1. PREVENTION Ag Silver Composite Materials: EH & S Considerations

2. © 2012 NanoHorizons Inc.CONFIDENTIAL Ancient Times Egyptians used in drinking water Roman soldiers used in wound healing Chinese used in eating utensils 1880 - Crede's prophylaxis for infant eye drops 1920's - Over 3 million prescriptions written annually for nanoscale silver-containing (colloidal silver) medications. 1960's - Silver compounds begin to be used in burn wards 1980's - Silver ion based additive for plastics become widespread 1990’s – Silver impregnated medical devices introduced 2000's – Polymer compatible silver additives developed Silver has a long history as a safe and effective antimicrobial Aqua-Precision

3. © 2012 NanoHorizons Inc.CONFIDENTIAL Encapsulation of silver particles Prevention Ag additives are delivered as a traditional ready-to-use powder. As produced, Prevention Ag is a composite powder, ie. particles encapsulated in a micron size polymer stabilizer Standard PPE (as listed in MSDS) is adequate. micron sized Prevention Ag powders encapsulated Prevention Ag particles Aqua-Precision

4. © 2012 NanoHorizons Inc.CONFIDENTIAL Air Quality Monitoring at The Prevention Ag manufacturing plant (2009, 2010) during manufacture and hopper loading showed silver levels at ~10% of the OSHA Permissible Exposure Limit (PEL) for General Industry (0.01 mg/m 3 TWA) and ~1% of the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) (0.1 mg/m 3 TWA) for Silver, Metal. In vivo studies 1 have confirmed that the longstanding 0.1 mg/m 3 NOEL for airborne silver compounds is adequate for silver. 1 Sung, et al. Subchronic Inhalation Toxicity of Silver and Silver Nanoparticles. TOXICOLOGICAL SCIENCES 108(2), 452–461 (2009). Exposure Monitoring Aqua-Precision

5. © 2012 NanoHorizons Inc.CONFIDENTIAL Cytotoxicity Method – MEM Elution ISO 10993 Part 5 1999 ed. Testing Org – Biochem S.A.S. Predosa, Italy Test Item – Silver Treated Rayon Absorbent (0.024% Ag/wt) Conclusions – No Measurable Cytotoxicity 24 Hour ResultsScore Positive Control4 Negative Control0 MEM Control0 MEM Extract0 48 Hour ResultsScore Positive Control4 Negative Control0 MEM Control0 MEM Extract0 Biocompatibility Testing Aqua-Precision

6. © 2012 NanoHorizons Inc.CONFIDENTIAL Dpm (mean+SD)Stimulation IndexStatistical Significance* Negative Control817 ± 309NA Test Article992 ± 3131.2No Positive Control10758 ± 211413.2Yes * p<0.05 as compared to negative control Biocompatibility Testing Sensitization Method – Test for Irritation and Delayed Type Hypersensitivity ISO 10993 Part 10 1999 ed. Testing Org – NAMSA, Northwood, OH Test Item – Polyform AS (50% Ag/wt), Prepared 20%/wt in DMSO Conclusion – No Significant Proliferation of Lymphocytes Aqua-Precision

7. © 2012 NanoHorizons Inc.CONFIDENTIAL Rabbit No.Obs.Dermal Reactions Days 1234567 58570 Intact ER ED 0000 0000 0000 0000 0000 0000 0000 58573 Intact ER ED 0000 0000 0000 0000 0000 0000 0000 58536 Intact ER ED 1010 1010 1010 0000 0000 0000 0000 58571 Abraded ER ED 0000 0000 0000 0000 0000 0000 0000 58535 Abraded ER ED 1010 1010 1010 1010 1010 0000 0000 ER = ErythemaED = Edema Biocompatibility Testing Dermal Toxicity Method – FHSA Dermal Toxicity Study 7, Day 16 CFR 1500 Testing Org – NAMSA, Northwood, OH Test Item – Polyform AS (50% Ag/wt), Administered at 2g/kg Conclusion - 2g/kg Dose Would not be Considered Toxic Aqua-Precision

8. © 2012 NanoHorizons Inc.CONFIDENTIAL Animal Number SexBody WeightClinical Obs. Days 1-7 Necroscopy Day 7 Day 0Day 7 6956Male243314Appeared NormalMacroscopically Normal 6957Male256328Appeared NormalMacroscopically Normal 6958Male263335Appeared NormalMacroscopically Normal 6959Male264347Appeared NormalMacroscopically Normal 6960Male250321Appeared NormalMacroscopically Normal Mean:255329 Biocompatibility Testing Oral Toxicity Method – FHSA Oral Toxicity Study 7, Day 16 CFR 1500 Testing Org – NAMSA, Northwood, OH Test Item – Polyform AS (50% Ag/wt) Dosed at 5g/Kg Body wt Conclusions – Would not be Considered Toxic at 5g/Kg Dose Aqua-Precision

9. © 2012 NanoHorizons Inc.CONFIDENTIAL Rabbit No. Gender Reaction24 Hours72 Hours IntactAbradedIntactAbraded 58519 Male Erythema0000 Edema0000 58523 Male Erythema0001 Edema0000 58524 Male Erythema0000 Edema0000 * Primary Irritation Index = 1/12 = 0.1 Biocompatibility Testing Skin Irritation Method – FHSA Skin Irritation Study 7, Day 16 CFR 1500 Testing Org – NAMSA, Northwood, OH Test Item – Polyform AS (50% Ag/wt), Prepared at 20%/wt in Water Aqua-Precision

10. © 2012 NanoHorizons Inc.CONFIDENTIAL Biocompatibility Testing Cytotoxicity & Microbial Toxicity Testing Org – Rice University & University of Duisburg-Essen Test Item – Silver Salts (Silver Acetate & Silver Nitrate) – Silver particles (<50 nm diameter) Conclusion – Biological activity not affected by silver particles – Antimicrobial properties are directly related to the Ag + release (like all other silver-based antimicrobials) Conc. of Silver ExaminedSilver AcetateSilver Particles 15 μg/mL98%96% 20 μg/mL43%85% 25 μg/mL0%70% Conc. of Viable Human Cells (relative to control) after exposure to different types of silver. Aqua-Precision

11. © 2012 NanoHorizons Inc.CONFIDENTIAL Raad, I., et al., Anti-adherence activity and antimicrobial durability of anti-infective- coated catheters against multidrug-resistant bacteria. J. Antimicrob. Chemother., 2008. 62(4): p. 746-750. Valappil, S.P., J.C. Knowles, and M. Wilson, Effect of silver-doped phosphate-based glasses on bacterial biofilm growth. Applied and Environmental Microbiology, 2008. 74(16): p. 5228-5230. Kollef, M.H., et al., Silver-Coated Endotracheal Tubes and Incidence of Ventilator- Associated Pneumonia: The NASCENT Randomized Trial. JAMA, 2008. 300(7): p. 805- 813. Weir, E., et al., The use of particles in anti-microbial materials and their characterization. Analyst, 2008. 133(7): p. 835-845. Roe, D., et al., Antimicrobial surface functionalization of plastic catheters by silver nanoparticles. J. Antimicrob. Chemother., 2008. 61(4): p. 869-876. Steven L. Percival, P.B.E.J.W., Assessing the effect of an antimicrobial wound dressing on biofilms. Wound Repair and Regeneration, 2008. 16(1): p. 52-57. Biocompatibility Testing Aqua-Precision