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Wood JP, Silvestri E, Pirhalla M, Serre SD, Calfee MW, McConkey K, Boe T, Monge M, Aslett D, Abdel-Hady A. Fate and transport of viable Bacillus anthracis simulant spores in ambient air during a large outdoor decontamination field exercise. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2024:1-14. [PMID: 38775962 DOI: 10.1080/10962247.2024.2359122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 05/06/2024] [Indexed: 06/26/2024]
Abstract
The Wide Area Demonstration (WAD) was a field exercise conducted under the U.S. EPA's Analysis of Coastal Operational Resiliency program, in conjunction with the U.S. Department of Homeland Security and the U.S. Coast Guard. The purpose of the WAD was to operationalize at field scale aspects of remediation activities that would occur following an outdoor release of Bacillus anthracis spores, including sampling and analysis, decontamination, data management, and waste management. The WAD was conducted in May 2022 at Fort Walker (formerly known as Fort A.P. Hill) and utilized Bacillus atrophaeus as a benign simulant for B. anthracis. B. atrophaeus spores were inoculated onto the study area at the beginning of the study, and air samples were collected daily during each of the different phases of the WAD using Dry Filter Units (DFUs). Ten DFU air samplers were placed at the perimeter of the study area to collect bioaerosols onto two parallel 47-mm diameter polyester felt filters, which were then subsequently analyzed in a microbiological laboratory for the quantification of B. atrophaeus. The study demonstrated the use of DFUs as a rugged and robust bioaerosol collection device. The results indicated that the highest B. atrophaeus spore air concentrations (up to ~ 5 colony forming units/m3) occurred at the beginning of the demonstration (e.g. during inoculation and characterization sampling phases) and generally downwind from the test site, suggesting transport of the spores was occurring from the study area. Very few B. atrophaeus spores were detected in the air after several weeks and following decontamination of exterior surfaces, thus providing an indication of the site decontamination procedures' effectiveness. No B. atrophaeus spores were detected in any of the blank or background samples.Implications: Following an incident involving a release of Bacillus anthracis spores or other biological threat agent into the outdoor environment, understanding the factors that may affect the bioagent's fate and transport can help predict viable contaminant spread via the ambient air. This paper provides scientific data for the first time on ambient air concentrations of bacterial spores over time and location during different phases of a field test in which Bacillus atrophaeus (surrogate for B. anthracis) spores were released outdoors as part of a full-scale study on sampling and decontamination in an urban environment. This study advances the knowledge related to the fate and transport of bacterial spores (such as those causing anthrax disease) as an aerosol in the outdoor environment over the course of three weeks in a mock urban environment and has exposure and health risk implications. The highest spore air concentrations occurred at the beginning of the study (e.g. during inoculation of surfaces and characterization sampling), and in the downwind direction, but diminished over time; few B. atrophaeus spores were detected in the air after several weeks and following decontamination. Therefore, in an actual incident, potential reaerosolization of the microorganism and subsequent transport in the air during surface sampling and remediation efforts should be considered for determining exclusion zone locations and estimating potential risk to neighboring communities. The data also provide evidence suggesting that the large-scale decontamination of outdoor surfaces may reduce air concentrations of the bioagent, which is important since exposure of B. anthracis via inhalation is a primary concern.
