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Aamir Khan M, Sharma A, Yadav S, Celin SM, Sharma S. A sketch of microbiological remediation of explosives-contaminated soil focused on state of art and the impact of technological advancement on hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) degradation. CHEMOSPHERE 2022; 294:133641. [PMID: 35077733 DOI: 10.1016/j.chemosphere.2022.133641] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 01/02/2022] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
When high-energy explosives such as hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), 2,4,6-trinitrotoluene (TNT) are discharged into the surrounding soil and water during production, testing, open dumping, military, or civil activities, they leave a toxic footprint. The US Environmental Protection Agency has labeled RDX as a potential human carcinogen that must be degraded from contaminated sites quickly. Bioremediation of RDX is an exciting prospect that has received much attention in recent years. However, a lack of understanding of RDX biodegradation and the limitations of current approaches have hampered the widespread use of biodegradation-based strategies for RDX remediation at contamination sites. Consequently, new bioremediation technologies are required to enhance performance. In this review, we explore the requirements for in-silico analysis for producing biological models of microbial remediation of RDX in soil. On the other hand, potential gene editing methods for getting the host with target gene sequences responsible for the breakdown of RDX are also reported. Microbial formulations and biosensors for detection and bioremediation are also briefly described. The biodegradation of RDX offers an alternative remediation method that is both cost-effective and ecologically acceptable. It has the potential to be used in conjunction with other cutting-edge technologies to further increase the efficiency of RDX degradation.
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Affiliation(s)
- Mohd Aamir Khan
- Centre for Rural Development & Technology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
| | - Abhishek Sharma
- Amity Food and Agriculture Foundation, Amity University Uttar Pradesh, Noida, 201313, India.
| | - Sonal Yadav
- Centre for Rural Development & Technology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
| | - S Mary Celin
- Centre for Fire, Explosives and Environment Safety, Defence Research & Development Organization, Brig. Mazumdar Road, Delhi, 110 054, India
| | - Satyawati Sharma
- Centre for Rural Development & Technology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
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Zhao W, Yang X, Feng A, Yan X, Wang L, Liang T, Liu J, Ma H, Zhou Y. Distribution and migration characteristics of dinitrotoluene sulfonates (DNTs) in typical TNT production sites: Effects and health risk assessment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 287:112342. [PMID: 33740743 DOI: 10.1016/j.jenvman.2021.112342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/02/2021] [Accepted: 03/07/2021] [Indexed: 06/12/2023]
Abstract
The production of 2,4,6-trinitrotoluene (TNT) produces a great deal of waste water, and dinitrotoluene sulfonates (DNTs) are the main pollutants in its waste. This paper presents a pilot investigation on the geochemical transformation of DNTs affected by historical wastewater spillage from a typical TNT production company in Northwest China. In the horizontal direction, DNTs diffused from the evaporation pond to the surrounding area of the site, and the concentration of DNTs in the evaporation pond surface soil exceeded 1000 mg/kg. The horizontal distribution of DNTs in the site showed a migration trend to the east and south of evaporation, which was consistent with the terrain of high northwest and low southeast of the site. Due to the high water solubility of pollutants, water flow is the main driving force for the horizontal distribution of DNTs. In the vertical direction, the concentration of pollutants gradually increased with the depth of the soil. DNTs are mainly adsorbed in the third layer (6.0-8.0 m). It can be seen that the accumulation of the 2,4-DNTs-3-SO3- is obviously larger than that of the 2,4-DNTs-5-SO3-, which may be related to the steric hindrance effect of sulfonic acid groups in the two isomers. Results showed DNTs distribution strongly linked to soil physicochemical properties and the migration of DNTs in soil exhibited obvious heterogeneity in time and space. The carcinogenic risks in surface soil (0-1.5 m) and lower soil (1.5-6.0 m, 6.0-8.0 m) are all higher than 1✕10-6; non-carcinogenic risk surface soil (0-1.5 m) is 4.011✕10, which is greater than 1, indicating that they may cause certain harm to the human body. Meanwhile, this study presented a pioneering investigation for the contamination and geochemical transfer of DNTs.
