Abstract:
A non-corrosive, liquid, aqueous sterilant composition (as a concentrate or ready-to-use solution), which may be provided in two parts which are mixed prior to application, may comprise a peracid (in an equilibrium solution with an underlying carboxylic acid or mixtures of alkyl carboxylic acids and peroxide), inorganic buffering agent, and water. It has been found that the use of this simplified system, even in the absence of additional components which have been thought to be desirable for sterilants used on metal parts (e.g., copper and brass corrosion inhibitors, chelating agents, anti-corrosive agents) display excellent performance and that these additional components are not necessary, and that the presence of these additional materials at least complicates disposal of the spent solutions and could complicate compatibility of the sterilant solutions with some polymeric materials, especially where organic materials are used as the additional components, which organic materials may interact with, dissolve or solubilize in the polymeric materials.

Description:
[0001]    The present invention relates to compositions which can be used to safely and effectively disinfect surfaces and articles against microbiological forms. The compositions are easily handled, tend to be non-corrosive to the types of polymeric, elastomeric and metal surfaces found in medical instruments, are relatively shelf-stable, and may be prepared quickly and easily by simply blending component solutions.  
           [0002]    The importance of the sterilization of medical instruments and implants has been understood for more than two centuries. The need for sterilization has become even more important recently with the appearance of strains of microbiological forms which are resistant to conventional microbiocides such as antibiotics. It has become very important to sterilize medical devices to kill or remove the more resistant strains of microbiological forms before they infect a patient. Additionally, the sterilants must be generally effective against microorganisms covering a wide range of classes and species, with U.S. Government standards requiring efficacy against both bacteria and spores.  
           [0003]    Sterilization of medical devices has been performed for many years by immersing the medical devices in an atmosphere which is antagonistic to the survival of the microbiological forms. Among the environments which have been used to attempt to sterilize medical instruments include, but is not limited to, steam, alcohols, ethylene oxide, formaldehyde, gluteraldehyde, hydrogen peroxide, and peracids. Each of these materials has its benefits and limitations. Ethylene oxide tends to be very effective against a wide range of microorganisms, but it is highly flammable and is generally used in a gas phase which may require more stringent environmental restraints than would a liquid. Alcohols are similarly flammable and must be used in very high concentrations. Steam has a more limited utility, having to be used in a controlled and enclosed environment, requiring the use of large amounts of energy to vaporize the water, and requiring prolonged exposure periods to assure extended high temperature contact of the steam with the organisms. Hydrogen peroxide has limited applicability because it is unstable and not as strong as some other sterilants. The peracids have become more favorably looked upon, but they tend to be corrosive (being an oxidizing acid) and are not shelf stable.  
           [0004]    U.S. Pat. No. 5,508,046 describes a stable, anticorrosive peracetic acid/peroxide sterilant comprising a concentrate including peracetic acid, acetic acid, hydrogen peroxide (in a ratio of 1:1 to 11:1 total acid/hydroxide), and 0.001 to 200 parts per million of stabilizers such as phosphonic acids and sodium pyrophosphates. The concentrates are diluted about 20 to 40 times so that the maximum concentration of stabilizer in the use solution would be about 10 parts per million. The stabilizers are described as acting as chelating agents by removing trace metals which accelerate the decomposition of the peroxides.  
           [0005]    U.S. Pat. No. 5,616,616 describes a room temperature sterilant particularly useful with hard tap water comprising an ester of formic acid, an oxidizer (such as hydrogen peroxide or urea hydrogen peroxide), performic acid and water. The use of corrosion inhibitors (such as benzotriazoles, azimidobenzene, and benzene amide) and stabilizers (unnamed) is also generally suggested.  
           [0006]    U.S. Pat. No. 5,077,008 describes a method of removing microbial contamination and a solution for use with that method. The solution comprises a combination of five ingredients in water: 1) a strong oxidant (including, for example, organic peroxides, peracids, an chloride releasing compounds, with peracetic acid in a concentration of 0.005 to 1.0% being preferred), 2) a copper and brass corrosion inhibitor (e.g., triazoles, azoles and benzoates), 3) a buffering agent (including, for example, phosphate), 4) at least one anti-corrosive agent which inhibits corrosion in at least aluminum, carbon steel and stainless steel selected from the group consisting of chromates and dichromates, borates, phosphates, molybdates, vanadates and tungstates, and 5) a wetting agent. A sequestering agent may be used to prevent the phosphates from causing precipitation in hard water.  
           [0007]    U.S. Pat. Nos. 4,892,706 and 4,731,22 describe automated liquid sterilization systems having a plurality of modules which store the sterilant solution and the rinse solution. U.S. Pat. No. 5,037,623 describes a sterilant concentrate injection system which is a spill resistant, vented ampule system for use with sterilization systems.  
           [0008]    Medical devices now include many polymeric components for reasons of material costs and ease of manufacture. Many of the systems and solutions designed for the sterilization of metal medical devices are not necessarily suitable for use with polymeric components, and may cause corrosion of the polymeric materials. It is therefore necessary to formulate sterilization compositions which are compatible with both metal and polymeric components of the medical devices. It is also always desirable to provide sterilization systems with fewer components in the composition, where the sterilization solutions do not significantly sacrifice microbiocidal activity and do not corrode the materials used in medical devices.  
         SUMMARY OF THE INVENTION  
         [0009]    A non-corrosive, liquid, aqueous sterilant composition (as a concentrate or ready-to-use solution), which may be provided in two parts which are mixed prior to application, may comprise a peracid (in an equilibrium solution with an underlying carboxylic acid or mixtures of alkyl carboxylic acids and peroxide), inorganic buffering agent, and water. It has been found that the use of this simplified system provides excellent sterilization ability, even in the absence of additional components which have been thought to be desirable for sterilants used on metal parts (e.g., copper and brass corrosion inhibitors, chelating agents, anti-corrosive agents) which have been found to not be necessary. The presence of these additional materials at least complicates disposal of the spent solutions and could complicate compatibility of the sterilant solutions with some polymeric materials, especially where organic materials are used as the additional components, which organic materials may interact with, dissolve or solubilize in the polymeric materials.  
           [0010]    The concentration of the components has shown itself to be important in providing non-corrosive effects towards a wide variety of structural materials in medical devices and yet providing effective sterilization effects against spores and bacteria, including tuberculosis bacteria in an acceptable amount of time.  
           [0011]    An aqueous sterilant use solution according to the present invention may comprise a solution having a pH of from 5.0 to 7.0 comprising from 100 to 10,000 parts per million of a peroxy acid and 30 to 5000 parts per million of buffering agent, preferably without any organic anticorrosive agents. The aqueous sterilant solution may, for example, comprise from 100 to 10,000 parts per million of a peroxy acid, 30 to 5000 parts per million of buffering agent and a catalytically effective amount of a catalyst for peroxygenation of a carboxylic acid by hydrogen peroxide.  
           [0012]    The aqueous sterilant solution may consist essentially of a solution having a pH of from 5.0 to 7.0 comprising from 100 to 10,000 parts per million of a peroxy acid, 30 to 5000 parts per million of buffering agent and a catalytically effective amount of a catalyst for peroxygenation of a carboxylic acid by hydrogen peroxide.  
           [0013]    The method may particularly comprise mixing a first and a second solution to form a sterilizing solution comprising a peroxy acid, said first solution comprising a carboxylic acid, hydrogen peroxide and water, and said second solution comprising a buffering agent for pH between about 5 and 7, said sterilizing solution comprising at least 100 parts per million of peroxy acid at a pH of 5 to 7, immersing said article in said sterilizing solution for at least 5 minutes to sterilize said article, said first solution and second solution being free of organic anti-corrosion agents for brass and/or copper, and said article comprising a medical article having parts made of at least two materials selected from the group consisting of metals, polymers and rubbers.  
         DETAILED DESCRIPTION OF THE INVENTION  
         [0014]    The aqueous sterilant compositions of the present invention comprise a peracid, water-soluble peroxide source, and carboxylic acid in a buffered solution at pH levels between about 5.0 and 7.0. The use of an inorganic buffering agent also enables the use of slightly water-soluble, higher molecular weight carboxylic acids in the formation of peroxy acids with the peroxide source thereby reducing the amount of deposits from fatty acid residue in the solution. Phosphate buffers are effective dispersants and suspending agents for these fatty acid residues.  