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Affiliation(s)
- Joseph P Wood
- Office of Research and Development, Center for Environmental Solutions and Emergency Response, United States Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Erin Silvestri
- Office of Research and Development, Center for Environmental Solutions and Emergency Response, United States Environmental Protection Agency, Cincinnati, OH, USA
| | - Michael Pirhalla
- Office of Research and Development, Center for Environmental Solutions and Emergency Response, United States Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Shannon D Serre
- Office of Emergency Management, United States Environmental Protection Agency, Research Triangle Park, NC, USA
| | - M Worth Calfee
- Office of Research and Development, Center for Environmental Solutions and Emergency Response, United States Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Katrina McConkey
- Office of Emergency Management, United States Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Timothy Boe
- Office of Research and Development, Center for Environmental Solutions and Emergency Response, United States Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Mariela Monge
- Homeland Security Research Department, Jacobs Technology, Inc., Research Triangle Park, NC, USA
| | - Denise Aslett
- Homeland Security Research Department, Jacobs Technology, Inc., Research Triangle Park, NC, USA
| | - Ahmed Abdel-Hady
- Homeland Security Research Department, Jacobs Technology, Inc., Research Triangle Park, NC, USA
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Boening-Ulman KM, Mikelonis AM, Heckman JL, Calfee MW, Ratliff K, Youn S, Smith JS, Mitchell CE, Hunt WF, Winston RJ. The potential to manage releases of Bacillus anthracis using bioretention and a high flow media filter: Results of simulated runoff testing with tracer spores Bacillus globigii. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 354:120286. [PMID: 38354613 DOI: 10.1016/j.jenvman.2024.120286] [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: 09/08/2023] [Revised: 01/19/2024] [Accepted: 02/02/2024] [Indexed: 02/16/2024]
Abstract
The threat of bioterrorism has spurred research on the decontamination and containment of different agents. Anthrax [causative agent Bacillus anthracis (Ba)] is a disease that can lead to severe infections within human and animals, particularly when inhaled. This research investigated the use of spore-contaminated simulated runoff events into stormwater control measures (SCMs), which are designed to retain and improve the quality of runoff and may have the potential to filter and contain the spores. In this study, the effectiveness of a bioretention cell (BRC) and high flow media filter (HFMF) in Huron, Ohio, were evaluated for removal of Bacillus globigii (Bg) spores (a harmless cognate of Ba). Three 4-8 mm simulated runoff events were created for each SCM using a fire hydrant and Bg spores were injected into the runoff upstream of the SCM inlets. The BRC significantly (p < 0.001) outperformed the HFMF in reducing Bg concentrations and loads, with an average load reduction of 1.9 log (∼99% reduction) compared to 0.4 (∼60% reduction), respectively. A probable critical design factor leading to these differences was the infiltration rate of the media and subsequent retention time within the filters, which was supported by similar disparities in suspended solids reductions. Differences in spore removal may also have been due to particle size distribution of the HFMF, which was more gravelly than the bioretention cell. At 3 and 6 months after the-simulated runoff tests, soil samples taken from both SCMs, yielding detectable Bg spores within the top 15 cm of media, with increased spore concentrations where ponding occurred for longer durations during the tests. This suggests that forebays and areas near inlets may be hotspots for spore cleanup in a real-world bioterrorism incident.
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Affiliation(s)
- Kathryn M Boening-Ulman
- Department of Food, Agricultural and Biological Engineering, The Ohio State University, 590 Woody Hayes Dr., Columbus, OH, 43210, USA.