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Affiliation(s)
- Wenchu Zhao
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Xiao Yang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100190, China.
| | - Aixi Feng
- Yuhuan Environmental Technology Co., Ltd, Shijiazhuang, 050000, China
| | - Xiulan Yan
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100190, China.
| | - Lingqing Wang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Tao Liang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Juan Liu
- Institute of Environmental Research at Greater Bay, Key Laboratory of Water Quality and Conservation in the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, China
| | - Huansong Ma
- Yuhuan Environmental Technology Co., Ltd, Shijiazhuang, 050000, China
| | - Yaoyu Zhou
- College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China
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Zhou B, Wu Y, Chan J, Wang S, Hu S. Batch Adsorption and Column Transport Studies of 2,4,6-Trinitrotoluene in Chinese Loess. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2019; 103:75-81. [PMID: 30840086 DOI: 10.1007/s00128-019-02578-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 02/21/2019] [Indexed: 06/09/2023]
Abstract
In present study, batch and column tests were conducted to investigate the kinetic and thermodynamic characteristics of the adsorption and transport of 2,4,6-trinitrotoluene (TNT) in Chinese loess with specific focus on the role of inherent colloid particles. Batch tests showed that a lot of TNT was absorbed in suspended colloid particles, and its adsorption reached equilibrium after about 10 h, the adsorption process can be best-fit by the pseudo-second order kinetic and Freundlich model. The adsorption was spontaneous, endothermic process, implying the adsorbed TNT is likely to release from soil matrix. These portend that the adsorbed TNT has a potential to co-transport with inherent colloid particles in loess. The column tests identified the potential, and showed TNT transport had obvious retardation effect, which may be ascribed to the release and transport of inherent colloidal particles as a key carrier. These findings are helpful to evaluate the loess interception and antifouling performance.
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Affiliation(s)
- Bo Zhou
- Department of Applied Chemistry, Northwestern Polytechnical University, Xi'an, 710072, China
| | - Yaoguo Wu
- Department of Applied Chemistry, Northwestern Polytechnical University, Xi'an, 710072, China.
| | - Jiangwei Chan
- Department of Applied Chemistry, Northwestern Polytechnical University, Xi'an, 710072, China
| | - Sichang Wang
- Department of Applied Chemistry, Northwestern Polytechnical University, Xi'an, 710072, China
| | - Sihai Hu
- Department of Applied Chemistry, Northwestern Polytechnical University, Xi'an, 710072, China
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Yu HA, Nic Daeid N, Dawson LA, DeTata DA, Lewis SW. Explosive detonation causes an increase in soil porosity leading to increased TNT transformation. PLoS One 2017; 12:e0189177. [PMID: 29281650 PMCID: PMC5744939 DOI: 10.1371/journal.pone.0189177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Accepted: 11/17/2017] [Indexed: 11/18/2022] Open
Abstract
Explosives are a common soil contaminant at a range of sites, including explosives manufacturing plants and areas associated with landmine detonations. As many explosives are toxic and may cause adverse environmental effects, a large body of research has targeted the remediation of explosives residues in soil. Studies in this area have largely involved spiking 'pristine' soils using explosives solutions. Here we investigate the fate of explosives present in soils following an actual detonation process and compare this to the fate of explosives spiked into 'pristine' undetonated soils. We also assess the effects of the detonations on the physical properties of the soils. Our scanning electron microscopy analyses reveal that detonations result in newly-fractured planes within the soil aggregates, and novel micro Computed Tomography analyses of the soils reveal, for the first time, the effect of the detonations on the internal architecture of the soils. We demonstrate that detonations cause an increase in soil porosity, and this correlates to an increased rate of TNT transformation and loss within the detonated soils, compared to spiked pristine soils. We propose that this increased TNT transformation is due to an increased bioavailability of the TNT within the now more porous post-detonation soils, making the TNT more easily accessible by soil-borne bacteria for potential biodegradation. This new discovery potentially exposes novel remediation methods for explosive contaminated soils where actual detonation of the soil significantly promotes subsequent TNT degradation. This work also suggests previously unexplored ramifications associated with high energy soil disruption.