           [0015]    The peroxy acid useful in the practice of the present invention may comprise any organic peroxy acid. These acids are well known in the art to be formed from any carboxylic acid containing compound. Normally they are prepared from carboxylic acids of the formula:  
           CH 3 —(CH 2 )n-COOH  
           [0016]    wherein n is 0 to 18, preferably 0 to 12 and more preferably 0 to 10, with the corresponding peroxy acid having the formula:  
           CH 3 —(CH 2 )n-CO 3 H  
           [0017]    wherein n is as defined above. The alkyl moiety on the acid, CH 3 —(CH 2 )n- may be replaced with hydrogen or any, preferably low molecular weight, organic group so that the acid and the resulting peroxy acid may be represented by: R—CO 2 H and R—CO 3 H, respectively. The molecular weight of R could be 1, but preferably should be between 15 and 155.  
           [0018]    Carboxylic acids which are generally useful in the invenetion are those which comprise percarboxylic acids. Percarboxylic acids generally have the formula R(Co 3 H n ), where R is an alkyl, arylaklyl, cycloalkyl, aromatic or heterocyclic group, and N is 1, 2, or 3 and named by prefixing the parent acid with peroxy.  
           [0019]    The peracid normally exists in an equilibrium state with the original or fundamental acid and the peroxide source, usually hydrogen peroxide. Typical peracids include peracids of C 1  to C 12  carboxylic acids such as formic acid, acetic acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, and the like. The term carboxylic acids as used in the practice of the present invention, unless otherwise limited, also includes mono- and di-hydroxycarboxylic acids such as glycolic acid, lactic acid and citric acid. An example of di-hydroxycarboxylic acid or di-hydroxy is tartaric acid, and also fumaric acid, which is an unsaturated di-hydroxycarboxylic acid. Diacids such as alpha-omega-dicarboxylicpropanoic acid, succinic acid, glutaric acid, adipic acid, and the like may also be used to form di-peracids. Peroxycarboxylic acids may also be present and included within the solutions of the present invention. Mixtures and combinations of the peracids may also be used in the systems of the invention, as well as other addenda as generally described herein.  
           [0020]    The peroxide source is preferably an aqueous solution of hydrogen peroxide, but may also include such alternative peroxide sources as solutions of sodium peroxide, calcium peroxide, alkali salts of percarbonate and persulfate, and even organic peroxides such as dicumyl peroxide, dialkyl peroxides, urea peroxide, and the like, forming the basis of the solution of the hydrogen peroxide. The inorganic peroxides are preferred as the source of the solution of the hydrogen peroxide. The ratio of the peroxy acid to the hydrogen peroxide can also significantly influence the efficacy of the solutions of the invention, with higher ratios of the peroxy acid to the hydrogen peroxide preferred. For example, its is more desirable to have a ratio of at least 2:1 or 3:1 (peroxy acid to hydrogen peroxide), and more desirable to have higher ratios of at least 4:1, at least 5:1 or at least 8:1 or more (peroxy acid to hydrogen peroxide).  
           [0021]    The buffering agent is a compound, again preferably an inorganic compound which will maintain a buffered pH level in the solution of the composition between 5.0 and 7.0. Buffering agents include, but are not limited to phosphates, borates, lactates, acetates, citrates, vanadates, tungstates, and combinations thereof, particularly alkali metal or alkaline metal salts of these agents. The use of phosphates exclusively or at least primarily (e.g., at least 50%, at least 65%, at least 75%, or at least 90 or 95% by weight of the buffering agents) is particularly useful. Trisodium phosphate has been found to be particularly desirable because of its ability to maintain the acid residues of the peroxy acids in solution where they will not form film in the solution which can be picked up by any sterilization apparatus or medical device which is being sterilized. It is interesting to note that phosphates have been generally taught to be avoided in sterilization solutions where hard water may be contacted because of the potential for calcium precipitation, yet in the present invention, the presence of phosphates reduces the formation of organic residue film on the surface of the solution. The buffering agent alone, even when a phosphate or especially when a phosphate and particularly trisodium phosphate, has been found to reduce corrosion by the solution on all surfaces. The use of phosphate(s) alone, in the absence of copper and brass corrosion inhibitors has been found to be an effective sterilant, and provide non-corrosive activity against a wide range of structural materials, including, but not limited to rubbers, plastics and metals, such as stainless steel, aluminum, polypropylene, teflon, acrylonitriletstyrenetbutadiene, polyolefins, vinyl resins (e.g., polyvinyl chloride, polyvinylbutyral), silicone resins and rubbers, and polyurethanes, and provide second tier protection for brass and copper. Although the peracids work more efficiently in their microbiocidal activity at highly acidic pH levels (below 4.0), those acidic levels are much more corrosive. The use of a buffering system which maintains the pH above 5.0 and preferably between about 5.0 and 7.0 still provides a microbiocidal activity at levels which meet all international standards, using anywhere from 150 to 10,000 parts per million peracid.  
           [0022]    The sterilant can be used as a manual system or be used in an automated system. The sterilant can be provided as a one-part or preferably two part concentrate, with the peracid in one solution and the buffer in the second solution. For example, in a two-part system, a peracid concentrate may be formed having 0.01% to 1% by weight peracid (e.g., peracetic acid), 0.003% to 1% by weight ppm hydrogen peroxide, 0.01% to 1% by weight acid (e.g., acetic acid), and the buffer solution may comprise, for example, from 0.5 to 75,000 ppm buffering agent (e.g., anhydrous trisodium phosphate) in water. Mixtures of these types of addenda, including the buffering agents and peracids, are clearly useful in the practice of the present invention. It is preferred that the concentrates have active ingredient contents at the higher levels of these ranges such as 0.1% to 15% by weight peracid, 5% to 80% by weight peroxide, 5% to 80% by weight acid and 0.1% to 15% by weight buffering agents. The diluted to use solution would preferably contain sufficient actives to provide 0.01% to 1.0% by weight peracid at a pH between about 5.0 and 7.0. The use solution need not contain any effective amount of many of the additives which prior art systems have required for non-corrosive effects (such as the organic anti-corrosive agents such as the triazines, benzotriazoles, azoles and benzoates), and yet provide a wider disclosed range of non-corrosivity against the many available surfaces of medical devices. The use solutions of the present invention may comprise a simplest solution comprising peracid (along with the acid and peroxide in equilibrium), buffering agent in an amount to provide a pH of from about 5.0 to 7.0, and water (preferably deionized water). This solution may be modified by the addition of individual agents such as chelating agents, surfactants (also referred to in the literature for sterilant compositions as wetting agents), and anti-corrosion agents. A typical concentrate solution which may be diluted to a use solution might comprise, 0.1% to 15% by weight peracid, 0.1% to 15% by weight buffering agent[, with the remainder as water and other addenda as generally described herein (e.g., from 99.6 to 78% by weight water). These and other aspects of the invention will be further described by reference to the following, non-limiting examples.  
           [0023]    These data show that a preferred range for the concentration of peroxide in the solution (particularly as evidenced by hydrogen peroxide) less than 150 ppm, preferably less than 100 up to 80,000 ppm, still more preferably less than 100, less than 75 and less than 50 ppm. In the examples, POAA represents peroxyacetic acid, AA represents acetic acid, POOA represents peroxyoctanoic acid, and Oct. Acid represents octanoic acid. Dequest™ are commercially available materials which may be used in the solutions of the present invention. Dequest™ 2000 comprises aminotri(methylene-phosphonic acid), Dequest™ 2010 comprises 1-hydroxyethylidene-1,1-diphosphonic acid, and Dequest™ 2006 comprises aminotri(methylene-phosphonic acid) pentasodium salt. Dequest acts as a chelator for heavy metals. The data also shows that sporicidal activity of compositions with higher molecular weight peracids increase with higher proportions of the peracid as compared to the acid.  
           [0024]    The presence of a catalyst for the formation of the peracid in the sterilization compositions of the present invention also is a novel aspect of the present invention which could act to maintain the level of peracid in the solution during use. 
