United States Environmental Protection Agency EPA/600/R-10/080 | September 2010 | www.epa.gov/ord Evaluation of Liquid and Foam Technologies for the Inactivation of Bacillus anthracis Spores on Topsoil INVESTIGATION REPORT Office of Research and Development National Homeland Security Research Center ------- ------- Evaluation of Liquid and Foam Technologies for the Decontamination of Bacillus anthracis Spores on Topsoil INVESTIGATION REPORT U.S. ENVIRONMENTAL PROTECTION AGENCY OFFICE OF RESEARCH AND DEVELOPMENT NATIONAL HOMELAND SECURITY RESEARCH CENTER RESEARCH TRIANGLE PARK, NC 27711 Office of Research and Development National Homeland Security Research Center ------- ------- Disclaimer The U.S. Environmental Protection Agency (EPA), through its Office of Research and Development. National Homeland Security Research Center, funded and directed this investigation through a Blanket Purchase Agreement under General Services Administration contract number GS23F0011L-3 with Battelle. This document has been subjected to the Agency's review and has been approved for publication. Note that approval docs not signify that the contents necessarily reflect the views of the Agency. Mention of trade names or commercial products in this document or in the methods referenced in this document docs not constitute endorsement or recommendation for use. Questions concerning this document or its application should be addressed to: Joseph P. Wood National Homeland Security Research Center Office of Research and Development (E-343-06) U.S. Environmental Protection Agency 109 T.YV. Alexander Dr. Research Triangle Park, NC 27711 (919) 541-5029 wood.ioe@.epa. gov If you have difficulty accessing this PDF document, please contact Kathy Nickel fNickel.Kathv@. eDa.gov) or Amelia McCall (McCalL Amelia@.epa.gov) for assistance. ------- Acknowledgments Contributions of the following individuals and organizations to the development of this document arc acknowledged. United States Environmental Protection Agency (EPA) Michael Ottlingcr Timothy Curry Leroy Mickclscn Battelle Peer Reviewers Peter Set low. University of Connecticut Michele Burgess. EPA Office of Emergency Management Frank Schacfcr, EPA National Homeland Security Research Center ------- Contents Disclaimer iii Acknowledgments iv Abbreviations/Acronyms viii Executive Summary ix 1.0 Introduction 1 2.0 Technology Description 3 3.0 Summary of Test Procedures 5 3.1 Preparation and Analysis of Test Coupons 5 3.2 Decontamination Efficacy 7 4.0 Quality Assurance/Quality Control 9 4.1 Equipment Calibration 9 4.2 QC Results 9 4.3 Audits 9 4.3.1 Performance Evaluation Audit 9 4.3.2 Technical Systems Audit 9 4.3.3 Data Quality Audit 9 4.4 Test/QA Plan Amendments and Deviations 9 4.5 QA/QC Reporting 9 4.6 Data Review 9 5.0 pH-Aincnded Ultra Clorox Germicidal Bleach Test Results 11 5.1 QC Results 11 5.2 Deco nta mi nat io n Efficacy 11 5.3 Other Factors 11 5.3.1 Operator Control 11 5.3.2 Technology Spray Deposition 12 5.3.3 Neutralization Methodology 12 6.0 CASCAD SDF ( Allen-Vanguard) Test Results 15 6.1 QC Results 15 6.2 Deco nta mi nat io n E fficacy 15 6.3 Other Factors 15 6.3.1 Operator Control 15 6.3.2 Technology Spray Deposition 16 6.3.3 Neutralization Methodology 16 ------- 7.0 Oxonia Active (Ecolab) Test Results 19 7.1 QC Results 19 7.2 Decontamination Efficacy 19 7.3 Other Factors 19 7.3.1 Operator Control 19 7.3.2 Technology Spray Deposition 20 7.3.3 Neutralization Methodology 20 8.0 Klo/ur (FMC Corporation) Test Results 23 8.1 QC Results 23 8.2 Decontamination Efficacy 23 8.3 Other Factors 24 8.3.1 Operator Control 24 8.3.2 Technology Deposition 24 8.3.3 Neutralization Methodology 24 9.0 Performance Summary 27 9.1 pH-Aincnded Ultra Clorox Germicidal Bleach Results 27 9.2 CASCAD SDF Results 27 9.3 Oxonia Active Results 27 9.4 Klo/ur Results 27 10.0 References 29 Appendices - Technology Descriptions and Application Procedures for the Evaluated Decontaminants A pH-Ainended Bleach Description and Application Procedure 31 B C ASC AD SDF Description and Application Procedure 33 C Oxonia Active Description and Application Procedure 35 D Klo/ur Description and Application Procedure 37 ------- List of Tables Tabic E-l. Summary of Quantitative Efficacy of Each Dccontaminant on Topsoil Coupons x Tabic 2-1. Technology Information 3 Tabic 5-1. Inactivation of Bacillus anthracis Ames Spores on Topsoil - pH-Amcndcd Ultra Clorox Germicidal Bleach 11 Table 5-2. Neutralization Testing with Bacillus anthracis (Ames) Spores on Topsoil for pH- A mended Ultra Clorox Germicidal Bleach (60 Minute Contact Time, Volume Equal to 4 Applications) 12 Table 5-3. Neutralization Testing with Bacillus anthracis (Ames) Spores on Topsoil for pH- Amended Ultra Clorox Germicidal Bleach (120-Minute Contact Time, Volume Equal to 8 Applications) 13 Table 6-1. Inactivation of Bacillus anthracis Ames Spores on Topsoil - CASCAD SDF 15 Table 6-2. Ncutrali/ation Testing with Bacillus anthracis (Ames) Spores on Topsoil for CASCAD SDF (60 Minute Contact Time, Volume Equal to 2 Applications) 16 Table 6-3. Ncutrali/ation Testing with Bacillus anthracis (Ames) Spores on Topsoil for CASCAD SDF (120 Minute Contact Time, Volume Equal to 4 Applications) 17 Table 7-1. Inactivation of Bacillus anthracis Ames Spores on Topsoil - Oxonia Active 19 Table 7-2. Ncutrali/ation Testing with Bacillus anthracis (Ames) Spores on Topsoil for Oxonia Active (60 Minute Contact Time, Volume Equal to 6 Applications) 20 Table 7-3. Ncutrali/ation Testing with Bacillus anthracis (Ames) Spores on Topsoil for Oxonia Active (120 Minute Contact Time, Volume Equal to 12 Applications) 21 Table 8-1. Inactivation of Bacillus anthracis Ames Spores on Topsoil - Klo/ur 23 Table 8-2. Ncutrali/ation Testing with Bacillus anthracis (Ames) Spores on Topsoil for Klo/ur (24 Hour Contact Time, Volume Equal to 6 Applications) 24 Table 8-3. Ncutrali/ation Testing with Bacillus anthracis (Ames) Spores on Topsoil for Klo/ur (48 Hour Contact Time, Volume Equal to 6 Applications) 25 ------- List of Abbreviations/Acronyms ASTM American Society for Testing and Materials B. anthracis Bacillus anthracis (Ames strain) BBRC Battclle Biomedical Research Center BSC biosafety cabinet C Celsius CFU colony-forming unit(s) CI confidence interval cm centimeter EPA U.S. Environmental Protection Agency g gram hr hour L liter M molar min minute mL milliliter NHSRC National Homeland Security Research Center NIST National Institute of Standards and Technology OPP EPA Office of Pesticide Programs PBS phosphate-buffered saline PPm parts per million psi pounds per square inch OA quality assurance QC quality control QMP quality management plan RH relative humidity SD standard deviation SDF surface decontamination foam SE standard error SFVV sterile filtered water (cell-culture grade) STS sodium thiosulfate TOPO Task Order Project Officer TSA technical systems audit ------- Executive Summary The U.S. Environmental Protection Agency's (EPA) National Homeland Security Research Center (NHSRC) helps to protect human health and the environment from adverse impacts of terrorist acts by carrying out performance tests on homeland security technologies. This report describes a study in which liquid and foam technologies were evaluated for decontaminating test coupons of topsoil containing Bacillus anthracis spores. Experimental Procedures. For some tests, topsoil coupons were prepared by filling a Parafilm®-lined 3.5 cm diameter 1 cm high Petri dish with uncompacted commercially available topsoil. For most tests, which involved several applications of a decontaminant, the same amount of uncompacted topsoil was placed into a 3.4 cm high Teflon beaker of the same diameter as the Petri dish, in order to effectively capture all of the applied decontaminant. The topsoil used was a commercial garden topsoil. determined by analysis to be approximately 29% moisture by weight, with an organic content of approximately 6% on a dry weight basis. For testing, topsoil coupons were "contaminated" by inoculation with the biological agent Bacillus anthracis (Ames). The technologies evaluated for their ability to inactivate B. anthracis (Ames) on topsoil coupons were: • pH-Aiiiciided Ultra Clorox® Germicidal bleach (diluted with commercial cell-culture grade sterile filtered water (SFVV) and 5% acetic acid to obtain pH-amended solution) • Allen-Vanguard's CASCAD'" Surface Decontamination Foam (SDF) • Ecolab Inc.'s Oxonia Active* • FMC Corporation's Klozur™ (activated with hydrogen peroxide (H202)) This evaluation was designed to determine the quantitative decontamination efficacy of each technology, in terms of the reduction in the number of viable organisms in the topsoil coupons (log reduction). Each decontaminant technology was tested with two different contact times. C ASC AD SDF was applied to topsoil coupons according to the vendor's instructions, using a dual-compartment spray bottle provided by the vendor. Oxonia Active was applied according to the vendor's instructions, using a conventional hand- pumped household garden sprayer. The pH-amcnded Ultra Clorox Germicidal bleach was applied according to an application procedure developed by EPA and Battclle. using the same type of conventional hand- pumped household garden sprayer. For these three decontaminants, the two contact times were 60 and 120 minutes. Spray distance, humidity, and temperature were the same for all applications of these three decontaminants. Klo/ur is designed for use as a soil remediation treatment, and consequently a different treatment approach was used. Klo/ur solution was mixed with the topsoil in a Teflon beaker, and an equal volume of an activating solution of hydrogen peroxide was then immediately mixed in. An initial test of Klo/ur was conducted with a 24-hour contact time, and the second contact time of 48 hours was then chosen based on the results of that test. Technical descriptions and preparation and application procedures (including the spray device, contact time, and reapplication rate) for all the decontaminants tested are included as appendices to this report. Results: Application procedures and results for the four decontaminants arc summarized in the following paragraphs. pH-Aiiiciided Ultra Clorox Germicidal bleach - In the first test of this decontaminant it was applied to the test coupons until they were fully wetted, and then reapplied at 15-minute intervals for a total of four applications in a 60-minute contact time. In the second test of this decontaminant it was applied to the test coupons until they were fully wetted, and then reapplied at 15-minute intervals for a total of eight applications in a 120-minute contact time. In addition, after each of the eight applications in the second test, the topsoil and the applied pH-amended Ultra Clorox Germicidal bleach were mixed together using a glass stirring rod. Quantitative efficacy for B. anthracis (Ames) was 0.03 log reduction with the 60-minute contact time and 0.94 log reduction with the 120-minute contact time. CASCAD SDF - In the first test of this decontaminant it was applied to the test coupons until they were fully covered with foam, and then reapplied 30 minutes later for a total of two applications in a 60-minute contact time. In the second test of this decoiitamiiiant it was applied to the test coupons until they were fully covered with foam, and then reapplied at 30-minute intervals for a total of four applications in a 120-iniiiutc contact time. Quantitative efficacy for B. anthracis (Ames) was 0.59 log reduction with the 60-iniiiutc contact time and 1.13 log reduction with the 120-iniiiutc contact time. Oxonia Active - In the first test of this decontaminant. it was applied to the test coupons until they were fully ------- wetted, and then reapplied at 10-minute intervals for a total of six applications in a 60-minute contact time. In the second test of this dccontaniinant it was applied to the test coupons until they were fully wetted, and then reapplied at 10-minute intervals for a total of 12 applications in a 120-minute contact time. In addition, after each of the 12 applications in the second test, the topsoil and the applied Oxonia Active were mixed together using a glass stirring rod. Quantitative efficacy for B. anthracis (Ames) was 0.58 log reduction with the 60-minute contact time and 1.04 log reduction with the 120-minute contact time. Klo/ur - In the first test of this dccontaniinant 1 niL of a Klo/ur solution and 1 niL of a H202 activating solution were added to each topsoil coupon every 60 minutes, and mixed with the