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Affiliation(s)
- Holly A. Yu
- Department of Chemistry, Curtin University, Perth, WA, Australia
- Curtin Institute of Functional Molecules and Interfaces, Curtin University, Perth, WA, Australia
- Centre for Anatomy and Human Identification, School of Science and Engineering, University of Dundee, Dundee, United Kingdom
| | - Niamh Nic Daeid
- Centre for Anatomy and Human Identification, School of Science and Engineering, University of Dundee, Dundee, United Kingdom
| | - Lorna A. Dawson
- The James Hutton Institute, Aberdeen, Scotland, United Kingdom
| | - David A. DeTata
- Forensic Science Laboratory, ChemCentre, Perth, WA, Australia
| | - Simon W. Lewis
- Department of Chemistry, Curtin University, Perth, WA, Australia
- Curtin Institute of Functional Molecules and Interfaces, Curtin University, Perth, WA, Australia
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Coyle CG, Waisner SA, Medina VF, Griggs CS. Use of dilute ammonia gas for treatment of 1,2,3-trichloropropane and explosives-contaminated soils. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 204:775-782. [PMID: 28416262 DOI: 10.1016/j.jenvman.2017.03.098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 03/21/2017] [Accepted: 03/31/2017] [Indexed: 06/07/2023]
Abstract
Laboratory studies were performed to test a novel reactive gas process for in-situ treatment of soils containing halogenated propanes or explosives. A soil column study, using a 5% ammonia-in-air mixture, established that the treatment process can increase soil pH from 7.5 to 10.2. Batch reactor experiments were performed to demonstrate contaminant destruction in sealed jars exposed to ammonia. Comparison of results from batch reactors that were, and were not, exposed to ammonia demonstrated reductions in concentrations of 1,2,3-trichloropropane (TCP), 1,3-dichloropropane (1,3-DCP), 1,2-dicholoropropane (1,2-DCP) and dibromochloropropane (DBCP) that ranged from 34 to 94%. Decreases in TCP concentrations at 23° C ranged from 37 to 65%, versus 89-94% at 62° C. A spiked soil column study was also performed using the same set of contaminants. The study showed a pH penetration distance of 30 cm in a 2.5 cm diameter soil column (with a pH increase from 8 to > 10), due to treatment via 5% ammonia gas at 1 standard cubic centimeter per minute (sccm) for 7 days. Batch reactor tests using explosives contaminated soils exhibited a 97% decrease in 2,4,6-trinitrotoluene (TNT), an 83% decrease in nitrobenzene, and a 6% decrease in hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). A biotransformation study was also performed to investigate whether growth of ammonia-oxidizing microorganisms could be stimulated via prolonged exposure of soil to ammonia. Over the course of the 283 day study, only a very small amount of nitrite generation was observed; indicating very limited ammonia monooxygenase activity. Overall, the data indicate that ammonia gas addition can be a viable approach for treating halogenated propanes and some types of explosives in soils.