       
    
    
     CORROSION EXAMPLE I  
       [0025]    Experimental  
         [0026]    In the following comparison example, a formulation according to the present invention comprising 2.69 weight percent of a 13% solution of peracetic acid made by combining 78% glacial acetic acid, 21% hydrogen peroxide (35% by weight in water), and 1% hydroxyethylenediamine phosphonate was compared to a commercial sterilization formulation (CSF) comprising a mixture of sodium perborate and tetraacetyl ethylenediamine with a buffer to provide a use solution of pH 8, with its necessary sterilization activator. The CSF composition (referred to as Powder PAA) comprises a powder source of peracetic acid (with a solid peroxide source) without a buffering agent, and was compared to a liquid solution of peracetic acid (PAA) made according to the present invention (referred to as Liquid PAA) by admixture of acetic acid and hydrogen peroxide solution with 1% by weight of hydroxyethylenediamine phosphonate catalyst to form the solution of peracetic acid (with the equilibrium amounts of acetic acid and hydrogen peroxide) at a pH of 6.0 provided by 3.0% by weight trisodium phosphate. This commercial CSF product requires mixing of a dry powder, with a delay required for the activator TAED (tetra acetyl ethylene diamine) by reaction with sodium perborate to generate peracetic acid and microbiocidal activity in the components.  
         [0027]    Test Parameters:  
         [0028]    The test was performed on pieces of an Olympus flexible endoscopes using a washer/disinfector to reduce manual variables. The test parameters were room temperature conditions, with the following immersion times:  
                                                       Sample   Cycles   Immersion Time                           Liquid PAA   1   10 minutes           Powder PAA   1   15 minutes           Sample   Application Time           Liquid PAA   24 hours           Powder PAA    8 hours                      
 
         [0029]    The test was performed by completely immersing separate test pieces S1 to S7 and W1 to W28 in each of the solutions.  
                                                                   Test Pieces                Item   Parts                       S1-S7   Parts of endoscope           S8 and S9   Insertion tube           S10   Light guide tube           W1-W28   Parats of washer/disinfector                        Sample       Surface           No.   Material (base)   Control   Place of the Parts               S1   A5056BD-H32 Resin   black   connector to LS               painting       S2   Polysulfone   black   main body               painting       S3   SUS304 Resin   El. black   outside (hidden)               coating       S4   Silicone Rubber   —   outside       S5   Polybutadiene PB-60   —   outside       S6   Mod. PPO   black   main body           Polyphenyleneoxide   painting       S7   A5056BD-H32 Resin   black   eyepiece               alumite       S   Polyurethane   primary   insertion tube               coat Z       S   Polyurethane   primary   insertion tube               coat V       S   Polyurethane       light guide cable       W1   Stainless Steel       inner pipe system       W2   Stainless Steel       inner pipe system       W3   epoxy resin+coating       heating panel       W4   Polyethylene       basin       W5   Polypropylene       basin       W6   Polyacetate       connector       W7   Polysulfone       part of top cover       W8   Silicone Rubber       sealing       W9   Polyvinyl chloride       inner pipe system       W10   Polyvinyl chloride (hard)       inner pipe system       W11   Acrylic polymer       parts in the basin       W12   Ethylene/propylene       inner pipe system       W13   Ethylene/propylene rubber       inner pipe system       W14   Acrylate modified       top cover           PolyVinylChloride       W15   Butyl-nitrile rubber +       parts in the basin           Phenol       W16   Teflon       name plate in basin       W17   Butyl-nitrile rubber       sealing       W18   Polyurethane       ?       W19   Acrylonitrile/butadiene/       top cover           styrene       W20   modified PPO       top cover       W21   Butyl rubber       sealing       W22   fluorinated rubber       sealing       W23   alumina ceramic       parts of pump system       W24   Teflon       parts of pump system       W24   Teflon rubber       parts of pump system                  
 
       CONCLUSION  
       [0030]    The samples were carefully inspected to evaluate the cosmetic effects (corrosion effects) on the various pieces. The first examination (Item 1) was for parts of the endoscope. The second examination (Item 2) was for the insertion tube. The third examination (Item 3) was for the light guide tube. The fourth examination (Item 4) was for the washer/disinfector. The samples performed substantially identically, with both solutions showing only a slight cosmetic change in painted black surface of the endoscope (S3 surface). No functional or cosmetic changes were noted on any other sample. The simplicity of use for the Liquid PAA system was very noteworthy, with no delay in mixing or reaction time. The solutions could be directly added into an automated system while the CSF Powder PAA system would have required premixing and activation time before it could have been used in an automatic system.  
       CORROSION EXAMPLE II  
       [0031]    Experimental A corrosion study was performed to evaluate peracid containing formulas with and without buffer addition upon selected metals, plastics and rubbers.  
         [0032]    Testing was conducted with two peracid formuations of 500 ppm (parts per million) peracetic acid (A) and 5000 ppm peracetic acid (B) concentration without buffer; and, two identical formulas (C and D respectively) with exception of buffer addition admixture.  
         [0033]    Coupons were completely immersed in 200 mls of defined test solution contained in covered 8 ounce glass jars maintained at 50° C. within an environmental chamber. Solutions were changed daily. Study was conducted over a 14 day time period. For each test material, a control was also run which is a coupon of stated material placed within a covered 8 ounce glass jar having no test solution.  
         [0034]    Coupons were pretreated before the corrosion study began, and postreated before final comparitive measurements and visual observations were performed. Metal coupons were precleaned according to ASTM Vol. 3.02, G31-72 and 3.02, G1-90 protocol and post-treated accordingly prior to final measurement. Test conditions were modified from the ASTM protocol as explained in above paragraph. Plastic and rubber coupons were only rinsed with deionized water and air dried prior to corrosion study; and, similarly treated prior to final measurement and visual observation.  
       CONCLUSION  
       [0035]    Addition of buffer admixture to peracetic acid composition test solutions significantly improves metals protection. The effect is less noticeable on test plastics; but, protection is provided selected test rubbers.  
                                                 PART IA: FORMULA - PERACID COMPONENT       HIGH POAA - LOW H202 PERACID FORMULA KX-6091                        GM/       ITEM   RAW MATERIAL   WT. %   10000               10   Acetic Acid    78.00    7800.00       20   Hydrogen Peroxide 35%    21.00    2100.00       30   Dequest ™ 2010 (60%)    1.00    100.00           Total   100.00   10000.00                                  
 
         [0036]    [0036]                                                                                                                                         PART IB: FORMULA - ADMIXTURE OF IA       AND BUFFER COMPONENT       FORMULAS A, B, C, D       CORROSION STUDY USE DILUTIONS                (A)   (B)   (C)   (D)                        GM/       GM/       GM/       GM/       ITEM   Material   WT. %   4500   WT. %   4500   WT. %   4500   WT. %   4500                    10   Deionized   99.10556   4459.75   90.66311   4079.84   99.55756   4480.09   95.57511   4300.88           Water       20   Trisodium   0.45200   20.41   4.91200   221.04           Phosphate           Anhyd.           Gran.       30   KX-6091   0.44244   19.91   4.42489   199.12   0.44244   19.91   4.42489   199.12           (11.3%           POAA)           Total   100.00000   4500.07   100.00000   4500.00   100.00000   4500.00   100.00000   4500.00           THEORETICAL   ppm   pH   ppm   pH   ppm   pH   ppm   pH           VALUES           POAA   500   6.00   5000   6.00   500   3.00   5000   2.50                                                                            
