Biogeochemical Cycles. 2025"]}
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- Award ID(s):
- 2338157
- PAR ID:
- 10651018
- Publisher / Repository:
- Zenodo
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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