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Key Words
- 1,2,3,-Trichloropropane
- 2,4,6,-Trinitrotoluene
- Alkaline hydrolysis
- Ammonia
- Hexahydro-1,3,5-trinitro-1,3,5-triazine
- Treatment
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Affiliation(s)
- Charles G Coyle
- U.S. Army Corps of Engineers, Huntsville Engineering and Support Center Environmental & Munitions CX, 1616 Capitol Ave, Suite 9200, Omaha, NE, 68102-9200, USA.
| | - Scott A Waisner
- Engineer Research & Development Center, CEERD-EP-E, 3909 Halls Ferry Rd., Vicksburg, MS, 39180, USA
| | - Victor F Medina
- Engineer Research & Development Center, CEERD-EP-E, 3909 Halls Ferry Rd., Vicksburg, MS, 39180, USA
| | - Chris S Griggs
- Engineer Research & Development Center, CEERD-EP-E, 3909 Halls Ferry Rd., Vicksburg, MS, 39180, USA
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Kuo DTF, Simini M, Allen HE. Leaching of propellant compounds from munition residues may be controlled by sorption to nitrocellulose. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 599-600:2135-2141. [PMID: 28558434 DOI: 10.1016/j.scitotenv.2017.05.155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 05/17/2017] [Accepted: 05/17/2017] [Indexed: 06/07/2023]
Abstract
Sustainable management of military ranges requires effective assessment of surface mobility and leaching potential of propellant compounds (PCs). Previous studies have focused mostly on PCs' dissolution from fired residues and their sorption to soil components. This work investigated the potential role of nitrocellulose, a major component in propellants, in the binding of PCs to propellant residues. Sorption isotherms of military grade nitrocellulose for dissolved nitroglycerine (NG) or 2,4-dinitrotoluene (2,4-DNT) was measured in batch experiments and were determined to be SNG=102.39(±0.05)CNG0.916(±0.032) and S2,4-DNT=103.08(±0.01)C2,4-DNT0.668(±0.010) (S and C in mg/kgnitrocellulose and mg/Lwat, respectively). Solid-to-water partitioning for NG and 2,4-DNT was 100 times greater in propellant residues than in typical military ranges soils. Since nitrocellulose can sorb NG and 2,4-DNT up to 23 and 5% of its mass, respectively, it can slow down, through retarded diffusion, the leaching of PCs from fired residues over the typical composition ranges of common propellants. The slow leaching of PCs from propellant grains in column studies can be better interpreted by considering their sorptive interaction with nitrocellulose in addition to dissolution kinetics. With nitrocellulose as the carrying matrix, residue-bound PCs may migrate farther and persist longer in subsurface environment.
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Affiliation(s)
- Dave T F Kuo
- Department of Architecture and Civil Engineering, City University of Hong Kong, Kowloon City, Hong Kong; City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China.
| | - Michael Simini
- US Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, MD 21014, USA
| | - Herbert E Allen
- Department of Civil and Environmental Engineering, University of Delaware, Newark, DE 19716, USA
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Torralba Sanchez TL, Liang Y, Di Toro DM. Estimating Grass-Soil Bioconcentration of Munitions Compounds from Molecular Structure. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:11205-11214. [PMID: 28816038 DOI: 10.1021/acs.est.7b02572] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A partitioning-based model is presented to estimate the bioconcentration of five munitions compounds and two munition-like compounds in grasses. The model uses polyparameter linear free energy relationships (pp-LFERs) to estimate the partition coefficients between soil organic carbon and interstitial water and between interstitial water and the plant cuticle, a lipid-like plant component. Inputs for the pp-LFERs are a set of numerical descriptors computed from molecular structure only that characterize the molecular properties that determine the interaction with soil organic carbon, interstitial water, and plant cuticle. The model is validated by predicting concentrations measured in the whole plant during independent uptake experiments with a root-mean-square error (log predicted plant concentration-log observed plant concentration) of 0.429. This highlights the dominant role of partitioning between the exposure medium and the plant cuticle in the bioconcentration of these compounds. The pp-LFERs can be used to assess the environmental risk of munitions compounds and munition-like compounds using only their molecular structure as input.