| | - Anne M Mikelonis
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, 109 T.W. Alexander Dr., Research Triangle Park, NC, 27711, USA
| | - J Lee Heckman
- APTIM Government Solutions, 1600 Gest St., U.S. Environmental Protection Agency Test and Evaluation Facility, Cincinnati, OH, 45204, USA
| | - M Worth Calfee
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, 109 T.W. Alexander Dr., Research Triangle Park, NC, 27711, USA
| | - Katherine Ratliff
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, 109 T.W. Alexander Dr., Research Triangle Park, NC, 27711, USA
| | - Sungmin Youn
- Department of Civil Engineering, Marshall University, Huntington, WV, 25755, USA
| | - Joseph S Smith
- Department of Food, Agricultural and Biological Engineering, The Ohio State University, 590 Woody Hayes Dr., Columbus, OH, 43210, USA
| | - Caleb E Mitchell
- Department of Biological and Agricultural Engineering, North Carolina State University, 3100 Faucette Dr., Raleigh, NC, 27695, USA
| | - William F Hunt
- Department of Biological and Agricultural Engineering, North Carolina State University, 3100 Faucette Dr., Raleigh, NC, 27695, USA
| | - Ryan J Winston
- Department of Food, Agricultural and Biological Engineering, The Ohio State University, 590 Woody Hayes Dr., Columbus, OH, 43210, USA; Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, 2070 Neil Ave., Columbus, OH, 43210, USA
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Mikelonis AM, Hall J, Dunn CA, McArthur T, Wiley G, Hintz CL, Steenbock J, Serre S, Calfee MW, Pirhalla M. Monitoring spore washoff during a biological contamination incident response using automated stormwater samplers and sensors to predict contamination movement. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 897:165307. [PMID: 37414183 DOI: 10.1016/j.scitotenv.2023.165307] [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: 04/11/2023] [Revised: 06/30/2023] [Accepted: 07/02/2023] [Indexed: 07/08/2023]
Abstract
This study examined the washoff of Bacillus globigii (Bg) spores from concrete, asphalt, and grass surfaces by stormwater. Bg is a nonpathogenic surrogate for Bacillus anthracis, which is a biological select agent. Areas (2.74 m × 7.62 m) of concrete, grass, and asphalt were inoculated twice at the field site during the study. Spore concentrations were measured in runoff water after seven rainfall events (1.2-65.4 mm) and complimentary watershed data were collected for soil moisture, depth of water in collection troughs, and rainfall using custom-built telemetry units. An average surface loading of 107.79 Bg spores/m2 resulted in peak spore concentrations in runoff water of 102, 260, and 4.1 CFU/mL from asphalt, concrete, and grass surfaces, respectively. Spore concentrations in the stormwater runoff were greatly reduced by the third rain event after both inoculations, but still detectable in some samples. When initial rainfall events occurred longer after the initial inoculation, the spore concentrations (both peak and average) in the runoff were diminished. The study also compared rainfall data from 4 tipping bucket rain gauges and a laser disdrometer and found they performed similarly for values of total rainfall accumulation while the laser disdrometer provided additional information (total storm kinetic energy) useful in comparing the seven different rain events. The soil moisture probes are recommended for assistance in predicting when to sample sites with intermittent runoff. Sampling trough level readings were critical to understanding the dilution factor of the storm event and the age of the sample collected. Collectively the spore and watershed data are useful for emergency responders faced with remediation decisions after a biological agent incident as the results provide insight into what equipment to deploy and that spores may persist in runoff water at quantifiable levels for months. The spore measurements are also a novel dataset for stormwater model parameterization for biological contamination of urban watersheds.
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Affiliation(s)
- Anne M Mikelonis
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, Homeland Security and Materials Management Division, Research Triangle Park, NC, United States of America.