         [0037]    [0037]                                                                                                                                   PART II: CORROSION - METALS       14 day Compatibility Test of 15 different materials tested against four different Test       Solutions at 50° C. with the test solutions are changed daily.                    Material   Initial Wt.   Final Wt.                       Test item   Test Solution   METALS   (gms)   (gms)   TWL   CWL   AWL   mpy                1   (A) 500 ppm POAA/Buffered   316 SS   23.5792   23.5791   0.0001   0.0001   0.0000   0.0000        5   (B) 5000 ppm POAA/Buffered   316 SS   23.5194   23.5193   0.0001   0.0001   0.0000   0.0000        9   (C) 500 ppm POAA only   316 SS   23.5764   23.5762   0.0002   0.0001   0.0001   0.0031       13   (D) 5000 ppm POAA only   316 SS   23.5690   23.5689   0.0001   0.0001   0.0000   0.0000       17   CONTROL   316 SS   23.5846   23.5845   0.0001   0.0001        2   (A) 500 ppm POAA/Buffered   304 SS   17.9651   17.9650   0.0001   0.0000   0.0001   0.0031        6   (B) 5000 ppm POAA/Buffered   304 SS   17.9326   17.9323   0.0003   0.0000   0.0030   0.0938       10   (C) 500 ppm POAA only   304 SS   17.9795   17.9793   0.0002   0.0000   0.0002   0.0063       14   (D) 5000 ppm POAA only   304 SS   17.9993   17.9992   0.0001   0.0000   0.0001   0.0031       18   CONTROL   304 SS   18.1102   18.1102   0.0000   0.0000        3   (A) 500 ppm POAA/Buffered   7075   12.8716   12.8685   0.0031   0.0002   0.0029   0.2412               Aluminum        7   (B) 5000 ppm POAA/Buffered   7075   12.7575   12.7336   0.0239   0.0002   0.0237   1.9712               Aluminum       11   (C) 500 ppm POAA only   7075   12.8651   12.8392   0.0259   0.0002   0.0257   2.1376               Aluminum       15   (D) 5000 ppm POAA only   7075   12.8718   12.7439   0.1279   0.0002   0.1277   10.6213               Aluminum       19   CONTROL   7075   12.4899   12.4897   0.0002   0.0002               Aluminum        4   (A) 500 ppm POAA/Buffered   260 Brass   26.4108   26.3763   0.0345   0.0004   0.0341   0.9779        8   (B) 5000 ppm POAA/Buffered   260 Brass   26.4211   26.3307   0.0904   0.0004   0.0900   2.5809       12   (C) 500 ppm POAA only   260 Brass   26.6471   25.6695   0.9776   0.0004   0.9772   28.0233       16   (D) 5000 ppm POAA only   260 Brass   26.4949   18.9759   7.5190   0.0004   7.5186   215.6118       20   CONTROL   260 Brass   26.4352   26.4348   0.0004   0.0004                    PART II: CORROSION - METALS - OBSERVATIONS            Test       Material           item   Test Solution   METALS   Visual Obervations                1   (A) 500 ppm POAA/Buffered   316 SS   Smooth, shiny silver colored material like control        5   (B) 5000 ppm POAA/Buffered   316 SS   Smooth, shiny silver colored material like control        9   (C) 500 ppm POAA only   316 SS   Smooth, shiny silver colored material like control       13   (D) 5000 ppm POAA only   316 SS   Smooth, shiny silver colored material like control       17   CONTROL   316 SS   Smooth, shiny silver colored material        2   (A) 500 ppm POAA/Buffered   304 SS   Smooth, shiny silver colored material like control        6   (B) 5000 ppm POAA/Buffered   304 SS   Smooth, shiny silver colored material like control       10   (C) 500 ppm POAA only   304 SS   Smooth, shiny silver colored material like control       14   (D) 5000 ppm POAA only   304 SS   Smooth, shiny silver colored material like control       18   CONTROL   304 SS   Smooth, shiny silver colored material        3   (A) 500 ppm POAA/Buffered   7075 Aluminum   A slt. duller, slt. whiter than control, silver material        7   (B) 5000 ppm POAA/Buffered   7075 Aluminum   A very dull, smokey brown colored material       11   (C) 500 ppm POAA only   7075 Aluminum   A dull, whitish gray colored material       15   (D) 5000 ppm POAA only   7075 Aluminum   A very dull, very whitish gray colored material       19   CONTROL   7075 Aluminum   A slt. dull, silver colored material        4   (A) 500 ppm POAA/Buffered   260 Brass   A mixture of dull gold &amp; pink area colored material        8   (B) 5000 ppm POAA/Buffered   260 Brass   A dull, gold colored material with patches of pink       12   (C) 500 ppm POAA only   260 Brass   A darker dull gold colored material with pink areas       16   (D) 5000 ppm POAA only   260 Brass   A sparkling grainy gold colored material       20   CONTROL   260 Brass   A smooth, shiny, gold colored material                    KX-6091 CORROSION STUDY       CALCULATION DATA                4 Metals   DENSITY   AREA in inches squared                        316 Stainless Steel   7.98   6.5            304 Stainless Steel;   7.94   6.4           7075 Aluminum   2.81   6.8            260 Brass   8.5     6.52                            Time &amp; Temp Tested                       14 days at 50° C.           mpy = (534,000 * AWL)/(A * T * D)                                                                                                            
         [0038]    [0038]                                                                                                                   PART III: CORROSION - PLASTICS       Analytical - Observations       KX-6091 CORROSION STUDY       14 day Compatibility Test of 15 different materials tested against four differnt Test       Solutions at 50° C. with the test solutions are changed daily.                                                                    %                   Initial   Initial   Initial   Initial   Final   %   Final   %   Final   %   Final   Thick       Test   Test   Material   Wt.   Ht.   Width   Thick   Wt.   Weight   Ht.   Height   Width   Width   Thick   Chang-       item   Solution   PLASTICS   (gms)   (inches)   (Inches)   (inches)   (gms)   Change   (inches)   Change   (inches)   Change   (inches)   es               21   (A) 500   Polyurethane   3.8348   2.996   0.506   0.128   3.8360   0.0313   2.996   0.0000   0.507   0.1976   0.128   0.0000           ppm           POAA/           Buffered       27   (B) 5000   Polyurethane   3.8379   2.996   0.502   0.129   3.8385   0.0156   2.998   0.0668   0.502   0.0000   0.128   −0.7752           ppm           POAA/           Buffered       33   (C) 500   Polyurethane   3.8385   2.999   0.505   0.128   3.8418   0.0860   3.004   0.1567   0.505   −0.1976   0.127   −0.7813           ppm           POAA           only       39   (D) 5000   Polyurethane   3.8151   2.995   0.504   0.127   3.7411   −1.9397   3.061   2.2037   0.509   0.9921   0.125   −1.5748           ppm           POAA           only       45   CON-   Polyurethane   3.8286   2.996   0.505   0.128   3.8200   −0.2248   2.993   −0.1001   0.504   −0.1980   0.128   0.0000           TROL       22   (A) 500   Polyethylene   1.3741   2.991   0.505   0.066   1.3736   −0.0364   2.991   0.0000   0.504   −0.1980   0.066   0.0000           ppm           POAA/           Buffered       28   (B) 5000   Polyethylene   1.3676   2.991   0.505   0.064   1.3675   −0.0073   2.991   0.0000   0.505   0.0000   0.065   1.5625           ppm           POAA/           Buffered       34   (C) 500   Polyethylene   1.3541   2.992   0.504   0.065   1.3541   0.0000   2.991   −0.0334   0.502   −0.3968   0.065   0.0000           ppm           POAA           only       40   (D) 5000   Polyethylene   1.3586   2.995   0.504   0.066   1.3593   0.0515   2.994   −0.0334   0.502   −0.3968   0.066   0.0000           ppm           POAA           only       46   CON-   Polyethylene   1.3668   2.991   0.504   0.068   1.3667   −0.0073   2.989   −0.0669   0.504   0.0000   0.068   0.0000           TROL       23   (A) 500   Polypropylene   1.3792   3.002   0.504   0.066   1.3792   0.0000   3.001   −0.0333   0.503   −0.1984   0.067   1.5152           ppm           POAA/           Buffered       29   (B) 5000   Polypropylene   1.3774   2.998   0.503   0.065   1.3775   0.0073   2.999   0.0334   0.503   0.0000   0.066   1.5385           ppm           POAA/           Buffered       35   (C) 500   Polypropylene   1.3793   2.998   0.504   0.065   1.3796   0.0218   2.998   0.0000   0.503   −0.1984   0.065   0.0000           ppm           POAA           only                           Initial   Initial   Initial   Initial   Final   %   Final   %   Final                   Test   Test   Material   Wt.   