topsoil using a glass stirring rod. This process was repeated until six total applications were made. The dccontaniinant then remained in contact with the topsoil coupons until 24 hours had elapsed since the first application. In the second test, the same schedule and application and mixing procedures were followed for the six applications, but the total contact time was 48 hours. Quantitative efficacy for B. anthracis (Ames) was 1.65 log reduction with the 24-hour contact time and 3.50 log reduction with the 48-hour contact time. Table E-l summarizes the application procedures and quantitative efficacy results (with 95% confidence intervals) for all dccontaniinants at both contact times. Table E-l. Summary of Quantitative Efficacy of Each Decontaminant on Topsoil Coupons Decontaminant Total Contact Time (minutes) Number of Applications Mass of Decontaminant Applied (g) Stirring (Y/N)a Quantitative Efficacy as Log Reduction (± 95% CI)" pH-Amended Ultra Clorov Germicidal Bleach 60 minutes 4 2.6 N 0.03 (±0.15) 120 minutes 8 3.6 Y 0.94 (±0.10) CASCADSDF 60 minutes 2 2.9 N 0.59 (±0.04) 120 minutes 4 6.5 N 1.13 (±0.12) Oxonia Active 60 minutes 6 4.0 N 0.58 (±0.19) 120 minutes 12 7.1 Y 1.04 (±0.10) Klozur (activated with "A> 24 hours 6 12 Y 1.65 (±0.14) 48 hours 6 12 Y 3.50 (±0.40) a Stirring means mixing together of topsoil and applied decontaminant after each application, b CI = confidence interval. Efficacy was slightly better with the 120-minute contact time than with the 6()-niinutc contact time for pH- anicnded Ultra Clorox Germicidal bleach, CASCAD SDF, and Oxonia Active. However, efficacy with these three dccontaniinants never exceeded about 1 log reduction, even with several applications onto the topsoil coupons. With Klo/ur. efficacy was substantially greater with the 48-hour contact time than with the 24- hour contact time, but both Klo/ur efficacy results were significantly higher than any efficacy result with the ------- 1.0 Introduction NHSRC works in partnership with recognized testing organizations; with stakeholder groups consisting of buyers, vendor organizations, scientists, engineers, and permitters; and with participation of individual technology developers in carrying out performance tests on homeland security technologies. In response to the needs of stakeholders, NHSRC evaluates the performance of innovative homeland security technologies by developing test plans, conducting evaluations, collecting and analyzing data, and preparing peer-reviewed reports. All evaluations are conducted in accordance with rigorous quality assurance (QA) protocols to ensure the generation of high quality data and defensible results. NHSRC provides unbiased, third-party information supplementary to vendor- provided information that is useful to decision makers in purchasing or applying the evaluated technologies. Stakeholder involvement ensures that user needs and perspectives are incorporated into the evaluation design to produce useful performance information for each evaluated technology. In this current effort, NHSRC evaluated the performance of four liquid or foam decontamination technologies for their ability to inactivate Bacillus anthracis (Ames) spores on topsoil representative of outdoor soil surfaces. These dccontaminants were selected for testing based on existing information or data indicating potential sporicidal efficacy on soil surfaces. Such information or data could include EPA registration as a stcrilant on other types of surfaces, data showing sporicidal efficacy 011 different materials or under different test conditions, or known oxidizing capacity in other applications such as soil remediation. The dccoiitaniinants tested, which were each evaluated at two different contact times on test coupons of commercially available topsoil. included the following: • pH-Aniciidcd Ultra Clorox® Germicidal bleach (diluted with certified cell-culture grade sterile filtered water (SFVV) and 5% acetic acid to obtain pH-amended solution) • Allen-Vanguard's CASCAD'" Surface Decontamination Foam (SDF) • Ecolab Inc.'s Oxonia Active* • FMC Corporation's Klozur™ activated with hydrogen peroxide (H,0;). For C ASC AD SDF and Oxonia Active, testing was performed using spray application procedures specified by the respective vendor. For pH-aiiiciided Ultra Clorox Germicidal bleach, testing was performed using spray application procedures developed by EPA and Battcllc based on likely use of these dccoiitaniinants. For Klozur, the application procedure was based on approaches typically used in soil remediation with this product, and involved mixing a solution of Klozur and an equal volume of a H,0, activating solution with the topsoil in the coupon container. The application procedures for all decoiitaiiiiiiants are included as appendices to this report. The performance of the decontamination technologies was evaluated in terms of their quantitative decontamination efficacy, i.e., the log reduction in viable spores tliat resulted from use of the decontaiiiiiiaiit. ------- 2 ------- 2.0 Technology Description Tabic 2-1 describes the four decontamination technologies tested, and lists the contact times and number of applications used in testing. The information on product composition in Table 2-1 is based on vendor- provided information and was not confirmed in this evaluation. Detailed technology descriptions and the application procedures used arc included as Appendices A to D. Note that Ultra Clorox Germicidal bleach is registered as a disinfectant, but the pH-amended solution is not. Table 2-1. Technology Information Product Vendor General Description/ Active Ingredients Components EPA Registration" Contact Time1' (No. of Applications) Ultra Clorox Germicidal Bleach Clorox Professional Products Co. Sodium hypochlorite, hypochlorous acid Sodium hypochlorite 6.15%>, sodium hydroxide <1%> (diluted with SFW, and pH-amended by Battelle by adding acetic acid 5%)c 67619-8 (disinfectant) 60 min (4) 120 min (8) CASCAD Allen- SDF Vanguard (Reagents prior to dissolution.) GCE- 2000 Surfactant: Sodium myristyl sulfate 10-30%, sodium (CM_16) olefin sulfonate 10-30%, ethanol denatured 3-9%, alcohols (C,„ J 5-10%, sodium sulfate 3-7%, v 10-16' ' ' Hypochlorite, sodium xylene sulfonate 1-5%, proprietary hypochlorous mixture of sodium and ammonium salts acid along with co-solvent >9%; GPA-2100 Dccontaminant: dichloro-isocyanuric acid, sodium salt 70-100%o; GPB-2100 Buffer: sodium tetraborate 10-30%, sodium hydroxide 1-5%, sodium carbonate 40-65%. None 60 min (2) 120 min (4) Oxonia Active Ecolab Inc. Peroxide/ peroxy acetic acid Hydrogen peroxide 27.5%, peroxyacetic acid 5.8%) in aqueous solution. 1677-129 (sterilant, disinfectant, sanitizer) 60 min (6) 120 min (12) Klozur Persulfate Sodium persulfate (Na2S2Og) >99% purity FMC (activated (used as a 12%) (0.5 molar) aqueous Corporation with hydrogen solution, activated with hydrogen peroxide peroxide) 8%> solution)11 None 24 hr(6) 48 hr(6) Registered with the EPA Office of Pesticide Programs (OPP). Registration indicates EPA/OPP has evaluated the antimicrobial pesticide to show its effectiveness and that the pesticide will not have unreasonable adverse effects on humans, the environment, and non-target species, and EPA/OPP has issued a registration or license for use in the United States. Note: None of these products is registered for use against B. anthracis. Min = minutes, hr = hours; number of applications used in the indicated contact time shown in parentheses. Using procedure recommended by stakeholders, 5% acetic acid was added to the bleach to obtain a pH-amended bleach solution. The solution was prepared using 9.4 parts SFW, 1 part Ultra Clorox Germicidal bleach, and 1 part 5% glacial acetic acid to yield a solution having a pH of 6.36 and a total chlorine content of approximately 6,200 parts per million Equal volumes of 12% by weight (i.e., 0.5 molar) sodium persulfate and 8% by weight hydrogen peroxide solutions were applied to test coupons, resulting in a molar ratio of 5 to 1 (hydrogen peroxide to persulfate), typical of use in soil remediation. 3 ------- Below arc brief descriptions of the form and preparation instructions of the decontamination technologies. Greater detail on product composition, preparation, and application procedures is provided in Appendices A to D. • pH- Amcnded Ultra Clorox Germicidal bleach - Ultra Clorox Germicidal bleach was purchased in a one gallon container from a local retail store. The pH-a mended solution was prepared by mixing 9.4 parts SFVV, 1 part Ultra Clorox Germicidal bleach, and 1 part 5% glacial acetic acid. The diluted, pH- adjustcd final solution was applied using a hand- pressurized portable garden sprayer. • CASCAD SDF - One CASCAD solution was prepared by diluting 31.2 g of GPA-2100 (decontaminant) to 300 mL with SFVV, and the other solution was made by diluting 7.2 g of GPB-2100 (buffer) and 18 mL of GCE-2000 (surfactant) to 300 mL with SFVV. The application process used a dual spray bottle designed by the vendor to deliver equal portions of the two solutions through a single spray nozzle, and equipped with a dilluser mesh to produce the foam. • Oxonia Active - A decontaminant solution containing 5,000 parts per million (ppm) peroxyacetic acid was prepared fresh daily by diluting 76 mL of Oxonia Active to 1 L with SFVV. The diluted solution was applied using a hand- pressurized portable garden sprayer. • Klozur - Klozur is a white crystalline solid consisting of >99% pure sodium persulfate. A solution of 12% sodium persulfate was prepared by dissolving 12 grams of Klo/ur in SFVV and diluting to 100 mL; this solution was 0.5 molar (M) in sodium persulfate. Each application of the Klo/ur solution to a topsoil coupon consisted of mixing 1 mL of 0.5M persulfate solution with the topsoil. followed immediately by addition and mixing of 1 ml of 8% H ,0; solution. The vendor of Klo/ur indicates that the H ,0, activates formation of highly reactive sulfate radicals (SO, •). Equal volumes of the persulfate and H ,0, solutions resulted in a persulfatc/H;0; molar ratio of 5 to 1. a typical ratio recommended for the use of Klo/ur in soil remediation. ------- 3.0 Summary of Test Procedures Test procedures were performed in accordance with the peer-reviewed tcst/QA plan and arc briefly summarized here. 3.1 Preparation and Analysis of Test Coupons The test soil was Garde nscape* topsoil. batch number PY1A0597, purchased from a national chain honic- and-garden store. This topsoil had a moisture content of approximately 29%, and an organic content of approximately 6% on a dry weight basis, as determined by analysis in a commercial laboratory using a standard American Society for Testing and Materials (ASTM) method1 Most test coupons consisted of approximately 7 grams of unconipacted topsoil in a Parafilm®-lined 3.5 cm diameter 1 cm deep circular glass Petri dish. For tests that involved more than two applications of the dccontaminant. the same mass of topsoil was placed in a Parafilni-lincd 3.5 cm diameter • 3.4 cm deep circular Teflon beaker. That larger container was needed to capture the dccontaminant from the multiple applications. An amendment to the tcst/QA plan was prepared, reviewed, and approved for this change in the form of the coupon container. The Bacillus anthracis (Ames) spores used for this testing were prepared from a qualified stock of the Ames strain at the Battclle Biomedical Research Center (BBRC). All spore lots were subject to a stringent characterization and qualification process, required by Battclle"s standard operating procedure for spore production. Specifically, all spore lots were charactcri/cd prior to use by observation of colony morphology, direct microscopic observation of spore morphology and si/c. and determination of percent rcfractivity and percent encapsulation. In addition, the number of viable spores were determined by colony count and expressed as colony forming units per milliliter (CFU/mL). (Theoretically, once plated onto bacterial growth media, each viable spore germinates and yields one CFU.) Variations in the expected colony phenotypes were recorded. Endotoxin concentration of each spore preparation was determined by the Limulus Amcocytc Lysatc assay. Genomic DNA was extracted from the spores and DNA fingerprinting was done to confirm the genotype. The virulence of the spore lot was measured by challenging guinea pigs intradcrnially with a dilution scries of spore suspensions, and virulence was expressed as the intradermal median lethal dose. In addition, testing was conducted