| | - John Hall
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, Homeland Security and Materials Management Division, Cincinnati, OH, United States of America
| | - Chris A Dunn
- U.S. Coast Guard, Base Elizabeth City, Elizabeth City, NC, United States of America
| | - Timothy McArthur
- Science Systems and Applications Inc., Research Triangle Park, NC, United States of America
| | - Garrett Wiley
- Jacobs Technology Inc., Research Triangle Park, NC, United States of America
| | - Chelsea L Hintz
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, Homeland Security and Materials Management Division, Cincinnati, OH, United States of America
| | - Joshua Steenbock
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, Homeland Security and Materials Management Division, Cincinnati, OH, United States of America
| | - Shannon Serre
- U.S. Environmental Protection Agency, Office of Land and Emergency Management, Consequence Management Advisory Division, Research Triangle Park, NC, United States of America
| | - Michael Worth Calfee
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, Homeland Security and Materials Management Division, Research Triangle Park, NC, United States of America
| | - Michael Pirhalla
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, Homeland Security and Materials Management Division, Research Triangle Park, NC, United States of America
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Vo PH, Key TA, Le TH, McDonough JT, Porman S, Fiorenza S, Nguyen HT, Dao VT, Mueller JF, Thai PK. Evaluation of sealants to mitigate the release of per- and polyfluoroalkyl substances (PFAS) from AFFF-impacted concrete: Characterization and forecasting. WATER RESEARCH X 2023; 20:100195. [PMID: 37637861 PMCID: PMC10448196 DOI: 10.1016/j.wroa.2023.100195] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 08/06/2023] [Accepted: 08/07/2023] [Indexed: 08/29/2023]
Abstract
Per- and polyfluoroalkyl substances (PFAS) within concrete pads impacted by historical firefighting training using aqueous film-forming foam (AFFF) may be potential secondary sources of PFAS due to surficial leaching. This study aimed to (i) characterize the effectiveness of two commercially available sealants (Product A and Product B) in mitigating leaching of five PFAS (e.g., PFOS, PFOA, PFHxS, PFHxA, 6:2 FTS) from concrete surfaces at the laboratory-scale, and (ii) develop a model to forecast cumulative leaching of the same five PFAS over 20 years from sealed and unsealed concrete surfaces. Laboratory trials demonstrated that both sealants reduced the surficial leaching of the five PFAS studied, and Product B demonstrated a comparatively greater reduction in surface leaching than Product A as measured against unsealed controls. The cumulative PFOS leaching from an unsealed concrete surface is estimated by the model to be about 400 mg/m2 over 20 years and reached asymptotic conditions after 15 years. In contrast, the model output suggests asymptotic conditions were not achieved within the modeled time of 20 years after sealing with Product A and 85% of PFOS was predicted to have leached (∼340 mg/m2). Negligible leaching of PFOS after sealing with Product B was observed ( < 5 × 10-9 mg/m2). Results from modeled rainfall scenarios suggest PFAS leachability is reduced from sealed versus unsealed AFFF-impacted concrete surfaces.
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Affiliation(s)
- Phong H.N. Vo
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Queensland, 4102, Australia
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, 15 Broadway, Ultimo, NSW 2007, Australia
| | - Trent A. Key
- ExxonMobil Environmental and Property Solutions Company, Spring, TX 77389, USA
- ExxonMobil Biomedical Sciences Inc., Spring, TX 77389, USA
| | - Tu Hoang Le
- Nong Lam University Ho Chi Minh city, Ho Chi Minh City, Vietnam
| | | | - Scott Porman
- Mobil Oil Australia, Melbourne, VIC 3008, Australia
| | | | - Hong T.M. Nguyen
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Queensland, 4102, Australia
| | - Vinh T.N. Dao
- School of Civil Engineering, The University of Queensland, Queensland, 4102, Australia
| | - Jochen F. Mueller
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Queensland, 4102, Australia
| | - Phong K. Thai
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Queensland, 4102, Australia
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Yuan L, Mikelonis AM, Yan E. Using SWMM for emergency response planning: A case study evaluating biological agent transport under various rainfall scenarios and urban surfaces. JOURNAL OF HAZARDOUS MATERIALS 2023; 458:131747. [PMID: 37454488 DOI: 10.1016/j.jhazmat.2023.131747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/11/2023] [Accepted: 05/29/2023] [Indexed: 07/18/2023]
Abstract
To assist in emergency preparedness for a biological agent terrorist attack or accidental pathogen release, potential contaminant levels and migration pathways of spores spread by urban stormwater were evaluated using a Storm Water Management Model (SWMM) of U.S. Coast Guard Base Elizabeth City, North Carolina. The high temporal-spatial resolution SWMM model was built using spore concentrations in stormwater runoff from asphalt, grass, and concrete collected from a point-scale field study. The subsequent modeled contamination scenarios included a notional plume release and point releases mimicking the field study under three rainfall conditions. The rainfall scenarios included a 6-hour natural rainfall event on Dec. 8, 2021 and two design storms (2-year and 100-year events). The observed spore concentrations from asphalt and concrete from the actual field experiment were applied to calibrate the washoff parameters in the SWMM model, using an exponential washoff function. The calibrated washoff coefficient (c1) and exponent (c2) were 0.01 and 1.00 for asphalt, 0.05 and 1.45 for grass, and 2.45 and 1.00 for concrete, respectively. The calibrated SWMM model simulated spore concentrations in runoff at times and magnitudes similar to the field study data. In the point release modeled scenario, the concrete surface generated 55.6% higher average spore concentrations than asphalt. Similarly, in the field experiment, a 175% (p < 0.05) higher average spore concentration in surface runoff was observed from concrete than from asphalt. This study demonstrates how SWMM may be used to evaluate spore washoff from urban surfaces under different precipitation amounts, intensities, and durations, and how visualized spatial migration pathways in stormwater runoff may be used for emergency planning and remediation.