Ht.   Width   Thick   Wt.   Weight   Ht.   Height   Width       item   Solution   PLASTICS   (gms)   (inches)   (Inches)   (inches)   (gms)   Change   (inches)   Change   (inches)   0.0000   0.065   0.0000               47   CON-   Polypropylene   1.3812   2.997   0.503   0.065   1.3811   −0.0072   2.997   0.0000   0.503   0.0000   0.065   0.0000           TROL       24   (A) 500   Polyvinyl   2.1801   3.002   0.505   0.066   2.1843   0.1927   3.002   0.0000   0.506   0.1980   0.065   −1.5152           ppm   Chloride           POAA/           Buffered       30   (B) 5000   Polyvinyl   2.2005   2.997   0.505   0.066   2.2041   0.1636   2.997   0.0000   0.506   0.1980   0.066   0.0000           ppm   Chloride           POAA/           Buffered       36   (C) 500   Polyvinyl   2.1734   2.998   0.505   0.065   2.1777   0.1978   2.998   0.0000   0.505   0.0000   0.065   0.0000           ppm   Chloride           POAA           only       42   (D) 5000   Polyvinyl   2.1590   2.998   0.505   0.065   2.1625   0.1621   2.997   −0.0334   0.505   0.0000   0.065   0.0000           ppm   Chloride           POAA           only       48   CON-   Polyvinyl   2.2048   2.999   0.505   0.056   2.2037   −0.0499   2.998   −0.0333   0.505   0.0000   0.056   0.0000           TROL   Chloride       25   (A) 500   ABS   1.4724   2.995   0.507   0.061   1.4762   0.2581   2.999   0.1336   0.508   0.1972   0.061   0.0000           ppm           POAA/           Buffered       31   (B) 5000   ABS   1.5167   3.003   0.507   0.063   1.5201   0.2242   3.006   0.0999   0.506   −0.1972   0.063   0.0000           ppm           POAA/           Buffered       37   (C) 500   ABS   1.5082   3.000   0.507   0.062   1.5132   0.3315   3.004   0.1333   0.508   0.1972   0.062   0.0000           ppm           POAA           only       43   (D) 5000   ABS   1.4971   2.995   0.505   0.062   1.5047   0.5076   3.000   0.1669   0.510   0.9901   0.062   0.0000           ppm           POAA           only       49   CON-   ABS   1.4822   2.995   0.507   0.062   1.4813   −0.0607   2.995   0.0000   0.508   0.1972   0.062   0.0000           TROL       26   (A) 500   Polyacetal   4.4596   3.003   0.507   0.133   4.5033   0.9799   3.010   0.2331   0.508   0.1972   0.134   0.7519           ppm           POAA/           Buffered       32   (B) 5000   Polyacetal   4.3970   3.003   0.507   0.131   4.4302   0.7551   3.009   0.1998   0.507   0.0000   0.132   0.7634           ppm           POAA/           Buffered       38   (C) 500   Polyacetal   4.4967   3.004   0.506   0.134   4.5441   1.0092   3.014   0.3329   0.508   0.3953   0.135   0.7463           ppm           POAA           only       44   (D) 5000   Polyacetal   4.3832   3.003   0.507   0.131   4.4264   0.9856   3.012   0.2997   0.508   0.1972   0.132   0.7634           ppm           POAA           only       50   CON-   Polyacetal   4.4498   3.002   0.506   0.133   4.4454   −0.0989   3.000   −0.0666   0.506   0.0000   0.133   0.0000           TROL                    Test       Material           item   Test Solution   PLASTICS   Visual Observations               21   (A) 500 ppm POAA/Buffered   Polyurethane   Dull opaque orange material with semi-transparent boarder       27   (B) 5000 ppm POAA/Buffered   Polyurethane   Dull opaque orange material with semi-transparent boarder                   and slt. tacky       33   (C) 500 ppm POAA only   Polyurethane   Dull darker opaque orange material with semi-transparent                   boarder and slt. tacky       39   (D) 5000 ppm POAA only   Polyurethane   Very dark orange, very tacky, completely opaque material that                   stuck to drying surface resulting in loss of material       45   CONTROL   Polyurethane   A dull, dirty, slt. yellow tinted, semi-transparent material       22   (A) 500 ppm POAA/Buffered   Polyethylene   Slt. whiter material than control       28   (B) 5000 ppm POAA/Buffered   Polyethylene   Slt. whiter material than control       34   (C) 500 ppm POAA only   Polyethylene   Slt. whiter material than control       40   (D) 5000 ppm POAA only   Polyethylene   Slt. whiter material than control       46   CONTROL   Polyethylene   A dull, grayish white material       23   (A) 500 ppm POAA/Buffered   Polypropylene   A white filmy, faintly transparent, more cloudy material than                   control       29   (B) 5000 ppm POAA/Buffered   Polypropylene   A white filmy, faintly transparent, more cloudy material than                   control       35   (C) 500 ppm POAA only   Polypropylene   A white heavy filmed, faintly transparent, more cloudy                   material than control       41   (D) 5000 ppm POAA only   Polypropylene   A white filmy, faintly transparent, more cloudy material than                   control       47   CONTROL   Polypropylene   A dull gray, semi-transparent material       24   (A) 500 ppm POAA/Buffered   Polyvinyl   Slt. less shiny and slt. less dark gray material than control               Chloride       36   (C) 500 ppm POAA only   Polyvinyl   A dull med. gray material               Chloride       42   (D) 5000 ppm POAA only   Polyvinyl   A dull light to medium gray material               Chloride       48   CONTROL   Polyvinyl   A dark, shiny gray material               Chloride       25   (A) 500 ppm POAA/Buffered   ABS   A slt. dull, whiter material than control       31   (B) 5000 ppm POAA/Buffered   ABS   A slt. dull, whiter material than control       37   (C) 500 ppm POAA only   ABS   A slt. dull, much whiter white material than control       43   (D) 5000 ppm POAA only   ABS   A slt. dull bright white material       49   CONTROL   ABS   A slt. dull, vanilla white material       26   (A) 500 ppm POAA/Buffered   Polyacetal   A dull, cleaner white appearance than control       32   (B) 5000 ppm POAA/Buffered   Polyacetal   A dull, cleaner white appearance than control       38   (C) 500 ppm POAA only   Polyacetal   A dull, cleaner white appearance than control       44   (D) 5000 ppm POAA only   Polyacetal   A dull, cleaner white appearance than control       50   CONTROL   Polyacetal   A dull, dirty white material                    
         [0039]    [0039]                                                                                                                   PART IV: CORROSION - RUBBERS       Analytical - Observations       KX-6091 CORROSION STUDY       14 day Compatibility Test of 15 different materials tested against four different Test       Solutions at 50° C. with the test solutions are changed daily.                        Initial   Initial   Initial   Initial   Final   %   Final   %   Final   %   Final   %       Test       Material   Wt.   Ht.   Width   thick   Wt.   Weight   Ht.   Height   Width   Width   Thick   Thick       item   Test Solution   RUBBERS   (gms)   (inches)   (inches)   (inches)   (gms)   Change   (inches)   Change   (inches)   Change   (inches)   Change               51   (A) 500 ppm   Silicon   14.2724   2.930   0.928   0.254   14.2553   −0.1198   2.930   0.0000   0.933   0.5388   0.254   0.0000           POAA/           Buffered       56   (B) 5000   Silicone   15.5707   2.999   1.007   0.249   15.5665   −0.0270   2.995   −0.1334   1.008   0.0993   0.249   0.0000           ppm           POAA/           Buffered       61   (C) 500 ppm   Silicone   15.6958   3.013   0.995   0.252   15.7755   0.5078   3.019   0.1991   1.004   0.9045   0.252   0.0000           POAA only       66   (D) 5000   Silicone   15.1443   2.977   0.994   0.246   15.3760   1.5299   3.003   0.6734   1.005   1.1066   0.249   1.2195           ppm           POAA only       71   CONTROL   Silicone   15.6702   2.970   1.001   0.253   15.6417   −0.1819   2.970   0.0000   1.013   1.1988   0.254   0.3953       52   (A) 500 ppm   Butyl   1.9074   2.999   0.507   0.069   1.9852   4.0789   3.008   0.3001   0.507   0.0000   0.071   2.8986           POAA/           Buffered       57   (B) 5000   Butyl   1.9082   2.999   0.505   0.069   1.9263   0.9485   3.008   0.3001   0.505   0.0000   0.069   0.0000           ppm           POAA/           Buffered       62   (C) 500 ppm   Butyl   1.9026   2.996   0.505   0.068   2.0729   8.9509   3.017   0.7009   0.513   1.5842   0.075   10.2941           POAA only       67   (D) 5000   Butyl   1.9097   2.998   0.507   0.069   2.2216   16.3324   3.029   1.0340   0.494   −2.5841   0.078   13.0435           ppm           POAA only       72   CONTROL   Butyl   1.9001   2.998   0.507   0.069   