for robustness of the spores via HQ resistance. The stock spore suspension was prepared in SFVV at an approximate concentration of 1 x 109 spores/mL and stored by refrigeration at 4 °C. B. anthracis fAmes) spores were inoculated onto test coupons in an appropriate biosafety cabinet (BSC-II or -III) according to established Battclle procedures. Inoculated coupons were prepared fresh for each day of experimental work, by placing coupons in the BSC and inoculating at approximately 1 x 10s spores per coupon. This inoculation was accomplished by dispensing a 100- pL aliquot of the spore stock suspension (approximately 1 x 109 spores/mL) using a niicropipctte as 10 droplets (each of 10 pL volume) across the surface of the coupon. This approach provided more uniform distribution of spores across the coupon surface than would be obtained through a single drop of the suspension. After inoculation, the coupons remained undisturbed overnight in the BSC to dry. Blank (uninoculatcd) topsoil coupons were held in a separate cabinet from the spiked coupons, to avoid contamination of the blanks with spores during the drying period. On the day following spore inoculation, coupons intended for decontamination (including blanks) were transferred into a glove box (test chamber) where the decontamination technology was applied using the apparatus and application conditions specified in Appendices A to D of this report. For pH-anicndcd Ultra Clorox bleach, CASCAD SDF, and Oxonia Active, application was done by spraying the dccontaniinant onto the test coupons multiple times. The decontamination spray distance of 30 cm (12 inches), humidity (< 70% relative humidity (RH)). and temperature (20 to 25 °C) were the same for all spray applications. For C ASC AD SDF and Oxonia Active the amount of dccontaniinant. contact time, spray pressure, application and reapplication procedures, etc., were as specified by the respective vendor. For pH-anicndcd Ultra Clorox Germicidal bleach, these parameters were chosen by EPA based on common use of tliese products and reasonable application procedures for small-scale evaluation. Oxonia Active and pH-amended Ultra Clorox Germicidal bleach were both applied using the same type of commercial hand-pressuri/cd garden sprayer (1.5 L (51 oz.) GardcnPlus. Part No. 0036943, LG Sourcing, Inc.. Wilkcsboro. NC) equipped with a pressure gauge (Ashcroft 9795T117, General Purpose 0-15 pounds per square inch (psi), Grade B (Certified accuracy ± 2% at mid-scale)). C ASC AD SDF was applied using a vendor-supplied dual-compartment 5 ------- spray bottle with a mesh diffuser to create the foam. In testing of both pH-amended Ultra Clorox Germicidal bleach and Oxonia Active with a 120-minute contact time, the additional step was taken of mixing the applied dccontaniinant with the topsoil after each application using a glass stirring rod. An amendment to the test/ QA plan was prepared, reviewed, and approved for this addition to the test procedure for this decontaminant. For testing of Klozur, the 0.5 M pcrsulfate solution and 8% H;0, activating solution were poured as liquids (not sprayed) in 1 mL amounts directly onto each topsoil coupon, and mixed with the topsoil after each application using a 10 cm long glass stirring rod. This approach, and the concentrations and applied volumes of the two solutions, were chosen by EPA to follow the vendor's recommendations for use of the product in soil remediation Deposition tests were conducted before any testing with pH-a mended Ultra Clorox Germicidal bleach. CASCAD SDF, and Oxonia Active, using topsoil coupons that had not been inoculated with spores. In these tests the decontaminant was applied to three pre-weighed test coupons exactly as specified (i.e., according to the respective Appendix A, B, or C), and the mass of decontaminant applied on each coupon was determined. The average deposited mass of decontaminant was then used in neutrali/ation trials, to determine the amount of neutralizing agent needed to stop the action of the decontaminant after the prescribed contact time. No deposition test was conducted for Klo/ur. because that decontaminant was added volunictricallv to the topsoil rather than spray-applied. The neutrali/ation trials were designed to determine the required concentration of a neutralizing chemical chosen (or recommended by the vendor) to stop the action of the decontaminant being tested after the prescribed contact time. The required concentration of neutrali/cr was determined in trial runs for each contact time for each decontaminant tested. In each of those trial runs a range of neutrali/cr concentrations was tried, to determine the concentration that most effectively stopped the action of the decontaminant (as indicated by the maximum recovery of viable spores in simulated coupon extracts). An amount of topsoil equivalent to a test coupon was included in each control sample and each test sample containing neutrali/cr in each trial run. The results of those neutrali/ation trials arc shown in the respective results chapters (Cliaptcrs 5 to 8). Following decontamination, the topsoil from each coupon (along with any associated pooled dccontaniinant) was transferred aseptically to a sterile 50mL conical vial containing 10 mL of extraction solution. All extraction solutions consisted primarily of sterile phosphate-buffered saline (PBS) solution with Triton X-100 surfactant (i.e., 99.9% PBS solution. 0.1% Triton X-100), and the appropriate concentration of the neutrali/cr. The topsoil from each coupon was then extracted by agitation of the 50 mL vial on an orbital shaker for 15 minutes at approximately 200 revolutions per minute (rpm) at room temperature. Each glass stirring rod used to mix topsoil and applied dccontaniinant was extracted in the 50 mL vial along with the topsoil with which it was used. Following extraction 1 mL of the topsoil extract was removed, and a scries of dilutions through 10 "were prepared in SFVV. An aliquot (0.1 mL) of the undiluted extract and each serial dilution was then spread plated onto tryptic soy agar plates and incubated overnight at 35 to 37 °C. Plates were enumerated within 18 to 24 hours of plating. Theoretically, once plated onto the growth medium, each recovered viable spore germinates and yields one colony forming unit (CFTJ). The number of CFU/mL was determined by multiplying the average number of colonics per plate by the reciprocal of the dilution, and accounting for the 0.1 mL volume of extract or dilution that was plated. The use of topsoil as a test coupon required development of techniques to assure adequate recovery of inoculated B. anthracis spores, and the absence of interference from native soil microorganisms in counting of recovered spores. The topsoil used in testing was not stcrili/cd before use. A heat shock procedure was found to niininii/c interference by native microorganisms, and was used on all topsoil coupons. Specifically, inoculated or blank topsoil was extracted in the PBS/ Triton X-100 solution, and the recovered supernatant was heat shocked in a water bath at 65 °C for one hour before being serially diluted and plated. Topsoil samples inoculated with B. anthracis spores all showed the presence of a single homogeneous species, with all colonics of uniform si/c and morphologically distinctive for B. anthracis. Blank topsoil samples showed growth of colonics of other, native. Bacillus species, which were not seen with the inoculated topsoil samples. Consequently, although topsoil blanks showed some growth, that growth did not occur with extracts of inoculated topsoil. so no interference existed in terms of counting recovered spores. The mechanism by which growth of native Bacillus is suppressed in the extracts of inoculated topsoil was not investigated, but may involve monopolization of nutrients by the large numbers of inoculated spores. By this procedure, the recovery of B. anthracis (Ames) spores inoculated onto topsoil was found to be approximately 50%. The heat shock procedure for use of topsoil differed from the procedures used previously with other materials and stated in the tcst/QA plan; an appropriate amendment to the plan was prepared and approved before any testing with topsoil coupons was conducted. 6 ------- Before further decontamination tests, the test chamber was cleaned using the vendor-supplied method for neutralizing the decontamination reagent (see the appendices to this report). If no instructions for neutralization were provided, the test chamber was cleaned following procedures established under the BBRC Facility Safety Plan. Laboratory blanks controlled for sterility, and procedural blanks controlled for viable spores inadvertently introduced to test coupons. The procedural blanks were inoculated with an equivalent amount of 0.1 niL of "stock suspension" that did not contain the biological agent. To be considered acceptable for quantitative efficacy determination, extracts of laboratory or procedural blanks were to contain no CFU. The mean percent spore recovery was calculated using results from positive control coupons (inoculated, not decontaminated (sprayed with SFVV instead of the decontaminant)). by means of the following equation: Mean % Recovery = [Mean CFLWCFU * 100 (1) where Mean CFU is the mean number of CFU pc recovered from five replicate positive control coupons. and CFU is the number of CFU inoculated onto spike each of those coupons. The value of CFU is known A spike from enumeration of the stock spore suspension. Spore recovery from positive control coupons was calculated for B. anthracis in each decontaminant test, and the results arc included in Chapters 5 through 8. 3.2 Decontamination Efficacy The quantitative performance or efficacy of the decontamination technology was assessed by determining the number of viable organisms remaining on each test coupon, and in any decontaminant captured with the coupon, after decontamination. These data were compared with the number of viable organisms extracted from the positive control coupons sprayed with SFVV, which was the matrix for the spore suspension used to inoculate the test coupons. The number of colony-forming units (CFU) of B. anthracis m extracts of test and positive control coupons was determined to calculate efficacy of the decontaminant. Efficacy is defined as the extent (as log10 reduction) to which viable spores extracted from test coupons after decontamination were less numerous than the viable spores extracted from positive control coupons subjected only to an inert SFVV spray, at the same temperature and contact time as the decontaminant application. First, the logarithm of the CFU count value from each coupon extract was determined, and then the mean of those logarithm values was determined for each set of control and associated test coupons, respectively. Efficacy of a decontaminant for a test organism on topsoil was calculated as the difference between those mean log values, i.e.: Efficacy = (log10 CFUc, ) - (log10 CFUtj ) (2) where log10 CFUc.refers to the j individual logarithm values obtained from the positive control coupons and log10 CFUt refers to the j individual logarithm values obtained from the corresponding test coupons, and the ovcrbar designates a mean value. In tests conducted under this plan, there were five control and five corresponding test coupons (i.e., j = 5). In the case where no CFUs were found in a coupon extract, a CFU count of 1 was assigned, resulting in a log CFU of zero for that coupon. The variances (i.e., the square of the standard deviation (SD)) of the log10 CFC/c.andlog10CFC//.values were also calculated for both the control and test coupons (i.e., SD2c. and SD2tp, and were used to calculate the pooled standard error (SE) for the efficacy value calculated in Equation 2, as follows: SE-- SD'C: SD t; \ 5 5 (3) where the number 5 again represents the number j of coupons in both the control and test data sets. Thus each efficacy result is reported as a log reduction value with an associated SE value. The significance of differences in efficacy was assessed based on the 95% confidence interval of each efficacy result. The 95% confidence interval (CI) is: 95% CI = Efficacy ± (1.96 x SE) (4) Differences in efficacy were judged to be significant if the 95% CIs of the two efficacy results did not overlap. The efficacy results arc presented in a series of tables in Chapters 5 through 8 for each decontaminant. technology. ------- 8 ------- 4.0 Quality Assurance/Quality Control Quality assurance/quality control (QC) procedures were performed in accordance with the test/QA plan for this evaluation, except as noted below. QA/QC procedures are summarized below. 