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Affiliation(s)
- Tifany L Torralba Sanchez
- Department of Civil & Environmental Engineering, University of Delaware , Newark, Delaware 19716, United States
| | - Yuzhen Liang
- Department of Civil & Environmental Engineering, University of Delaware , Newark, Delaware 19716, United States
| | - Dominic M Di Toro
- Department of Civil & Environmental Engineering, University of Delaware , Newark, Delaware 19716, United States
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Heerspink BP, Pandey S, Boukhalfa H, Ware DS, Marina O, Perkins G, Vesselinov VV, WoldeGabriel G. Fate and transport of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and its degradation products in sedimentary and volcanic rocks, Los Alamos, New Mexico. CHEMOSPHERE 2017; 182:276-283. [PMID: 28500972 DOI: 10.1016/j.chemosphere.2017.04.149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 04/26/2017] [Accepted: 04/30/2017] [Indexed: 06/07/2023]
Abstract
High-explosive compounds including hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) were used extensively in weapons research and testing at Los Alamos National Laboratory (LANL). Liquid effluents containing RDX were released to an outfall pond that flowed to Cañon de Valle at LANL's Technical Area 16 (TA-16), resulting in the contamination of the alluvial, intermediate and regional groundwater bodies. Monitoring of groundwater within Cañon de Valle has shown persistent RDX in the intermediate perched zone located between 225 and 311 m below ground surface. Monitoring data also show detectable levels of RDX putative anaerobic degradation products. Batch and column experiments were conducted to determine the extent of adsorption-desorption and transport of RDX and its degradation products (MNX, DNX, and TNX) in major rock types that are within the RDX plume. All experiments were performed in the dark using water obtained from a well located at the center of the plume, which is fairly oxic and has a neutral pH of 7.5. Retardation factors and partitioning coefficient (Kd) values for RDX were calculated from batch experiments. Additionally, retardation factors and Kd values for RDX and its degradation products were calibrated from column experiments using a one-dimensional transport model with equilibrium sorption (linear isotherm). Results from the column and batch experiments showed little to no sorption of RDX to the aquifer materials tested, with retardation factors ranging from 1.0 to 1.8 and Kd values varying from 0 to 0.70 L/kg. Results also showed no measurable differences between the transport properties of RDX and its degradation products.
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Affiliation(s)
- Brent Porter Heerspink
- Earth Systems Observations (EES-14), Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Sachin Pandey
- Computational Earth Science (EES-16), Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Hakim Boukhalfa
- Earth Systems Observations (EES-14), Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Doug S Ware
- Earth Systems Observations (EES-14), Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Oana Marina
- Earth Systems Observations (EES-14), Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - George Perkins
- Earth Systems Observations (EES-14), Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Velimir V Vesselinov
- Computational Earth Science (EES-16), Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Giday WoldeGabriel
- Earth Systems Observations (EES-14), Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
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Yu H, DeTata D, Lewis S, Nic Daeid N. The stability of TNT, RDX and PETN in simulated post-explosion soils: Implications of sample preparation for analysis. Talanta 2017; 164:716-726. [DOI: 10.1016/j.talanta.2016.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 06/30/2016] [Accepted: 07/01/2016] [Indexed: 10/21/2022]
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11
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Smith RW, Tobias C, Vlahos P, Cooper C, Ballentine M, Ariyarathna T, Fallis S, Groshens TJ. Mineralization of RDX-derived nitrogen to N2 via denitrification in coastal marine sediments. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:2180-7. [PMID: 25594316 DOI: 10.1021/es505074v] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a common constituent of military explosives. Despite RDX contamination at numerous U.S. military facilities and its mobility to aquatic systems, the fate of RDX in marine systems remains largely unknown. Here, we provide RDX mineralization pathways and rates in seawater and sediments, highlighting for the first time the importance of the denitrification pathway in determining the fate of RDX-derived N. (15)N nitro group labeled RDX ((15)N-[RDX], 50 atom %) was spiked into a mesocosm simulating shallow marine conditions of coastal Long Island Sound, and the (15)N enrichment of N2 (δ(15)N2) was monitored via gas bench isotope ratio mass spectrometry (GB-IRMS) for 21 days. The (15)N tracer data were used to model RDX mineralization within the context of the broader coastal marine N cycle using a multicompartment time-stepping model. Estimates of RDX mineralization rates based on the production and gas transfer of (15)N2O and (15)N2 ranged from 0.8 to 10.3 μmol d(-1). After 22 days, 11% of the added RDX had undergone mineralization, and 29% of the total removed RDX-N was identified as N2. These results demonstrate the important consideration of sediment microbial communities in management strategies addressing cleanup of contaminated coastal sites by military explosives.