1.8939   −0.3263   2.998   −0.0867   0.504   −0.5917   0.069   0.0000       53   (A) 500 ppm   Vison   23.3725   3.057   1.031   0.248   23.4407   0.2918   3.071   0.4580   1.033   0.1940   0.248   0.0000           POAA/           Buffered       58   (B) 5000   Vison   21.3847   2.984   1.014   0.237   21.4843   0.5598   2.998   0.4692   1.025   1.0848   0.238   0.4219           ppm           POAA/           Buffered       68   (D) 5000   Vison   22.4157   2.964   1.012   0.251   23.7728   6.0542   3.064   3.3738   1.053   4.0514   0.260   3.5857           ppm           POAA only       73   CONTROL   Vison   22.0694   2.988   1.012   0.244   22.0584   −0.0498   2.991   0.1004   1.012   0.0000   0.244   0.0000       54   (A) 500 ppm   EPDM   17.0399   3.042   1.005   0.277   17.1763   0.8005   3.053   0.3616   1.009   0.3980   0.285   2.8881           POAA/           Buffered       59   (B) 5000   EPDM   16.9577   3.033   1.006   0.278   17.2265   1.5851   3.036   0.0989   1.012   0.5964   0.285   2.5180           ppm           POAA/           Buffered       64   (C) 500 ppm   EPDM   16.9824   3.059   1.015   0.275   16.9653   −0.1007   3.068   0.2942   1.012   −0.2956   0.282   2.5455           POAA only       69   (D) 5000   EPDM   17.4875   2.985   1.072   0.274   17.9757   2.7917   3.020   1.1725   1.079   0.6530   0.284   3.6496           ppm           POAA only       74   CONTROL   EPDM   16.7254   2.964   1.016   0.278   16.6918   −0.2009   2.959   −0.1687   1.015   −0.0984   0.278   0.0000       55   (A) 500 ppm   BUNA N   15.8678   2.960   1.006   0.242   16.3169   2.8303   2.970   0.3378   1.012   0.5964   0.247   2.0661           POAA/           Buffered       80   (B) 5000   BUNA N   15.9576   2.980   1.020   0.240   16.4275   2.9447   2.989   0.3020   1.019   −0.0980   0.246   2.5000           ppm           POAA/           Buffered       85   (C) 500 ppm   BUNA N   16.2737   2.977   1.016   0.246   18.9478   4.1423   2.992   0.5039   1.024   0.7874   0.259   5.2846           POAA only       70   (D) 5000   BUNA N   15.8516   2.956   1.014   0.242   16.5043   4.1176   2.956   0.0000   1.029   1.4793   0.264   9.0909           ppm           POAA only       75   CONTROL   BUNA N   16.0735   2.936   1.107   0.247   16.0328   −0.2532   2.937   0.0341   1.014   −0.2950   0.247   0.0000                    Test       Material           item   Test Solution   RUBBERS   Visual Observations               51   (A) 500 ppm POAA/Buffered   Silicone   A dull, med. - dark orange material similar to                   control       56   (B) 5000 ppm POAA/Buffered   Silicone   A dull, med. - dark orange material similar to                   Control       61   (C) 500 ppm POAA only   Silicone   A dull, med. - dark orange material similar to                   Control       66   (D) 5000 ppm POAA only   Silicone   A dull, med. - dark orange material similar to                   Control       71   CONTROL   Silicone   A dull, med. - dark orange material       52   (A) 500 ppm POAA/Buffered   Butyl   A dull black material with slt. tacky, slt. rough                   surface that stuck to drying surface resulting in loss                   of material       57   (B) 5000 ppm POAA/Buffered   Butyl   A dull black material with very slt. tacky, smooth                   surface       62   (C) 500 ppm POAA only   Butyl   A black material with tacky, dull, rough surface                   that stuck to drying surface resulting in loss of                   material       67   (D) 5000 ppm POAA only   Butyl   A dull black material with very tacky, very rough,                   surface that stuck to drying surface resulting in loss                   of material       53   (A) 500 ppm POAA/Buffered   Vison   A dull, charcoal black material with smooth surface       58   (B) 5000 ppm POAA/Buffered   Vison   A dull, charcoal black material with smooth surface       63   (C) 500 ppm POAA only   Vison   A dull, charcoal black material with slt. rough                   surface       68   (D) 5000 ppm POAA only   Vison   A dull, charcoal black material with slt. rough                   surface       73   CONTROL   Vison   A dull, charcoal black material with smooth surface       54   (A) 500 ppm POAA/Buffered   EPDM   A dull, black material with slt. rough surface       59   (B) 5000 ppm POAA/Buffered   EPDM   A dull, black material with slt. blistered surface       64   (C) 500 ppm POAA only   EPDM   A dull, black material with slt. rough surface       69   (D) 5000 ppm POAA only   EPDM   A dull black material with slt. rough surface                   containing a large blister       74   CONTROL   EPDM   A dull, black material with smooth surface       55   (A) 500 ppm POAA/Buffered   BUNA N   A dull, (darker than control) black material with slt.                   rough surface       60   (B) 5000 ppm POAA/Buffered   BUNA N   A dark black material with very slt. shiny, fairly                   smooth surface       65   (C) 500 ppm POAA only   BUNA N   A dark black material with very slt. shiny, slt.                   blistered surface       70   (D) 5000 ppm POAA only   BUNA N   A dark black material with very slt. shiny, blistered                   surface       75   CONTROL   BUNA N   A dull, grayish black material with smooth surface                    
         [0040]    I. Tuberculocidal Efficacy—US Method  
         [0041]    The peracetic acid product was tested against  Mycobacterium bovis  (bCG) using the AOAC Confirmatory Test with product concentrations as listed below. The product was diluted in buffer to achieve the pH 6 prior to test. The diluent tested was either tap or distilled water. Test exposure time was 10 minutes. A result of ten no growth tubes per ten tubes tested is required for a passing result Conclusion: successful tuberculocidal results were achieved at product concentrations as low as 1000 ppm POAA.  
                                                       Number of no growth tubes/           Product Concentration a     number of tubes tested b                             1000 ppm POAA   10/10 - pass           2000 ppm POAA   10/10 - pass           3000 ppm POAA   10/10 - pass           4000 ppm POAA   10/10 - pass           5000 ppm POAA   10/10 - pass                                              
 
         [0042]    II. Suspension Test—Olympus Method  
         [0043]    We have completed the suspension test as requested with the Olympus procedure versus  Bacillus subtilis.  The product was diluted in buffer to achieve the pH 6 prior to test The diluent tested was tap water. Test exposure times are listed below. The data are represented as log reduction of bacterial numbers. Note: the spores were counted after the heat shock treatment, although the test was conducted on a non-heat treated bacterial suspension. Conclusion significant log reductions in microbial numbers were achieved within 10 minutes using 500 ppm POAA. Additional product concentration or exposure time did not increase the efficacy of the product.  
                                                                   Bacillus subtilis  Log Reduction at 20° C.           (ppm POAA)                            1500 ppm   2000 ppm       Exposure time               (Henkel-Ecolab   (Ecolab test       (minutes)   250 ppm   500 ppm   1000 ppm   test only)   only)                5 minutes   4.55   6.13   9.48   7.70   9.78       10 minutes   7.98   9.78   9.78   7.68   9.78       20 minutes   9.48   9.78   9.78   7.71   9.78       60 minutes   9.48   9.78   9.78   7.74   9.78       Neutralization control                    0.10 A         Total Inoculum               3.4 × 10 5  cfu/ml   6.0 × 10 9  cfu/ml       Spore Inoculum               9.0 × 10 6  cfu/ml   3.3 × 10 5  cfu/ml                          
 
         [0044]    III. Carrier Test—Olympus Method  
         [0045]    We have completed the carrier test as requested using the Olympus procedure versus  Bacillus subtilis  and  Mycobacterium terrae.  The product was diluted in buffer to achieve the pH 6 prior to test. The diluent tested was tap water. Test exposure times are listed below. Note: the spores were counted after the heat shock treatment, although the test was conducted on a non-heat treated bacterial suspensions. Conclusion: successful results achieved using 250 ppm POAA within five minutes exposure against both  subtilis  and  Mycobacterium terrae.  Additional product concentration or exposure time did not increase the efficacy of the product.  