4.1 Equipment Calibration All equipment (e.g., pipettes, incubators, biological safety cabinets) and monitoring devices (e.g., temperature, RH) used at the time of evaluation were verified as being certified, calibrated, or validated. 4.2 QC Results Quality control efforts conducted during decontaminant testing included positive control coupons (inoculated, not decontaminated), procedural blanks (not inoculated, decontaminated), laboratory blanks (not inoculated, not decontaminated), and spike control samples (analysis of the stock spore suspension). The results for these QC samples in each decontaminant evaluation are included in the results chapter for each respective decontaminant (see Chapters 5 through 8). One QC issue regarding spore inoculation was addressed during testing, and is noted in Section 4.4. 4.3 Audits 4.3.1 Performance Evaluation Audit No performance evaluation audit was performed for B. anthracis (Ames) because a quantitative standard for such a biological material docs not exist. 4.3.2 Technical Systems Audit Battelle QA staff conducted a technical systems audit (TSA) at the BBRC on November 10, 2009 during testing of Oxonia Active to ensure tliat the evaluation was being conducted in accordance with the test/QA plan. In the TSA, test procedures were compared to those specified in the test/QA plan, and data acquisition and handling procedures were reviewed. Observations and findings from the TSA were documented and submitted to the Battelle Task Order Leader for response. No adverse findings resulted from the TSA. TSA records were permanently stored with the NHSRC QA Manager. 4.3.3 Data Quality Audit At least 10% of all test data acquired during the evaluation were audited. A Battelle QA auditor traced the data from the initial acquisition, through reduction and statistical analysis, to final reporting to ensure the integrity of the reported results. All calculations performed on the data undergoing the audit were checked. 4.4 Test/QA Plan Amendments and Deviations One amendment to the test/QA plan was prepared, reviewed, approved, and distributed to all parties involved in this evaluation. That amendment implemented both the use of the taller Teflon container for tests with multiple applications of decontaminant. and the use of a glass stirring rod to mix the topsoil and applied decontaniinant during testing. The TSA cited in Section 4.3.2 showed tliat all test procedures followed the test/QA plan, i.e., no deviations were recorded as a result of that TSA. A deviation was prepared, approved, and placed in the evaluation file regarding acceptance of spore inoculation counts outside the target range of 1 x 107coupon (± 25%) in the testing of Ultra Clorox Germicidal bleach (60 minute test) and Klozur (24 hour test). These occurrences arc noted in Sections 5.1 and 8.1, respectively. 4.5 QA/QC Reporting Each audit was documented, and the results of the audits were submitted to the EPA (i.e., to the NHSRC QA Manager and the Task Order Project Officer (TOPO)). 4.6 Data Review Records and data generated in the evaluation received a QC/technical review before they were utilized in calculating or evaluating results and prior to incorporation in reports. All data were recorded by Battelle staff. The person performing the QC/technical review was involved in the experiments and added his/ her initials and the date to a hard copy of the record being review ed. This hard copy was returned to the Battelle staff member who stored the record. ------- 10 ------- 5.0 pH-Amended Ultra Clorox Germicidal Bleach Test Results 5.1 QC Results In testing of pH-amended Ultra Clorox Germicidal bleach with B. anthracis, percent recoveries of inoculated spores from the positive control coupons were 88.6% and 108% in the 60-minute and 120-minute tests, respectively. These percent recovery values were well within the acceptable range of 1 to 150% stated in the test/Q A plan. All procedural and laboratory blanks met the criterion of no observed CFUs morphologically characteristic of B. anthracis (Ames), although other (native) organisms were found on some blank coupons. Spike control samples were taken from the spore suspension on each day of testing and serially diluted, nutrient plated, and counted to establish the spore density used to inoculate the coupons. This process takes approximately 24 hours, so spore density is known after completion of each day's testing. The target criterion is a spore suspension density of 1 x 109/mL (± 25%), leading to an inoculation of 1 x 10s spores (± 25%) on each test coupon. The actual inoculation values for B. anthracis testing were 6.97 x 107 and 8.13 x 107 CFU/coupon, respectively, on the two days of testing. Thus on the first test day the coupons received a spore inoculation that was slightly low relative to the target criterion. In light of the high spore recoveries and low efficacy observed, testing from that day was not repeated. However, a deviation from the test/QA plan documenting the acceptance of this low inoculation value was prepared, approved, and retained in the project files. 5.2 Decontamination Efficacy The quantitative efficacy results for pH-amended Ultra Clorox Germicidal bleach at the two contact times of 60 and 120 minutes are presented in Table 5-1. The decontamination efficacy of pH-amended Ultra Clorox Germicidal bleach on topsoil was 0.03 log reduction with the 60-minute contact time (four applications) and 0.94 log reduction with the 120-minute contact time (eight applications, with mixing of the topsoil and applied dccontaminant). The latter efficacy result is statistically significantly greater than the former, indicating that the additional applications, longer contact time, and/or mixing with topsoil improved the effectiveness of inactivation. However, even with eight applications and mixing of the dccontaminant and topsoil. the efficacy of Ultra Clorox Germicidal bleach was less than 1 log reduction. Table 5-1. Inactivation of Bacillus anthracis Ames Spores on Topsoil" - pH-Amended Ultra Clorov Germicidal Bleach Contact Time (Number of Applications) Inoculum (CFU) Mean of Logs of Observed CFU ±SD Mean % Recovery ±SD Decontamination Efficacy ± CI 60 Minutes (4) Positive Controls'5 6.97 x 107 7.77 ± 0.13 88.6 ±23.0 - Test Coupons0 6.97 x 107 7.74 ±0.12 81.6 ± 26.3 0.03 ±0.15 Laboratory Blankd'f 0 0 0 - Procedural Blanke'f 0 0 0 - 120 Minutes (8, stirred) Positive Controls'3 8.13 x 107 7.94 ±0.08 108 ±18 - Test Coupons0 8.13 x 107 6.99 ±0.09 12.3 ±2.3 0.94± 0.10 Laboratory Blankd,f 0 0 0 - Procedural Blanke,f 0 0 0 - a Data are expressed as mean (± SD) of the logs of total number of spores (CFU) observed on individual coupons, mean percent recovery, and decontamination efficacy (log reduction). CI = confidence interval (± 1.96 x SE) b Inoculated, not decontaminated coupon (sprayed with SFW). c Inoculated, decontaminated coupon. d Laboratory Blank = not inoculated, not decontaminated coupon, e Procedural Blank = not inoculated, decontaminated coupon. f Endogenous organisms were found in topsoil blanks; no organisms other than B. anthracis Ames were found on inoculated coupons. Not Applicable. 5.3 Other Factors 5.3.1 Operator Control The pH-amended Ultra Clorox Germicidal bleach was prepared according to the procedure described in Appendix A, by mixing 9.4 parts SFW, 1 part Ultra Clorox Germicidal bleach, and 1 part 5% acetic acid. The bleach used was obtained through a retail purchase, and the bottle was unopened until the first day of use. The actual resulting solution used for testing with B. anthracis had a pH of 6.36 and a total chlorine content of approximately 6,200 ppm. The pH-amended Ultra Clorox Germicidal bleach was freshly prepared prior to each testing day (i.e., the preparation was assigned a one day shelf-life and excess was discarded at the end of the day). All trials were conducted at ambient conditions inside a climate-controlled laboratory. The temperature inside the testing chamber was equilibrated to the ambient laboratory temperature of approximately 22 (± 1) °C. 11 ------- The RH was monitored with a hygrometer traceable to the National Institute of Standards and Technology (NIST). The RH in the test chamber was controlled as necessary by an automatic dchumidifier set to maintain RH below 70%. That system never activated during decontamination withpH-amended Ultra Clorox Germicidal bleach, and therefore the testing chamber RH was always less than 70% during testing. 5.3.2 Technology Spray Deposition The pH-amended Ultra Clorox Germicidal bleach was applied according to the procedure in Appendix A. The pH-amended Ultra Clorox Germicidal bleach was applied 12 inches from the topsoil coupons until the topsoil appeared saturated with liquid. The same type of handheld garden sprayer was used to apply the control application (SFVV) and the pH-amended Ultra Clorox Germicidal bleach. Each sprayer was slightly modified to accommodate a pressure gauge to ensure that the spray was applied using 4 to 6 psi pressure. After the prescribed contact time, each topsoil coupon and the collected decontaminant. were placed in a 50 mL conical vial for extraction. To assess pH-amended Ultra Clorox Germicidal bleach deposition, triplicate topsoil coupons were weighed, and these values were recorded. Then the triplicate coupons were sprayed with pH-amended Ultra Clorox Germicidal bleach according to the test procedure in Appendix A. The pre-application weights were then subtracted from the post-application weights, which included the weight of decontaminant captured with each coupon. This process was conducted separately for the 60-minute and 120-ininute application procedures ( Appendix A) which required four and eight applications of pH-amended Ultra Clorox Germicidal bleach, respectively. The mass of Ultra Clorox Germicidal bleach deposited on topsoil coupons in the 60-minute test (4 applications) averaged 2.60 g, and in the 120-minute test (8 applications) averaged 3.55 g. The density of the diluted bleach deposited on the test coupons was not measured directly, but was estimated to be approximately 1.0 g/mL. Based on that density, volumes of 2.60 and 3.55 niL were then used in trials to determine the amount of sodium thiosulfate (STS) needed to neutralize the Ultra Clorox Germicidal bleach (Section 5.3.3). 5.3.3 Neutralization Methodology Neutrali/ation of the pH-amended Ultra Clorox Germicidal bleach was achieved with STS. The results of the neutrali/ation trials for B. anthracis with the 60-minute and 120-minute applied volumes of pH- anicnded Ultra Clorox Germicidal bleach are shown in Tables 5-2 and 5-3, respectively. Based on these neutralization results, a concentration of 1.0% STS in the extraction solution was chosen for neutrali/ation of the pH-amended Ultra Clorox Germicidal bleach in the 60-minute test, and a concentration of 1.5% STS was chosen for neutrali/ation in the 120-minute test. Table 5-2. Neutralization Testing with Bacillus anthracis (Ames) Spores on Topsoil for pH-Amended Ultra Clorox Germicidal Bleach (60 Minute Contact Time, Volume Equal to 4 Applications) Treatment Inoculum (CFU) Total Observed CFU % of Control pH-amended Ultra Clorox Germicidal bleach + Spores8 9.00 x 107 0 0 pH-amended Ultra Clorox Germicidal bleach + PBS + Triton X-100 + Spores3-1' 9.00 x 107 0 0 PBS + Triton X-100 + Spores (Control)1' 9.00 x 107 9.00 x 107 - pH-amended Ultra Clorox Germicidal bleach + PBS + Triton X-100 + 0.5% STS + Spores3-1' 9.00 x 107 7.93 x 107 88.2 pH-amended Ultra Clorox Germicidal bleach + PBS + Triton X-100 + 1.0% STS + Spores3-1' 9.00 x 107 9.10 x 107 101.1 pH-amended Ultra Clorox Germicidal bleach + PBS + Triton X-100 + 1.5% STS+ Spores3-1' 9.00 x 107 7.63 x 107 84.7 a pH-amended Ultra Clorox Germicidal bleach volume of 2.60 mL corresponds to mean gravimetric deposition on topsoil coupons, b 10 mL volume of PBS includes 0.1% of Triton X-100 surfactant and indicated % of STS; total volume for all samples with pH-amended Ultra Clorox Germicidal bleach = 12.60 mL (10 mL PBS/Triton/STS + 2.60 mL pH- amended Ultra Clorox Germicidal bleach). Not Applicable. 