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Affiliation(s)
- Richard W Smith
- University of Connecticut , Department of Marine Sciences 1080 Shennocossett Road, Groton, Connecticut 06340, United States
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12
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Alnemrat S, Hooper JP. Predicting Solubility of Military, Homemade, and Green Explosives in Pure and Saline Water using COSMO-RS. PROPELLANTS EXPLOSIVES PYROTECHNICS 2013. [DOI: 10.1002/prep.201300071] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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13
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Payne ZM, Lamichhane KM, Babcock RW, Turnbull SJ. Pilot-scale in situ bioremediation of HMX and RDX in soil pore water in Hawaii. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2013; 15:2023-2029. [PMID: 24061783 DOI: 10.1039/c3em00320e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A nine-month in situ bioremediation study was conducted in Makua Military Reservation (MMR) in Oahu, Hawaii (USA) to evaluate the potential of molasses to enhance biodegradation of royal demolition explosive (RDX) and high-melting explosive (HMX) contaminated soil below the root zone. MMR has been in operation since the 1940's resulting in subsurface contamination that in some locations exceeds USEPA preliminary remediation goals for these chemicals. A molasses-water mixture (1 : 40 dilution) was applied to a treatment plot and clean water was applied to a control plot via seven flood irrigation events. Pore water samples were collected from 12 lysimeters installed at different depths in 3 boreholes in each test plot. The difference in mean concentrations of RDX in pore water samples from the two test plots was very highly significant (p < 0.001). The concentrations differences with depth were also very highly significant (p < 0.001) and degradation was greatly enhanced at depths from 5 to 13.5 ft. biodegradation was modeled as first order and the rate constant was 0.063 per day at 5 ft and decreased to 0.023 per day at 11 ft to 13.5 ft depth. Enhanced biodegradation of HMX was also observed in molasses treated plot samples but only at a depth of 5 ft. The difference in mean TOC concentration (surrogate for molasses) was highly significant with depth (p = 0.003) and very highly significant with treatment (p < 0.001). Mean total nitrogen concentrations also differed significantly with treatment (p < 0.001) and depth (p = 0.059). The molasses water mixture had a similar infiltration rate to that of plain water (average 4.12 ft per day) and reached the deepest sensor (31 ft) within 5 days of application. Most of the molasses was consumed by soil microorganisms by about 13.5 feet below ground surface and treatment of deeper depths may require greater molasses concentrations and/or more frequent flood irrigation. Use of the bioremediation method described herein could allow the sustainable use of live fire training ranges by enhancing biodegradation of explosives in situ and preventing them from migrating to through the vadose zone to underlying ground water and off-site.
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Affiliation(s)
- Zachary M Payne
- Environet, Inc., 1286 Queen Emma Street, Honolulu, Hawaii 96813, USA.