                                                                                                                                                                                                                                         250 ppm   1000 ppm   2500 ppm   5000 ppm            Exposure time   CARRIER A             CARRIER           CARRIER           CARRIER               (minutes)   RESULTS   A B     B C     RESULTS   A   B   RESULTS   A   B   RESULTS   A   B                          Bacillus subtilis  at 20° C.           (ppm POAA)             0 minutes                                       0/2   2.3 × 10 4     1.9 × 10 4          5 minutes   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1       10 minutes   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1       20 minutes   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1       60 minutes   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1                          Mycobacterium terrae  at 20° C.           (ppm POAA)             0 minutes                                       0/2   3.2 × 10 4     2.1 × 10 4          5 minutes   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1       10 minutes   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1       20 minutes   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1       60 minutes   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1   2/2   &lt;1   &lt;1                                                  
 
         [0046]    IV. Sporicidal Efficacy—US Method  
         [0047]    The peracetic add product was tested against  Clostridium sporogenes  using the AOAC Spodcidal Activity of Disinfectants Test with product concentrations as listed below. The product was diluted in buffer to achieve the pH 6 prior to test The diluent tested was tap water. Test exposure time was 3, 4 or 6 hours. A result of twenty no growth tubes per twenty tubes tested is required for a passing result. Conclusion: successful results were achieved at 5000 ppm POAA with an exposure time of 6 hours.  
                                                                 Number of no growth tubes/       Product   Exposure   number of tubes tested b              Concentration a     Time   Primary Subculture   Secondary Subculture               4000 ppm   3 hours   20/20    0/20       POAA   4 hours   20/20    1/20           6 hours   19/20   20/20       5000 ppm   3 hours   19/20    6/20       POAA   4 hours   20/20   17/20           6 hours   20/20   20/20       7000 ppm   3 hours   20/20   10/20       POAA   4 hours   20/20   11/20           6 hours   20/20   20/20                                  
 
         [0048]    Objective:  
         [0049]    The objective of this analysis was to evaluate the effect of hydrogen peroxide and acetic acid concentration on the sporicidal efficacy of 150 ppm peracetic acid at 40° C.  
         [0050]    Test Method:  
         [0051]    Ecolab Microbiological Services SOP CB02104;  Rate of Kill Antimicrobial Efficacy.  Following exposure to the formula and subsequent neutralization, spores were heat shocked for 13 minutes at 80° C. before plating.  
         [0052]    Method Parameters:  
                                                     Chemical Properties of Each Test Formula                Theoretical   Theoretical   Theoretical           Formula   ppm POAA   ppm H 2 O 2     ppm Acetic Acid   pH               A   150    31   159   3.75       B   150    31   309   3.67       C   150   275   159   3.75       D   150   275   309   3.68       E   150   529   159   3.77       F   150   529   309   3.68                       #sheet attached to this report for preparation information. Since chemical analyses of solutions prepared exactly like those prepared for this study were done previously, and concentrations were found to be accurate, additional        #chemical analysis for this study was not perfomed (see MSR #960351, J. Hilgren).                                                           
 
         [0053]    Results:  
                                                                                               Inoculum Numbers                Inoculum Test Replicate (CFU/mL)   Average            Organism   1   2   3   (CFU/mL)                 B. cereus  Spores   30 × 10 6     26 × 10 6     26 × 10 6     2.7 × 10 7                      Reduction of  B. cereus  Spores at 40° C.                Exposure Time               Formula   (hours)   Survivors (CFU/mL)   Log Reduction               A   0.5   &lt;1.0 × 10 1     &gt;6.43       Low Acetic,   1.0   &lt;1.0 × 10 1     &gt;6.43       Low H 2 O 2     1.5   &lt;1.0 × 10 1     &gt;6.43           2.0   &lt;1.0 × 10 1     &gt;6.43           2.5   &lt;1.0 × 10 1     &gt;6.43           3.0   &lt;1.0 × 10 1     &gt;6.43           3.5   &lt;1.0 × 10 1     &gt;6.43       B   0.5   &lt;1.0 × 10 1     &gt;6.43       High Acetic,   1.0   &lt;1.0 × 10 1     &gt;6.43       Low H 2 O 2     1.5   &lt;1.0 × 10 1     &gt;6.43           2.0   &lt;1.0 × 10 1     &gt;6.43           2.5   &lt;1.0 × 10 1     &gt;6.43           3.0   &lt;1.0 × 10 1     &gt;6.43           3.5   &lt;1.0 × 10 1     &gt;6.43       C   0.5     1.7 × 10 7     0.20       Low Acetic,   1.0     6.0 × 10 6     0.65       Medium H 2 O 2     1.5     2.5 × 10 6     1.03           2.0     9.0 × 10 5     1.48           2.5     2.1 × 10 5     2.11           3.0     6.0 × 10 4     2.65           3.5     1.5 × 10 4     3.26       D   0.5     1.5 × 10 7     0.26       High Acetic,   1.0     4.9 × 10 6     0.74       Medium H 2 O 2     1.5     2.2 × 10 6     1.09           2.0     4.6 × 10 5     1.77           2.5     1.2 × 10 5     2.35           3.0     3.1 × 10 4     2.94           3.5     1.1 × 10 4     3.39       E   0.5     1.5 × 10 7     0.26       Low Acetic,   1.0     5.1 × 10 6     0.72       High H 2 O 2     1.5     1.4 × 10 6     1.29           2.0     3.1 × 10 5     1.94           2.5     3.4 × 10 4     2.90           3.0     4.0 × 10 3     3.83           3.5     5.6 × 10 2     4.68       F   0.5     1.4 × 10 7     0.29       High Acetic,   1.0     4.7 × 10 6     0.76       High H 2 O 2     1.5     1.7 × 10 6     1.20           2.0     4.3 × 10 5     1.80           2.5     3.3 × 10 4     2.91           3.0     5.0 × 10 3     3.73           3.5     8.1 × 10 2     4.52                  
 
         [0054]    [0054]           
       CONCLUSIONS  
       [0055]    The sporicidal activity of 150 ppm POAA at 40° C. against  Bacillus cereus  spores was most effective when in the presence of relatively low concentrations of H 2 O 2  (≈30 ppm as in Formulas A and B). Reduced  B. cereus  sporicidal efficacy was observed using POAA with the medium and high concentrations of H 2 O 2  (≈160 and 300 ppm as in Formulas C through F).  
         [0056]    Objective:  
         [0057]    The objective of this analysis was to evaluate the effect of hydrogen peroxide and acetic acid concentration on the sporicidal efficacy of 150 ppm peracetic acid at 60° C.  
         [0058]    Test Method:  
         [0059]    Ecolab Microbiological Services SOP CB02104;  Rate of Kill Antimicrobial Efficacy.  Following exposure to the formula and subsequent neutralization, spores were heat shocked for 13 minutes at 80° C. before plating.  