12 ------- Table 5-3. Neutralization Testing with Bacillus anthracis (Ames) Spores on Topsoil for pH-Amended Ultra Clorox Germicidal Bleach (120-Minute Contact Time, Volume Equal to 8 Applications) Treatment Inoculum (CFU) Total Observed CFU % of Control pH-amended Ultra Clorox Germicidal bleach + Spores1 8.57 x 107 0 0 pH-amended Ultra Clorox Germicidal bleach + PBS + Triton X-100 + Sporesa'b 8.57 x 107 0 0 pH-amended Ultra Clorox Germicidal bleach + Triton X-100 + Spores (Control)1' 8.57 x 107 7.91 x 107 - pH-amended Ultra Clorox Germicidal bleach + PBS + Triton X-100 + 1.0% STS + Sporesa'b 8.57 x 107 7.65 x 107 96.7 pH-amended Ultra Clorox Germicidal bleach + PBS + Triton X-100 + 1.5% STS+ Sporesab 8.57 x 107 8.73 x 107 110.4 pH-amended Ultra Clorox Germicidal bleach + PBS + Triton X-100 + 2.0% STS + Sporesab 8.57 x 107 7.93 x 107 100.3 a pH-amended Ultra Clorox Germicidal bleach volume of 3.55 mL corresponds to mean gravimetric deposition on topsoil coupons, b lOmL volume of PBS includes 0.1% of Triton X-100 surfactant and indicated % of STS; total volume for all samples with pH-amended Ultra Clorox Germicidal bleach = 13.55 mL (10 mL PBS/Triton/ STS + 3.55 mL pH-amended Ultra Clorox Germicidal bleach). Not Applicable. 13 ------- 14 ------- 6.0 CASCAD SDF (Allen-Vanguard) Test Results 6.1 QC Results In testing of CASCAD SDF with B. anthracis, percent recoveries of inoculated spores from the positive control coupons were 80.1% and 106% in the 60-minute and 120-minute tests, respectively. These percent recovery values were well within the acceptable range of 1 to 150% stated in the test/QA plan. All procedural and laboratory blanks met the criterion of no observed CFUs morphologically characteristic of B. anthracis (Ames), although other (native) organisms were found on some blank coupons. Spike control samples were taken from the spore suspension on each day of testing, and serially diluted, nutrient plated, and counted to establish the spore density used to inoculate the coupons. This process takes approximately 24 hours, so the spore density is known after completion of each day's testing. The target criterion is to maintain a spore suspension density of 1 x 109/mL (± 25%), leading to an inoculation of 1 x 10s spores (± 25%) on each test coupon. The actual inoculation values for two days of B. anthracis testing were 7.80 x 107 CFU/coupon and 8.40 x 107 CFU/oupon, within the ±25% tolerance of the 1 x l()7coupon target. 6.2 Decontamination Efficacy The quantitative efficacy results for CASCAD SDF at the two contact times of 60 minutes (two applications) and 120 minutes (four applications) are presented in Table 6-1. The decontamination efficacy of C ASC AD SDF on topsoil was 0.59 log reduction with the 60-minute contact time (two applications) and 1.13 log reduction with the 120-minute contact time (four applications). The 120-minute efficacy result is statistically significantly greater than the 60-minute result, indicating that the additional applications of C ASC AD SDF and/or the longer contact time improved the effectiveness of inactivation. However, even with four applications and the 120-minute contact time the efficacy of CASCAD SDF was only slightly greater than 1 log reduction. 6.3 Other Factors 6.3.1 Operator Control On each day of testing, the two components of Allen- Vanguard's CASCAD SDF were prepared according to the vendor's instructions in Appendix B. The spray nozzle was then placed onto the dual-chamber bottle, in which each chamber of the bottle contained one of the two C ASC AD SDF reagent solutions. Prior to each application, the CASCAD SDF spray nozzle was primed by repeatedly spraying into an absorbent cloth to clear any air bubbles that may have formed between applications. After each application, the spray nozzle was removed from the bottle and any residual C ASC AD SDF was removed by repeated pulls on the trigger of the Table 6-1. Inactivation of BaciUm anthracis Ames Spores on Topsoil" - CASCAD SDF Contact Time (Number of Applications) Inoculum (CFU) Mean of Logs of Observed CFU ±SD Mean % Recovery ±SD Decontamination Efficacy ± CI 60 Minutes (2) Positive Controls1" Test Coupons' Laboratory Blankd f Procedural Blankef 7.80 x 107 7.80 x 107 0 0 7.79 ± 0.04 7.21 ±0.02 0 0 80.1 ±6.8 20.6 ±0.9 0 0 0.59 ±0.04 120 Minutes (4) Positive Controls'1 Test Coupons' Laboratory Blankdf Procedural Blankef 8.40 x 107 8.40 x 107 0 0 7.95 ±0.06 6.81 ±0.12 0 0 106.3 ± 14.7 8.0 ±2.2 0 0 1.13 ± 0.12 a Data are expressed as mean (± SD) of the logs of total number of spores (CFU) observed on individual coupons, mean percent recovery, and decontamination efficacy (log reduction). CI = confidence interval (± 1.96 x SE). b Inoculated, not decontaminated coupon (sprayed with SFW). c Inoculated, decontaminated coupon. d Laboratory Blank = not inoculated, not decontaminated coupon, e Procedural Blank = not inoculated, decontaminated coupon. Endogenous organisms were found in topsoil blanks; no organisms other than B. anthracis Ames were found on inoculated coupons. f Not Applicable. ------- spray nozzle. The spray nozzle was then placed onto a dual chamber bottle that contained only SFVV so as to completely clean out the spray nozzle until its next use. All tests were conducted under ambient conditions inside a climate-controlled laboratory. The temperature inside the test chamber was equilibrated to the ambient laboratory temperature of approximately 22 (± 1) °C. The RH inside the test chamber was monitored with a NIST-traceable hygrometer. Whenever the RH reached 70%, an automatic dehuinidification system attached to the testing chamber was actuated until the RH dropped below 70%. The dchumidifier did not actuate during the prescribed contact times with the CASCAD SDF. Therefore, the testing chamber RH was always less than 70% during decontamination with CASCAD SDF. 6.3.2 Technology Spray Deposition Allen-Vanguard's C ASC AD SDF was applied according to the procedure included as Appendix B of this report. C ASC AD SDF was applied from a distance of 12 inches from the topsoil coupons, with the aim of fully covering the topsoil coupon with approximately a 3/8 inch layer of foam. After the prescribed contact time, each topsoil coupon and the collected decontaminant. were placed in a 50 mL conical vial for extraction. To assess CASCAD SDF deposition, triplicate topsoil coupons were weighed, and these values were recorded. Then the triplicate coupons were spray ed with C ASC AD SDF according to the test procedure in Appendix B. The preapplication weights were then subtracted from the post-application weights, which included the weight of decontaminant captured with each coupon. The resulting mass was used to estimate the amount of STS needed to effectively neutralize the C ASC AD SDF. This process was conducted separately for the 60-minute and 120-minute application procedures (Appendix B) which required two and four applications of C ASC AD SDF. respectively. The mass of C ASC AD SDF deposited on topsoil coupons in the 60-minute test (2 applications) averaged 2.93 g, and in the 120-minute test (4 applications) averaged 6.46 g. The density of the C ASC AD SDF deposited on the test coupons was not measured directly, but was estimated to be approximately 1.0 g/mL, based on the compositions of the two component solutions that produce the delivered foam (see Appendix B). Based on that density , volumes of 2.93 and 6.46 mL were then used in trials to determine the amount of STS needed to neutralize the C ASC AD SDF (Section 6.3.3). 6.3.3 Neutralization Methodology Neutrali/ation of C ASC AD SDF was achieved with STS. The results of the neutrali/ation trials for B. anthracis with the 60-niinute and 120-niinute application procedures arc shown in Tables 6-2 and 6-3, respectively. Based on these neutrali/ation results, a concentration of 1.5% STS in the extraction solution was chosen for neutrali/ation of CASCAD SDF in the 60-niinute test, and a concentration of 2.0% STS was chosen for neutrali/ation in the 120-niinute test. Table 6-2. Neutralization Testing with Bacillus anthracis (Ames) Spores on Topsoil for CASCAD SDF (60 Minute Contact Time, Volume Equal to 2 Applications) Treatment Inoculum (CFU) Total Observed (CFU) % of Control CASCAD SDF - y Spores1 8.69 x 107 0 0 CASCAD SDF - I- PBS - I-Triton X-10CH - Sporesab 8.69 x 107 0 0 PBS + Triton X-00 + Spores (Control) 8.69 x 107 1.06 x 10s - CASCAD SDF - I- PBS - I-Triton X-10CH - 0.5% STS H H Sporesab 8.69 x 107 3.45 x 107 32.4 CASCAD SDF - I- PBS - I- Triton X-10CH - 1.0% STS H H Sporesab 8.69 x 107 8.87 x 107 83.3 CASCAD SDF - I- PBS - I- Triton X-10CH - 1.5% STS H H Sporesab 8.69 x 107 1.00 x 10s 94.4 a CASCAD SDF volume of 2.93 mL corresponds to mean gravimetric deposition on topsoil coupons. b 10 mL volume of PBS includes 0.1% of Triton X-100 surfactant and indicated % of STS; total volume for all samples with CASCAD SDF = 12.93 mL (10 mL PBS+Triton +STS + 2.93 mL CASCAD SDF). Not Applicable. 16 ------- Table 6-3. Neutralization Testing with Bacillus anthracis (Ames) Spores on Topsoil for CASCAD SDF (120 Minute Contact Time, Volume Equal to 4 Applications) Treatment Inoculum (CFU) Total Observed (CFU) %of Control CASCAD SDF + Spores1 8.00 x 107 0 CASCAD SDF + PBS + Triton X-100 + Spores"'" 8.00 x 107 PBS + Triton X-100 + Spores (Control)" 8.00 x 107 7.81 x 107 CASCAD SDF + PBS + Triton X-100 + 1.5% STS + Spores*'" 8.00 x 107 6.87 x 107 88.0 CASCAD SDF + PBS + Triton X-100 + 2.0% STS + Spores8" 8.00 x 107 8.49 x 107 108.7 CASCAD SDF + PBS + Triton X-100 + 2.5% STS + Spores*" 8.00 x 107 7.88 x 107 101.0 CASCAD SDF + PBS + Triton X-100 + 3.0% STS + Spores8" 8.00 x 107 8.47 x 107 108.4 a CASCAD SDF volume of 6.46 mL corresponds to mean gravimetric deposition on topsoil coupons. b 10 mL volume of PBS includes 0.1% of Triton X-100 surfactant and indicated % of STS; total volume for all samples with CASCAD SDF = 16.46 mL (10 mL PBS+Triton +STS + 6.46 mL CASCAD SDF). Not Applicable. 17 ------- 18 ------- 7.0 Oxonia Active (Ecolab) Test Results 7.1 QC Results In testing of Oxonia Active with B. anthracis, percent recoveries of inoculated spores from the positive control coupons were 79.5% and 102% in the 60-minute and 120-minute tests, respectively. These percent recovery values were well within the acceptable range of 1 to 150% stated in the test/QAplan. All procedural and laboratory blanks met the criterion of no observed CFUs morphologically characteristic of B. anthracis (Ames), although other (native) organisms were found on some blank coupons. Spike control samples were taken from the spore suspension on each day of testing, and serially diluted, nutrient plated, and counted to establish the spore density used to spike the coupons. This process takes approximately 24 hours, so the spore density is known after completion of each day "s testing. The target criterion is to maintain a spore suspension density of 1 x lOVmL (± 25%), leading to a spike of 1 x 108 spores (± 25%) on each test coupon. The actual spike values for two days of B. anthracis testing were 8.23 x 107 CFU/ coupon and 9.07 x 107 CFU/coupon, well within the ±25% tolerance of the 1 x l()7coupon target. 7.2 Decontamination Efficacy The quantitative efficacy results for Oxonia Active at the two contact times of 60 and 120 minutes are presented in Table 7-1. The decontamination efficacy of Oxonia Active on topsoil was 0.58 log reduction with the 60-minute contact time (six applications) and 1.04 log reduction with the 120-minute contact time (12 applications, with mixing of the topsoil and applied decontaminant). The latter efficacy result is statistically significantly greater than the former, indicating that the additional applications, longer contact time, and/ or mixing with topsoil improved the effectiveness of inactivation. However, even with 12 applications and mixing of the decontaminant and topsoil, the efficacy of Oxonia Active was only slightly greater than 1 log reduction. 7.3 Other Factors 7.3.1 Operator Control On each day of testing, Oxonia Active was prepared Table 7-1. Inactivation of Bacillus anthracis Ames Spores on Topsoil" - Oxonia Active Contact Time Inoculum (Number of Applications) (CFU) Mean of Logs of Observed CFU ± SD Mean % Recovery ±SD Decontamination Efficacy ± CI 60 Minutes (6) Positive Controls'' Test Coupons' Laboratory Blankdf Procedural Blankef 8.23 x 107 8.23 x 107 0 0 7.81 ±0.05 7.23 ±0.21 0 0 79.51 ±8.6 23.0 ± 14.1 0 0 0.58 ± 0.19 120 Minutes (12, stirred) 7.96 ±0.05 102.1 ± 11.5 Positive Controls" 9.07 x 107 6.93 ± 0.11 9.6 ±2.4 1.04±0.10 Test Coupons' 9.07 x 107 q q Laboratory Blank4' 0 q q Procedural Blankef 0 a Data are expressed as mean (± SD) of the logs of total number of spores (CFU) observed on individual coupons, mean percent recovery, and decontamination efficacy (log reduction). CI = confidence interval (± 1.96 x SE). b Inoculated, not decontaminated coupon (sprayed with SFW). c Inoculated, decontaminated coupon. d Laboratory Blank = not inoculated, not decontaminated coupon, e Procedural Blank = not inoculated, decontaminated coupon. f Endogenous organisms were found in topsoil blanks; no organisms other than B. anthracis Ames were found on inoculated coupons. Not Applicable. 