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Affiliation(s)
- Lifeng Yuan
- US EPA Office of Research and Development, Center for Environmental Solutions and Emergency Response, Homeland Security Materials Management Division, Durham, NC, USA.
| | - Anne M Mikelonis
- US EPA Office of Research and Development, Center for Environmental Solutions and Emergency Response, Homeland Security Materials Management Division, Durham, NC, USA
| | - Eugene Yan
- Environmental Science Division of Argonne National Laboratory, Argonne, IL, USA
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Jeong H, Ra K. Pollution and ecological risk assessments for heavy metals in coastal, river, and road-deposited sediments from Apia City in Upolu Island, Samoa. MARINE POLLUTION BULLETIN 2023; 188:114596. [PMID: 36706545 DOI: 10.1016/j.marpolbul.2023.114596] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/05/2023] [Accepted: 01/06/2023] [Indexed: 06/18/2023]
Abstract
This study was the first to investigate the pollution and ecological risks of heavy metals in coastal, river/stream and road-deposited sediments (RDS) from Apia in Samoa. Cr and Ni concentrations in sediment samples were higher than those of other metals. River sediments and RDS had relatively high EF values around the intensive commercial areas, with a moderate to significant enrichment of Cu, Zn, Cd, and Pb. The results indicate that Cr and Ni have a natural origin from volcanic parent materials, while Cu, Zn, Cd, and Pb originated from anthropogenic activities, such as traffic emissions and the discharge of municipal wastewater. The assessments of pollution and ecological risk revealed that coastal sediments adjacent to the river are anthropogenically contaminated and present a moderate ecological risk. This study demonstrates that metals that have accumulated in the urban impermeable layer and river/stream bed have flowed into the coastal environment through runoff.
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Affiliation(s)
- Hyeryeong Jeong
- Ifremer, RBE/CCEM, F-44000 Nantes, France; Marine Environmental Research Center, Korea Institute of Ocean Science and Technology (KIOST), Busan 49111, Republic of Korea
| | - Kongtae Ra
- Marine Environmental Research Center, Korea Institute of Ocean Science and Technology (KIOST), Busan 49111, Republic of Korea; Department of Ocean Science (Oceanography), KIOST School, University of Science and Technology (UST), Daejeon 34113, Republic of Korea.