         [0060]    Method Parameters:  
                                                               Analytical Chemistry Results - A&amp;P Methods 9403201, 9600300                Formula Properties           (≈ 2 Hours Post Preparation/After 40 min. at 60° C.)            Formula   ppm POAA   ppm H 2 O 2     ppm Acetic Acid   pH               A   147/144   31/33   174/166   3.76/3.67       B   145/144   33/37   346/346   3.71/3.55       C   151/148   277/281   141/143   3.79/3.69       D   151/151   283/280   301/291   3.70/3.60       E   157/154   526/514   136/148   3.81/3.71       F   160/159    533/240*   293/324   3.71/3.62                               #sheet attached to this report for theoretical concentrations and preparation information.                                                           
 
         [0061]    [0061]                                                                   Inoculum Numbers                Inoculum Test Replicate (CFU/mL)   Average            Organism   1   2   3   (CFU/mL)                 B. cereus  Spores   28 × 10 6     22 × 10 6     29 × 10 6     2.6 × 10 7                      
         [0062]    [0062]                                                                   Reduction of  B. cereus  Spores at 60° C.                Exposure Time               Formula   (min.)   Survivors (CFU/mL)   Log Reduction                    A   10   &lt;1.0 × 10 1     &gt;6.41       Low Acetic,   15   &lt;1.0 × 10 1     &gt;6.41       Low H 2 O 2     20   &lt;1.0 × 10 1     &gt;6.41           25   &lt;1.0 × 10 1     &gt;6.41           30   &lt;1.0 × 10 1     &gt;6.41           40   &lt;1.0 × 10 1     &gt;6.41       B   10   &lt;1.0 × 10 1     &gt;6.41       High Acetic,   15   &lt;1.0 × 10 1     &gt;6.41       Low H 2 O 2     20   &lt;1.0 × 10 1     &gt;6.41           25   &lt;1.0 × 10 1     &gt;6.41           30   &lt;1.0 × 10 1     &gt;6.41           40   &lt;1.0 × 10 1     &gt;6.41       C   10     4.1 × 10 4     2.80       Low Acetic,   15     2.0 × 10 2     5.11       Medium H 2 O 2     20   &lt;1.0 × 10 1     &gt;6.41           25   &lt;1.0 × 10 1     &gt;6.41           30   &lt;1.0 × 10 1     &gt;6.41           40   &lt;1.0 × 10 1     &gt;6.41       D   10     2.6 × 10 4     3.00       High Acetic,   15     7.0 × 10 1     5.57       Medium H 2 O 2     20   &lt;1.0 × 10 1     &gt;6.41           25   &lt;1.0 × 10 1     &gt;6.41           30   &lt;1.0 × 10 1     &gt;6.41           40   &lt;1.0 × 10 1     &gt;6.41       E   10     2.4 × 10 4     3.03       Low Acetic,   15     2.4 × 10 2     5.03       High H 2 O 2     20   &lt;1.0 × 10 1     &gt;6.41           25   &lt;1.0 × 10 1     &gt;6.41           30   &lt;1.0 × 10 1     &gt;6.41           40   &lt;1.0 × 10 1     &gt;6.41       F   10     1.1 × 10 4     3.37       High Acetic,   15     7.0 × 10 1     5.57       High H 2 O 2     20   &lt;1.0 × 10 1     &gt;6.41           25   &lt;1.0 × 10 1     &gt;6.41           30   &lt;1.0 × 10 1     &gt;6.41           40   &lt;1.0 × 10 1     &gt;6.41                    
         [0063]    [0063]           
       CONCLUSIONS  
       [0064]    The sporicidal activity of 150 ppm POAA at 60° C. against  Bacillus cereus  spores was most effective when in the presence of relatively low concentrations of H 2 O 2  (a 30 ppm as in Formulas A and B). A decrease in  B. cereus  sporicidal efficacy was observed using the medium and high concentrations of H 2 O 2  (a 160 and 300 ppm as in Formulas C through F).  
         [0065]    Further testing using Formulas A-F will be conducted at 20° C. to determine the effect of H 2 O 2  and acetic acid concentration on sporicidal efficacy of POAA at low temperature.  
         [0066]    Objective:  
         [0067]    The objective of this analysis was to evaluate the effect of hydrogen peroxides octanoic acid and peroctanoic acid concentration on the sporicidal efficacy of 150 ppm peracetic acid at 40° C.  
         [0068]    Test Method: Ecolab Microbiological Services SOP CB02104;  Rate of Kill Antimicrobial Efficacy.  Following exposure to the formula and subsequent neutralization, spores were heat shocked for 13 minutes at 80° C. before plating. Method Parameters:  
                                                                                           Chemical Properties of Each Test Formula                Theoretical   Theoretical   Theoretical   Theoretical   Theoretical           Formula   ppm POAA   ppm H 2 O 2     ppm AA   ppm POOA   ppm OA   pH                    1   149   36   282   12   39   3.65       2   149   529   282   12   39   3.62       3   149   36   282   50   39   3.64       4   149   529   282   50   39   3.63       5   149   36   282   12   138   3.64       6   149   529   282   12   138   3.63       7   149   36   282   50   138   3.64       8   149   529   282   50   138   3.65                       # Prior to this study, chemical analyses of formulas exactly like those used for this study were conducted to determine if ingredient concentrations were close to theoretical and if they were stable over the duration of the efficacy test. Results showed ingredient concentrations to correlate with theoretical and to be stable.                                                           
 
         [0069]    [0069]                                                                                               Inoculum Numbers                Inoculum Test Replicate (CFU/mL)   Average            Organism   1   2   3   (CFU/mL)                 B. cereus  Spores   56 × 10 6     42 × 10 6     35 × 10 6     4.4 × 10 7                      Reduction of  B. cereus  Spores at 40° C.                Exposure Time               Formula   (minutes)   Survivors (CFU/mL)   Log Reduction               1   5     3.0 × 10 1     6.17       Low H 2 O 2 ,   10   &lt;1.0 × 10 1     &gt;6.64       Low POOA,   15   &lt;1.0 × 10 1     &gt;6.64       Low OA   20   &lt;1.0 × 10 1     &gt;6.64           25   &lt;1.0 × 10 1     &gt;6.64           30   &lt;1.0 × 10 1     &gt;6.64       2   5     6.4 × 10 6     0.84       High H 2 O 2 ,   10     4.3 × 10 6     1.01       Low POOA,   15     1.8 × 10 6     1.39       Low OA   20     4.0 × 10 5     2.04           25     1.2 × 10 5     2.56           30     8.1 × 10 4     2.73       3   5   &lt;1.0 × 10 1     &gt;6.64       Low H 2 O 2 ,   10   &lt;1.0 × 10 1     &gt;6.64       High POOA,   15   &lt;1.0 × 10 1     &gt;6.64       Low OA   20   &lt;1.0 × 10 1     &gt;6.64           25   &lt;1.0 × 10 1     &gt;6.64           30   &lt;1.0 × 10 1     &gt;6.64       4   5     3.4 × 10 5     2.11       High H 2 O 2 ,   10     1.6 × 10 4     3.44       High POOA,   15     1.9 × 10 3     4.36       Low OA   20     3.0 × 10 1     6.17           25   &lt;1.0 × 10 1     &gt;6.64           30   &lt;1.0 × 10 1     &gt;6.64       5   5   &lt;1.0 × 10 1     &gt;6.64       Low H 2 O 2 ,   10   &lt;1.0 × 10 1     &gt;6.64       Low POOA,   15   &lt;1.0 × 10 1     &gt;6.64       High OA   20   &lt;1.0 × 10 1     &gt;6.64           25   &lt;1.0 × 10 1     &gt;6.64           30   &lt;1.0 × 10 1     &gt;6.64       6   5     4.4 × 10 6     1.00       High H 2 O 2 ,   10     4.1 × 10 5     2.03       Low POOA,   15     7.7 × 10 4     2.76       High OA   20     5.3 × 10 4     2.92           25     1.4 × 10 4     3.50           30     5.8 × 10 3     3.88       7   5   &lt;1.0 × 10 1     &gt;6.64       Low H 2 O 2 ,   10   &lt;1.0 × 10 1     &gt;6.64       High POOA,   15   &lt;1.0 × 10 1     &gt;6.64       High OA   20   &lt;1.0 × 10 1     &gt;6.64           25   &lt;1.0 × 10 1     &gt;6.64           30   &lt;1.0 × 10 1     &gt;6.64       8   5     1.2 × 10 5     2.56       High H 2 O 2 ,   10     2.0 × 10 3     4.34       High POOA,   15     4.0 × 10 1     6.04       High OA   20   &lt;1.0 × 10 1     &gt;6.64           25   &lt;1.0 × 10 1     &gt;6.64           30   &lt;1.0 × 10 1     &gt;6.64                    
       CONCLUSIONS  
       [0070]    Effect of H 2 O 2 :  
         [0071]    The sporicidal activity of 150 ppm POAA at 400C against  Bacillus cereus  spores was most effective when in the presence of relatively low concentrations of H 2 O 2  (=36 ppm as in Formulas 1, 3, 5 and 7). Reduced  B. cereus  sporicidal efficacy was observed using POAA with the higher concentrations of H 2 O 2  (=529 ppm as in Formulas 2, 4, 6 and 8).  
         [0072]    Effects of Octanoic and Peroctanoic Acid:  
         [0073]    The sporicidal activity of 150 ppm POAA at 40° C. against  Bacillus cereus  spores increased when the concentrations of octanoic or peroetanoic acid increased. This phenomenon was clearly evident in formulas containing the high concentrations of H 2 O 2  (formulas 2, 4, 6 and 8).  
         [0074]    On a weight basis, peroctanoic acid had a greater effect on the sporicidal efficacy of 150 ppm POAA against  B. cereus  than octanoic acid. An increase of 38 ppm POOA resulted in a greater log reduction of  B. cereus  spores than an increase of 99 ppm octanoic acid. An additive effect was observed when POOA and octanoic acid were combined.