19 ------- according to the vendor's explicit instructions as stated in Appendix C. After the Oxonia Active was diluted in SFVV, the product was tested to ensure that the active component (pcroxyacetic acid) was within the range specified by the vendor. This check was done using a test kit also provided by the vendor (High Oxonia Active Test Kit 322). All such checks showed the prepared solution to be in the correct range. The diluted Oxonia Active was then transferred to a handheld garden sprayer modified with a pressure gauge to ensure that the spray was applied using 4 to 6 psi pressure. All tests were conducted at ambient conditions inside a climate-controlled laboratory. The temperature inside the test chamber was equilibrated to the ambient laboratory temperature of approximately 22 (± 1) °C. The RH inside the test chamber was monitored with a NIST-traceable hygrometer. Whenever the RH reached 70%, as it did during reapplications of the Oxonia Active, the dchuniidification system attached to the testing chamber was actuated until the RH dropped below 70%. Therefore, the testing chamber RH was always < 70% during decontamination with Oxonia Active. 7.3.2 Technology Spray Deposition Oxonia Active was applied according to the procedure included as Appendix C of this report. Oxonia Active was applied from a distance of 12 inches from the topsoil coupons. Reapplication of the Oxonia Active was made every 10 minutes. The same type of handheld garden sprayer was used to apply the control application (SFVV) and the Oxonia Active. Each sprayer was slightly modified to accommodate a pressure gauge to ensure that the spray was applied using 4 to 6 psi pressure. After the required contact time, each topsoil coupon and the collected decontaminant. were placed in a 50 mL collection vial for extraction. To assess Oxonia Active deposition, triplicate topsoil coupons were weighed, and these values were recorded. Then the triplicate coupons were sprayed with Oxonia Active according to the test procedure in Appendix C. The pre-application weights were then subtracted from the post-application weights, which included the weight of decontaminant captured with each coupon. This process was conducted separately for the 60-minute and 120-minute application procedures ( Appendix C) which required six and 12 applications of Oxonia Active, respectively. The mass of Oxonia Active deposited on topsoil coupons in the 60-minute test (6 applications) averaged 4.00 g, and in the 120-ininute test (12 applications) averaged 7.07 g. The density of the Oxonia Active deposited on the test coupons was not measured directly, but was estimated to be approximately 1.0 g/mL, based on the preparation instructions for the decontaminant (see Appendix C). Based on that density, volumes of 4.00 and 7.07 mL were then used in trials to determine the amount of STS needed to neutralize the Oxonia Active (Section 7.3.3). 7.3.3 Neutralization Methodology Neutralization of the Oxonia Active was achieved with STS. The results of the neutrali/ation trials for B. anthracis with the 60-minute and 120-minute application procedures arc shown in Tables 7-2 and 7-3, respectively. Based on these neutrali/ation results, a concentration of 3% STS in the extraction solution was chosen for neutrali/ation of Oxonia Active in the 60-minute test, and a concentration of 5% STS was chosen for neutrali/ation in the 120-niinute test. Table 7-2. Neutralization Testing with BaciUrn anthracis (Ames) Spores on Topsoil for Oxonia Active (60 Minute Contact Time, Volume Equal to 6 Applications) Treatment Inoculum (CFU) Total Observed (CFU) % of Control Oxonia Active H H Spores8 8.60 x 107 0 0 Oxonia Active H H PBS + TritonX-100 H H Sporesab 8.60 x 107 0 0 PBS + Triton X-100 + Spores (Control)11 8.60 x 107 8.95 x 107 - Oxonia Active H H PBS + Triton X-100 H h 2.0% STS H H Sporesa'b 8.60 x 107 7.61 x 107 85.0 Oxonia Active H H PBS + Triton X-100 H h 2.5% STS H H Sporesab 8.60 x 107 8.69 x 107 97.2 Oxonia Active H H PBS + Triton X-100 H h 3.0% STS H H Sporesa'b 8.60 x 107 9.35 x 107 104.5 Oxonia Active H H PBS + Triton X-100 H h 3.5% STS H H Sporesa'b 8.60 x 107 9.61 x 107 107.5 a Oxonia Active volume of 4.00 mL corresponds to mean gravimetric deposition on soil coupons. b 10 mL volume of PBS includes 0.1% of TritonX-100 surfactant and indicated % of STS; total volume for all samples with OxoniaX-100/STS + 4.00 mL Oxonia Active). Not Applicable. 20 ------- Table 7-3. Neutralization Testing with Bacillus anthracis (Ames) Spores on Topsoil for Oxonia Active (120 Minute Contact Time, Volume Equal to 12 Applications) Treatment Inoculum (CFU) Total Observed (CFU) % of Control Oxonia Active H H Spores8 8.87 x 107 0 0 Oxonia Active H H PBS + Triton X-100 H H Sporesb 8.87 x 107 0 0 PBS + Triton X-100 + Spores (Control)' 8.87 x 107 8.69 x 107 - Oxonia Active H H PBS + Triton X-100 H h 3.0% STS H - Sporesb 8.87 x 107 0 0 Oxonia Active H H PBS + Triton X-100 H h 3.5% STS H - Sporesb 8.87 x 107 0 0 Oxonia Active H H PBS + Triton X-100 H h 4.0% STS H - Sporesb 8.87 x 107 0 0 Oxonia Active H H PBS + Triton X-100 H h 4.5% STS H - Sporesb 8.87 x 107 6.39 x 107 73.5 Oxonia Active H H PBS + Triton X-100 H h 5.0% STS H - Sporesb 8.87 x 107 8.31 x 107 95.6 a Oxonia Active volume of 7.07 mL corresponds to mean gravimetric deposition on soil coupons. b 10 mL volume of PBS includes 0.1% of Triton X-100 surfactant and indicated % of STS; total volume for all samples with Oxonia Active = 17.07 mL (10 mL of PBS/ Triton X-100/STS + 7.07 mL Oxonia Active). Not Applicable. 21 ------- 22 ------- 8.0 Klozur (FMC Corporation) Test Results 8.1 QC Results In testing of Klozur with B. anthracis, percent recoveries of inoculated spores from the positive control coupons were 41% and 95% in the 24-hour and 48-hour tests, respectively. These percent recovery values were well within the acceptable range of 1 to 150% stated in the test/Q A plan. The procedural and laboratory blanks met the criterion of no observed CFUs in quantitative efficacy testing with B. anthracis (Ames). Spike control samples were taken from the spore suspension on each day of testing, and serially diluted, nutrient plated, and counted to establish the spore density used to spike the coupons. This process takes approximately 24 hours, so the spore density is known after completion of each day's testing. The target criterion is to maintain a spore suspension density of 1 x lOVmL (± 25%), leading to a spike of 1 x 10s spores (± 25%) on each test coupon. The actual spike values for the two B. anthracis tests were 6.93 x 107 CFU/ coupon and 7.53 x 107 CFU/coupon for the 24 hour and 48 hour tests, respectively. Thus in the 24 hour test the coupons received a spore inoculation that was slightly low relative to the target criterion. In light of the high spore recoveries and low efficacy observed, testing from that day was not repeated. However, a deviation from the test/Q A plan documenting the acceptance of this low inoculation value was prepared, approved, and retained in the project files. 8.2 Decontamination Efficacy The quantitative efficacy results for Klozur at the two contact times of 24 hours and 48 hours are presented in Table 8-1. The decontamination efficacy of Klozur on topsoil was 1.65 log reduction with the 24-hour contact time (six applications) and 3.50 log reduction with the 48-hour contact time (also six applications). These efficacy results are both statistically significantly higher than any efficacy value obtained with the other dccoiitaiiiinants. and are also significantly different from one another. The relatively high log reduction of 3.5 logs (compared to other dccoiitaiiiinants) achieved with Klo/ur with the 48-hour contact time may be due to the relatively large volume of combined oxidants (Klozur persulfate and H;0;) used and the extended contact time, as well as a more effective chemistry. Table 8-1. Inactivation of Bacillus anthracis Ames Spores on Topsoil" - Klozur Contact Time , . . Mean of Logsof Mean % Recovery Decontamination Inoculum (CFU) Observed CFU , (Number of Applications) ±Si) Efficacy ± CI i OlJ 24 Hours (6, stirred) Positive Controls" 6.93 x 107 7.48 ±0.16 45.9 ±19.6 Test Coupons' 6.93 x 107 5.83 ± 0.04 0.97 ±0.09 1.65 ±0.14 Laboratory Blank4' 0 0 0 - Procedural Blankef 0 0 0 - 48 Hours (6, stirred) Positive Controls" 7.53 x 107 7.85 ±0.08 95.0 ±15.7 Test Coupons' 7.53 x 107 4.35 ±0.45 0.039 ±0.022 3.50 ±0.40 Laboratory Blankd f 0 0 0 - Procedural Blankef 0 0 0 - a Data are expressed as mean (± SD) of the logs of total number of spores (CFU) observed on individual coupons, percent recovery, and decontamination efficacy (log reduction). CI = confidence interval (± 1.96 x SE). b Inoculated, not decontaminated coupon (sprayed with SFW). c Inoculated, decontaminated coupon. d Laboratory Blank = not inoculated, not decontaminated coupon, e Procedural Blank = not inoculated, decontaminated coupon. f Endogenous organisms were found in topsoil blanks; no organisms other than B. anthracis Ames were found on inoculated coupons. Not Applicable. 23 ------- 8.3 Other Factors 8.3.1 Operator Control On each day of testing, a 0.5 M Klo/ur solution was prepared according to the vendor's instructions as stated in Appendix D. The activating solution of 8% H,0, was obtained from a commercial supplier. Unlike the other decontaniinants tested. Klo/ur and the H;0, activating solution were not sprayed onto the soil coupons, but were added to each coupon directly in 1 niL aliquots. All tests were conducted at ambient conditions inside a climate-controlled laboratory. The temperature inside the test chamber was equilibrated to the ambient laboratory temperature of 22 (± 1) °C. The RH in the test chamber was monitored with a NIST-traceable hygrometer. A dehuniidification system on the test chamber was designed to actuate whenever the RH reached 70%. That system never activated during decontamination with Klo/ur. and therefore the cliamber RH was always less than 70% during testing. 8.3.2 Technology Deposition Klo/ur was applied according to the procedure included as Appendix D of this report. After the required contact time, each topsoil coupon and the collected decontaniinant were placed in a 50 niL collection vial for extraction. Deposition experiments were not needed for Klo/ur. since the Klo/ur and H,0, solutions were applied to the topsoil coupons voluinetrically. The total amount of the applied solutions was 12 niL for each of the 24-hour and 48-hour contact times (6 applications, each of 1 niL of Klo/ur solution and 1 niL of H,0, solution). This volume was used to estimate the amount of STS needed to effectively neutralize the Klozur/H,0, mixture for both contact times. 8.3.3 Neutralization Methodology Neutrali/ation of Klo/ur/H,0; was achieved with STS. The results of the neutralization trials for B. anthracis with the 24-hour and 48-hour contact times are shown in Tables 8-2 and 8-3, respectively. The neutralization of Klo/ur with STS was not as effective as the spore recoveries relative to the control were less than 20%, even with STS comprising 20% of the PBS/Triton X-100/STS extraction solution. This result may be due to the large volume of Klo/ur + H,0, solution used (i.e., 12 niL). In any case, at the maximum spore recovery conditions there was less than a 1 log loss in viable spores, leaving ample spores for determination of the efficacy of Klo/ur. Based on these neutrali/ation results, a concentration of 5% STS in the extraction solution was chosen for neutrali/ation of Klo/ur in the 24-hour test, and a concentration of 20% STS was chosen for neutrali/ation in the 48-hour test. Table 8-2. Neutralization Testing with Bacillus anthracis (Ames) Spores on Topsoil for Klozur (24 Hour Contact Time, Volume Equal to 6 Applications) Treatment Inoculum (CFU) Total Observed (CFU) % of Control Klozur + Spores8 7.87 x 107 0 Klozur + PBS + Triton X-100 + Spores8'" 7.87 x 107 PBS + Triton X-100 + Spores (Control)1' 7.87 x 107 5.60 x 107 Klozur + PBS + Triton X-100 + 2.5% STS + Spores8" 7.87 x 107 1.09 x 106 2.0 Klozur + PBS + Triton X-100 + 5% STS + Spores8 7.87 x 107 1.01 x 107 18.1 Klozur + PBS + Triton X-100 + 7.5% STS + Spores8" 7.87 x 107 x 106 6.8 a Decontaminant volume of 12.0 mL consists of 6.0 mL 0.5 M Klozur solution and 6.0 mL of 8% H202 solution. b 10 mL volume of PBS includes 0.1% of Triton X-100 surfactant and indicated % of STS; otal volume for all samples with Klozur = 22.0 mL (10 mL of PBS/Triton X-100/STS + 12.0 mL Klozur/H202). Not Applicable. 