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Ratliff K, Abdel-Hady A, Monge M, Mikelonis A, Touati A. Impact of filter material and holding time on spore sampling efficiency in water. Lett Appl Microbiol 2023; 76:ovad005. [PMID: 36705271 PMCID: PMC10599418 DOI: 10.1093/lambio/ovad005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 12/28/2022] [Accepted: 01/12/2023] [Indexed: 01/15/2023]
Abstract
Bacillus anthracis and other environmentally persistent pathogens pose a significant threat to human and environmental health. If contamination is spread over a wide area (e.g. resulting from a bioterrorism or biowarfare incident), readily deployable and scalable sample collection methods will be necessary for rapidly developing and implementing effective remediation strategies. A recent surge in environmental (eDNA) sampling technologies could prove useful for quantifying the extent and levels of contamination from biological agents in environmental and drinking water. In this study, three commonly used membrane filtration materials (cellulose acetate, cellulose nitrate, and nylon) were evaluated for spore filtration efficiency, yielding recoveries from 17%-68% to 25%-117% for high and low titer samples, respectively, where cellulose nitrate filters generated the highest recoveries. A holding time test revealed no statistically significant differences between spore recoveries when analyzed at the specified timepoints, suggesting that eDNA filter sampling techniques can yield and maintain a relatively high recovery of spores for an extended period of time between filtration and analysis without a detrimental impact on spore recoveries. The results shown here indicate that emerging eDNA technologies could be leveraged for sampling following a wide-area contamination incident and for other microbiological water sampling applications.
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Affiliation(s)
- Katherine Ratliff
- Center for Environmental Solutions and Emergency Response, Office of Research and Developmen, Environmental Protection Agency, Research Triangle Park, NC 27709, USA
| | | | - Mariela Monge
- Consolidated Safety Services, Inc., Research Triangle Park, NC 27709, USA
| | - Anne Mikelonis
- Center for Environmental Solutions and Emergency Response, Office of Research and Developmen, Environmental Protection Agency, Research Triangle Park, NC 27709, USA
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Mikelonis AM, Fuller C, Ratliff K, Touati A, Calfee MW. Influence of wash aids on Bacillus spore removal from an asphalt parking lot using two spray-based washing methods. J Appl Microbiol 2022; 132:2773-2780. [PMID: 34878661 PMCID: PMC9808591 DOI: 10.1111/jam.15405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/23/2021] [Accepted: 12/06/2021] [Indexed: 01/07/2023]
Abstract
AIMS The goal of this study was to measure the removal efficacy of Bacillus atrophaeus spores from a parking lot using spray-based washing methods (a pressure washer and a garden hose) and wash aids. B. atrophaeus is a commonly used nonpathogenic surrogate for B. anthracis, the causative agent of anthrax and a deadly bioterrorism agent that would cause major disruptions and damage to public health should it be disseminated over an urban area. METHODS AND RESULTS Five wash aids (1 mM sodium chloride, an Instant Ocean® seawater solution, 0.01% Tween 20, 0.01% sodium dodecyl sulfate, and unamended tap water) were used along with two different spray sequences in this study. Across all treatment conditions, 3.7-6.4 log10 colony forming unit were recovered in the runoff water, and 0.15%-23% of spores were removed from the surface of the parking lot. CONCLUSIONS Pressure washing removed more spores than the garden hose, and for both types of washing methods, the first pass removed more spores than the subsequent passes. The Instant Ocean and Tween 20 wash aids were found to significantly increase the percentage of spore removal when using the pressure washer, but the overall increase was only 1%-2% compared to the tap water alone. SIGNIFICANCE AND IMPACT OF STUDY This study provides public officials and emergency responders with baseline spore physical removal information for situations where a corrosive disinfectant might have a negative impact on the environment and washing is being considered as an alternative remediation approach.
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Affiliation(s)
- Anne M. Mikelonis
- Homeland Security Materials Management Division, Center for Environmental Solutions and Emergency Response, U.S. EPA Office of Research and Development, Durham, North Carolina, USA
| | - Christopher Fuller
- Watershed & Ecosystem Characterization Division, Center for Environmental Measurement and Modeling, U.S. EPA Office of Research and Development, Durham, North Carolina, USA
| | - Katherine Ratliff
- Homeland Security Materials Management Division, Center for Environmental Solutions and Emergency Response, U.S. EPA Office of Research and Development, Durham, North Carolina, USA
| | | | - Michael W. Calfee
- Homeland Security Materials Management Division, Center for Environmental Solutions and Emergency Response, U.S. EPA Office of Research and Development, Durham, North Carolina, USA
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