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Sharma P, Mayes MA, Tang G. Role of soil organic carbon and colloids in sorption and transport of TNT, RDX and HMX in training range soils. CHEMOSPHERE 2013; 92:993-1000. [PMID: 23602657 DOI: 10.1016/j.chemosphere.2013.03.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 01/29/2013] [Accepted: 03/20/2013] [Indexed: 06/02/2023]
Abstract
Contamination of soils and groundwater by munitions compounds (MCs) is of significant concern at many U.S. Department of Defense sites. Soils were collected from operational training ranges in Maryland (APG), Massachusetts (MMR-B and MMR-E) and Washington (JBLM) and sorption and transport studies were conducted to investigate the effects of soil organic carbon (OC) and textural clay content on fate of dissolved MCs (TNT, RDX, HMX). Sorption experiments showed higher distribution coefficients [TNT:42-68 L kg(-1), RDX:6.9-8.7 L kg(-1) and HMX:2.6-3.1 L kg(-1)] in OC rich soils (JBLM, MMR-E) compared to clay rich soils (MMR-B and APG) [TNT:19-21 L kg(-1), RDX:2.5-3.4 L kg(-1), HMX:0.9-1.2 L kg(-1)]. In column experiments, breakthrough of MCs was faster in MMR-B and APG compared to MMR-E and JBLM soils. Among TNT, RDX and HMX, breakthrough was fastest for RDX followed by HMX and TNT for all columns. Defining the colloidal fraction as the difference between unfiltered samples and samples filtered with a 3 kDa filter, ~36%, ~15% and ~9% of TNT, RDX and HMX were found in the colloidal fraction in the solutions from sorption experiments, and around 20% of TNT in the effluent from the transport experiments. Results demonstrate that OC rich soils may enhance sorption and delay transport of TNT, RDX and HMX compared to clay-rich soils. Further, transport of TNT may be associated with soil colloid mobilization.
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Affiliation(s)
- Prasesh Sharma
- Oak Ridge National Laboratory, Environmental Sciences Division, Oak Ridge, TN 37831, USA
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Lin KS, Dehvari K, Hsien MJ, Hsu PJ, Kuo H. Degradation of TNT, RDX, and HMX Explosive Wastewaters Using Zero-Valent Iron Nanoparticles. PROPELLANTS EXPLOSIVES PYROTECHNICS 2013. [DOI: 10.1002/prep.201200205] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Lamichhane KM, Babcock RW, Turnbull SJ, Schenck S. Molasses enhanced phyto and bioremediation treatability study of explosives contaminated Hawaiian soils. JOURNAL OF HAZARDOUS MATERIALS 2012; 243:334-339. [PMID: 23164624 DOI: 10.1016/j.jhazmat.2012.10.043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 10/20/2012] [Accepted: 10/20/2012] [Indexed: 06/01/2023]
Abstract
A 15-week treatability study was conducted in a greenhouse to evaluate the potential effects of molasses on the bioremediation and phytoremediation potential of Guinea Grass (Panicum maximum) for treating energetic contaminated soil from the open burn/open detonation area of the Makua Military Reservation, Oahu, HI (USA). The energetics in the soil were royal demolition explosive (RDX) and high-melting explosive (HMX). Among the 6 treatments employed in this study, enhanced removal of RDX was observed from treatments that received molasses and went to completion. The RDX degradation rates in treatments with molasses diluted 1:20 and 1:40 were comparable suggesting that the lower dose worked as well as the higher dose. Treatments without molasses degraded RDX slowly and residuals remained after 15 weeks. The bacterial densities in molasses-treated units were much greater than those without molasses. Phytoremediation alone seems to have little effect on RDX disappearance. For HMX, neither bioremediation nor phytoremediation was found to be useful in reducing the concentration within the experimental period. The concentrations of nitrogen and phosphorous in the soil did not change significantly during the experiment, however, a slight increase in soil pH was observed in all treatments. The study showed that irrigating with diluted molasses is effective at enhancing RDX degradation mainly in the root zone and just below it. The long term sustainability of active training ranges can be enhanced by bioremediation using molasses treatments to prevent RDX deposited by on-going operations from migrating through the soil to groundwater and off-site.
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Affiliation(s)
- Krishna M Lamichhane
- University of Hawaii, Department of Civil and Environmental Engineering, 2540 Dole Street, Holmes 283, Honolulu, HI 96822, USA.
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