24 ------- Table 8-3. Neutralization Testing with Bacillus anthracis (Ames) Spores on Topsoil for Klozur (48 Hour Contact Time, Volume Equal to 6 Applications) Treatment Inoculum (CFU) Total Observed (CFU) % of Control Klozur + Spores1 7.53 x 107 0 0 Klozur + PBS h Triton X-100 H Spores3-1' 7.53 x 107 0 0 PBS + Triton X-100 + Spores (Control)b 7.53 x 107 5.17 x 107 - Klozur + PBS H Triton X-100 H 10.0% STS H Sporesab 7.53 x 107 7.33 x 106 14.2 Klozur + PBS H Triton X-100 H 12.5% STS H Sporesab 7.53 x 107 6.85 x 106 13.3 Klozur + PBS H Triton X-100 H 15.0% STS H H Sporesab 7.53 x 107 6.45 x 106 12.5 Klozur + PBS H Triton X-100 H 17.5% STS H Sporesab 7.53 x 107 8.00 x 106 15.5 Klozur + PBS H H Triton X-100 H 20.0% STS H H Sporesab 7.53 x 107 9.70 x 106 18.8 a Decontaminant volume of 12 mL consists of 6.0 mL 0.5 M Klozur solution and 6.0 mL of 8% H202 solution. b 10 mL volume of PBS includes 0.1% of Triton X-100 surfactant and indicated % of STS; total volume for all samples with Klozur = 22.0 mL (10 mL of PBS/Triton X-100/STS + 12.0 mL Klozur/H202). Not Applicable. ------- 26 ------- 9.0 Performance Summary 9.1 pH-Amended Ultra Clorox Germicidal Bleach Results • The quantitative efficacy of pH-amended Ultra Clorox Germicidal bleach for inactivating B. anthracis (Ames) spores on topsoil was 0.03 (± 0.15) log reduction with four applications and a 60-minute contact time, and 0.94 (± 0.10) log reduction with eight applications and a 120-minute contact time that included mixing the topsoil and decontaminant after each application. • The efficacy result with the 120-minute contact time is statistically significantly greater than the efficacy at the 60-minute contact time. 9.2 CASCAD SDF Results • The quantitative efficacy of C ASC AD SDF for inactivating B. anthracis (Ames) spores on topsoil was 0.59 (± 0.04) log reduction with two applications and a 60-minute contact time, and 1.13 (±0.12) log reduction with four applications and a 120-minute contact time. • The efficacy result with the 120-minute contact time is statistically significantly greater than the efficacy at the 60-minute contact time. 9.3 Oxonia Active Results • The quantitative efficacy of Oxonia Active for inactivating B. anthracis (Ames) spores on topsoil was 0.58 (± 0.19) log reduction with six applications and a 60-minute contact time, and 1.04 (± 0.10) log reduction with 12 applications and a 120-minute contact time that included mixing the topsoil and decontaminant after each application. • The efficacy result with the 120-minute contact time is statistically significantly greater than the efficacy at the 60-minute contact time. 9.4 Klozur Results • The quantitative efficacy of Klo/ur for inactivating B. anthracis (Ames) spores on topsoil was 1.65 (± 0.14) log reduction with six applications and a 24- hour contact time, and 3.50 (± 0.40) log reduction with six applications and a 48-hour contact time. • The efficacy results at the 24 and 48-hour contact times arc statistically significantly different from one another, and both efficacy results with Klo/ur are statistically significantly higher than any efficacy result with any other decontaminant tested. 27 ------- 28 ------- 10.0 References 1. American Society for Testing and Materials Method D2974-07a, Moisture, Ash and Organic Matter of Peat and Other Organic Soils, ASTM International, West Conshohocken, PA, 2007, DOI: 10.1520/D2974-07A, www.astm.org. 29 ------- 30 ------- Appendix A: pH-Amended Bleach Description and Application Procedure General Description For testing of efficacy against B. anthracis on soil. pH- amcndcd bleach consisted of bleach diluted in water and its pH adjusted by addition of acetic acid. Specifically. Ultra Clorox® Germicidal Bleach was used, which contains 6.15% by weight sodium hypochlorite (NaOCl) and < 1.0% sodium hydroxide (NaOH) in aqueous solution. This product is strongly basic, having a pH between 11-12, and has a density of 1.08 to 1.11 g/mL. The pH adjustment is achieved by addition of 5% acetic acid. The recipe for preparation of pH-amended bleach for use as a decontaminant is as follows: • Prepare 5% acetic acid solution by diluting 50 niL of glacial acetic acid up to 1 L with SFVV in a volumetric flask. • Mix 9.4 parts SFVV, 1 part Ultra Clorox®Germicidal Bleach, and 1 part 5% acetic acid. The resulting solution will have a pH of about 6.8 and a mean total chlorine content, estimated based on dilution, of about 6,200 ppin. The active decontaminating agents in this final solution arc hypochlorite (OCT) and hypochloraus acid. The effectiveness of bleach as a biological decontaminant is widely known. In previous testing of pH-amended bleach as a decontaminant. neutrali/ation of the bleach solution was achieved using STS. The bleach formulation used in this evaluation differed from that used in previous testing, so the determination of the neutrali/ation procedure was repeated to establish neutralization conditions appropriate for this evaluation. Application Procedure for Testing Based on previous test results with pH-amended bleach, and considering the topsoil surface material to be used in this testing, an application procedure for use in testing was developed. The intent of this procedure was to employ conventional and readily available equipment in a relatively simple application process. Trial runs were conducted to establish the appropriate concentration of STS for neutrali/ation of the pH-amended bleach. The pH-amended bleach was prepared fresh shortly before use on each day of testing, as described above. The pH of the solution was measured and recorded as part of the test data. A new non-corroding garden pump sprayer was used to apply the solution of pH-amended bleach to the test coupon surfaces. An identical sprayer was used to apply SFVV to positive control test coupons. Each sprayer was fitted with a pressure gauge to indicate the internal delivery pressure of the sprayer. The internal pressure of each sprayer was maintained in a normal range for use (i.e., 4 to 6 psi) throughout all applications. Based on laboratory tests, such a range of pressures produces a stable spray suitable for application on the scale of coupon testing. Testing of pH-amended bleach was conducted with two different contact times, i.e., 60 and 120 minutes. The step-by-step application procedure for the 60 minute contact time was: • Apply the pH-amended bleach solution to the test coupons (or SFVV to the positive control coupons) from a distance of about one foot (12 inches) using the sprayer at a delivery pressure within the specified range, until the test coupon surfaces arc fully wetted by the solution. • Re-apply the solution three times, i.e.. at 15 minutes after the first application. 30 minutes after the first application, and 45 minutes after the first application. • If necessary, pump up the pressure in the sprayer before application to maintain pressure within the specified range. • When 60 minutes have elapsed since the start of the first application, place the coupons into the extraction solution (containing the neutralization agent) along with any collected runoff of pH- anicnded bleach. The step-by-step application procedure for the 120 minute contact time was: • Apply the pH-amended bleach solution to the test coupons (or SFVV to the positive control coupons) from a distance of about one foot (12 inches) using the sprayer at a delivery pressure within the specified range, until the test coupon surfaces arc fully wetted by the solution. • Re-apply the solution seven times, i.e., at 15. 30, 45, 60, 75, 90, and 105 minutes after the first application. 31 ------- After each application, thoroughly mix the applied bleach solution with the soil in the test coupon, using a glass stirring rod. If necessary, pump up the pressure in the sprayer before application to maintain pressure within the specified range. When 120 minutes have elapsed since the start of the first application, place the coupons and each associated glass stirring rod into the extraction solution (containing the neutralization agent) along with any collected runoff of pH-amcnded bleach. ------- Appendix B: CASCAD Description and Application Procedure General Description CASCAD Surface Decontamination Foam (SDF) uses two liquid solutions (A and B) which react to form a foam as they arc mixed upon release from the application device. These two solutions arc made from three separate reagents, having chemical composition as follows: • CPA-2100 (dccontaininant) - solid reagent in powder form consisting of dichloraisocvanuric acid sodium salt. 70 to 100% by weight; • GPB-2100 (buffer) - solid reagent in powder form consisting of sodium tetraborate 10 to 30%, sodium hydroxide 1 to 5 %, and sodium carbonate 40 to 65% by weight; • GCE-2000 (surfactant) - liquid reagent consisting of sodium myristyl sulfate 10 to 30%, sodium (C14- 16) olefin sulfonate 10 to 30%, ethanol denatured 3 to 9%, alcohols (C10-16) 5-10%, sodium sulfate 3 to 7%, sodium xylene sulfonate 1 to 5%, and a proprietary mixture of sodium and ammonium salts along with water and co-solvent >9% by weight. The A and B solutions arc prepared from these reagents by the following procedure: 1. Make solution A by adding 31.2 g (four 7.8 g packets) of GPA-2100 to 250 mL of SFVV in a graduated cylinder, and then dilute with SFVV to 300 mL. 2. Mix with a micro stir bar until dissolved 3.Make solution B by adding 7.2 g (four 1.8 g packets) of GPB-2100 to 250 mL of SFVV in a graduated cylinder. 4. Mix with a micro stir bar until dissolved. 5. Add 18 mL (four 4.5 mL packets) of GCE-2000 to the solution from Step 4, mix, and then dilute with SFVV to 300 mL For use on the small scale needed for testing, a manual spray application bottle (the 600 mL Hand Held Decontamination System) has been developed by Allcn- Vanguard that draws solutions A and B from separate compartments and delivers them as a foam through a single spray head. To fill and operate the Hand Held System, follow these steps: 1. Pull the Locking Lever on the front of the bottle housing forward and lift. This will open the housing and expose the solution bottles, which arc labeled "A" and "B". 2. With the housing opened remove the caps (turn counter clockwise) and pull out the solution suction lines from the solution bottles. 3. With the caps and suction lines removed from both the "A" and "B" solution bottles: a. Pour solution A into the bottle labeled "A", and pour solution B into the bottle labeled "B". b. Assure that both bottles arc seated in the housing with the "B" bottle at the front. c. Place the suction lines back into the "A" and "B" bottles and tighten both "A" and "B" caps by turning them in a clockwise direction. 4. Hold the suction line up with one hand while closing the top of the housing with the other hand. Make certain that the Locking Lever snaps into its recess when the housing top closes. The suction line may be pinched closed if this procedure is not followed correctly; the condition of the line can be checked by looking through the housing at the suction line. 5. To use the 600 mL Hand Held Decontamination System, grasp the neck of the housing with your dominant hand and place the finger of this hand on the trigger of the foam nozzle. Aim the tip of the foam nozzle in the direction of the area to be decontaminated and pump the trigger. The trigger may have to be squeezed three or four times to evacuate the air in the suction line before foam is discharged. Application Procedure for Testing C ASC AD SDF was applied to soil coupons using the vendor-developed dual spray applicator. In previous testing, neutralization of the C ASC AD SDF was achieved by addition of 0.5% STS to the extraction 33 ------- solution. Trial runs were conducted before testing to establish the appropriate STS concentration for neutralization of the applied CASCAD SDF. Testing of C ASC AD SDF was conducted with two different contact times, 60 minutes and 120 minutes. In testing with a 60-minute contact time, each soil coupon was prepared by filling a 1 cm-deep glass Petri dish with soil; in testing with a 120-minute contact time, the same mass of soil was placed in a 3.5 cm-deep Teflon beaker having approximately the same internal diameter as the Petri dish. This difference was implemented to assure capture of the added depth of foam resulting from additional applications of the C ASC AD SDF. The step- by-step application procedures for testing of C ASC AD SDF with soil coupons was as indicated below. • Follow the instructions provided above for preparation of the reagent solutions and loading of the manual spray applicator. • Squeeze the trigger of the applicator head a few times while pointing the applicator into a laboratory sink or other waste container, until any air is cleared from the applicator and C ASC AD SDF is delivered from the applicator as a foam. For the 60-minute contact time: • Apply the C ASC AD SDF to the soil coupons using the manual applicator from a distance of about one foot (12 inches) while moving the nozzle, until the soil is entirely covered with no less than one (1) centimeter (3/8") deep foam. • Allow the foam to remain on the coupons for 30 minutes. • Reapply more C ASC AD SDF and allow the foam to remain on the coupons for an additional 30 minutes. • When a total of 60 minutes has elapsed since the first application, place each coupon into the extraction solution (containing the STS neutralization agent) along with any CASC AD SDF accumulated on the coupon. For the 120-minute contact time: • Apply the C ASC AD SDF to the soil coupons using the manual applicator from a distance of about one foot (12 inches) while moving the nozzle, until the soil is entirely covered with no less than one (1) centimeter (3/8") deep foam. • Allow the foam to remain on the coupons for 30 minutes. • Reapply more CASCAD SDF at 30 minutes, 60 minutes, and 90 minutes after the first application (for a total of four applications). • When a total of 120 minutes has elapsed since the first application, place each coupon into the extraction solution (containing the STS neutralization agent) along with any C ASC AD SDF accumulated on the coupon. After use, empty and clean the manual spray applicator according to the instructions below. Cleaning the Hand Held Decontamination System Clean the CASCAD SDF system after use by the following procedure. 1. Dump any remaining decontamination solution from both the "A" and "B" bottles and dispose of the solutions following appropriate waste procedures. 2. Thoroughly rinse both bottles with SFW, then fill each bottle with SFW. 3. Place the filled bottles back into the housing, insert the suction lines, and close the housing. 4. Pump the trigger until the suction lines and foam nozzle arc free from the decontamination solution. 5. Flush the interior and the exterior of the housing, and the caps used while mixing the solution, thoroughly with SFW. ------- Appendix C: Oxonia Actve Description and Application Procedure General Description Oxonia Active*, a liquid sanitizer made by Ecolab Inc.. consists of 27.5% hydrogen peroxide (H,0;) and 5.8% peroxyacetic acid (CH,C0(0,)H) by weight in water (density = 1.13 g/mL). Oxonia Active is used for sterilizing a variety of surfaces and containers in food, packaging, and other industries, and can be applied as a liquid or foam, or as droplets by fogging the target area. A temporary approval (crisis exemption) of Oxonia Active was granted by the U.S. Environmental Protection Agency for decontamination of Bacillus anthracis spores on non-porous surfaces, at defined temperatures, contact times, and dilution of the product. Application Procedure for Testing This application procedure for use of Oxonia Active on topsoil was developed in consultation with the vendor. The aim is to use a relatively simple application process that is likely to be effective when carried out with conventional and readily available equipment. Trial runs were conducted to establish the appropriate concentration of STS to be used in the spore extraction solution for neutrali/ation of Oxonia Active. For testing, a dccontaniinant solution containing 5,000 ppm peroxyacetic acid was prepared fresh daily by diluting 76 liiL of Oxonia Active to 1 L with SFVV. The Ecolab Pcroxyacid Test Kit was used for periodic verification of the peroxyacetic acid concentration in the undiluted Oxonia Active from which the decontaminant solution was prepared. A non-corroding garden pump sprayer was used to apply the diluted Oxonia Active solution to the test coupons. An identical sprayer was used to apply SFVV to positive control test coupons. Each sprayer was fitted with a pressure gauge to indicate the internal delivery pressure of the sprayer, which was maintained in a normal range for use (i.e., 4 to 6 psi) in all applications. Based on laboratory tests, such a range of pressures produces a stable spray, suitable for application on the scale of coupon testing. All applications were done at normal room temperature (approximately 20 °C (68 °F)). Testing of Oxonia Active was conducted with two different contact times. 60 minutes and 120 minutes. The step-by-step application procedure for Oxonia Active is shown below: For the 60-minute contact time: • Apply the dccontaniinant solution to the soil test coupons (or SFVV to the positive control coupons) from a distance of about one foot (12 inches) using the sprayer at a delivery pressure within the specified range. Spray the solution onto the coupons until the test coupons arc visibly wet. • Reapply the dccontaniinant solution if coupon surfaces become visibly dry, and regardless of the wetness of the coupons re-apply the dccontaniinant solution at 10 minute intervals after the initial application. • If necessary, pump up the pressure in the sprayer before application to maintain pressure within the specified range. • When 60 minutes have elapsed since the start of the first application, place each soil coupon into the extraction solution (containing the neutralization agent) along with any dccontaniinant solution accumulated on the coupon. For the 120-niinutc contact time: • Apply the dccontaniinant solution to the soil test coupons (or SFVV to the positive control coupons) from a distance of about one foot (12 inches) using the sprayer at a delivery pressure within the specified range. Spray the solution onto the coupons until the test coupons arc visibly wet. Stir the soil with a glass stirring rod to tlioroughly mix the soil with the applied dccontaniinant solution. Use a different glass stirring rod for each of the test and positive control coupons. • Reapply the dccontaniinant solution if coupon surfaces become visibly dry, and regardless of the wetness of the coupons re-apply the dccontaniinant solution at 10 minute intervals after the initial application. After each application stir the soil with a glass stirring rod to thoroughly mix the soil with the applied dccontaniinant solution. • If necessary, pump up the pressure in the sprayer before application to maintain pressure within the specified range. • When 120 minutes have elapsed since the start of the first application, rin.se each glass stirring rod with 10 inL of the extraction solution (containing the neutrali/ation agent) and place each 35 ------- corresponding coupon into the extraction solution along with any collected runoff of decontaminant solution. 36 ------- Appendix D: Klozur Description and Application Procedure General Description Klozur™ is a solid reagent made by FMC Corporation that is used for in situ and ex situ chemical oxidation of contaminants in environmental remediation applications. Klozur consists of sodium pcrsulfate (Na2S208) of purity > 99%, in the form of white, odorless crystals. In remediation applications, Klo/ur is injected into contaminated soil or groundwater, and activated by mixing in appropriate proportions with hy drogen peroxide (H ,0;) solutions of up to 8% H ,0, by weight, according to instructions published by FMC Corporation1. Activation of Klo/ur with H ,0; generates sulfate radicals (SO, •). which arc capable of destroying a wide range of organic contaminants. Application Procedure for Testing This application procedure for use of Klozur on topsoil was developed by EPA and Battcllc based on information published by the vendor. The aim is to use a relatively simple application process that is likely to be effective when carried out with conventional and readily available equipment. The procedure involves application of Klozur, followed by application of the H ,0, activating solution, consistent with the recommended approach for soil remediation. Trial runs were conducted to establish the appropriate concentration of STS to be used in the spore extraction solution for neutralization of the Klo/ur/ H,0, mixture after decontamination. For testing, a 0.5 M solution of pcrsulfate was prepared by dissolving 12 grams of Klozur in SFVV and diluting with SFVV to 100 inL final volume. This solution is 11.9% pcrsulfate by weight. Commercially prepared 8% H,0, solution was purchased for use in testing. Equal volumes of these Klo/ur and H ,0, solutions provide a molar ratio of 5:1 (H202:persulfate), which is a ty pical ratio for application in site remediation activities. Application of Klozur to the topsoil test coupons was done by injecting 1 inL of the 0.5 M pcrsulfate solution into each coupon using a laboratory pipet. and mixing the soil and pcrsulfate solution thoroughly using a glass stirring rod. A 1 inL volume of the 8% H ,0, activating solution was then applied to the coupon in the same manner and mixed with the soil using the same glass stirring rod. This process was repeated for multiple applications. All applications were done at normal room temperature (approximately 20 °C (68 °F)). Testing of Klozur was conducted with two different total contact times. 24 hours and 48 hours. The step-by-step application procedure for Klo/ur was: For the 24-hour contact time: • Inject 1 inL of the 0.5 M pcrsulfate solution into each test coupon and associated blank coupon. Mix the topsoil and pcrsulfate solution thoroughly using a glass stirring rod. Inject 1 inL of SFVV into each positive control coupon and associated blank coupon, and thoroughly mix the topsoil and SFVV with a glass stirring rod. (Use a different stirring rod for each topsoil coupon.) • Immediately inject 1 inL of 8% H;0, solution into each test coupon and associated blank coupon, and thoroughly mix the topsoil and injected solutions again with the stirring rod. Inject another 1 inL of SFVV into each positive control coupon and associated blank coupon, and thoroughly mix the topsoil and SFVV again with the stirring rod. • Repeat both application steps above at intervals of 60 minutes after the initial application, until a total of six applications have been made. • Keep all coupons in the test enclosure until 24 hours have elapsed since the first application, and then place each soil coupon into the extraction solution (containing the neutralization agent) along with all the dccontaminant solution accumulated on the coupon. For the 48-hour contact time: • Inject 1 inL of the 0.5 M pcrsulfate solution into each test coupon and associated blank coupon. Mix the topsoil and pcrsulfate solution thoroughly using a glass stirring rod. Inject 1 inL of SFVV into each positive control coupon and associated blank coupon, and thoroughly mix the topsoil and SFVV with a glass stirring rod. (Use a different stirring rod for each topsoil coupon.) • Immediately inject 1 inL of 8% H;0, solution into each test coupon and associated blank coupon, and thoroughly mix the topsoil and injected solutions again with the stirring rod. Inject another 1 inL of SFVV into each positive control coupon and associated blank coupon, and thoroughly mix the topsoil and SFVV again with the stirring rod. • Repeat both application steps above at intervals of 60 minutes after the initial application, until a total of six applications have been made. 37 ------- • Keep all coupons in the test enclosure until 48 hours have elapsed since the first application, and then place each soil coupon into the extraction solution (containing the neutralization agent) along with all the decontaminant solution accumulated on the coupon. ------- Reference Procedure for Activating Klozur™Persulfate with an 8% Hydrogen Peroxide Solution. Document 02-01-EIT-DH, FMC Corporation. Philadelphia. PA, Copyright 2008 FMC Corporation. All rights reserved ------- 40 ------- Printed on 100% recycled/recyclable paper with a minimum of 50% post-consumer fiber using vegetable-based ink. oEPA United States Environmental Protection Agency PRESORTED STANDARD POSTAGE & FEES PAID EPA PERMIT NO. G-35 Office of Research and Development (8101R) Washington, DC 20460 Official Business Penalty for Private Use $300 ------- |