1. Microbial Risk Assessment for Benefit Estimation of Antimicrobial Consumer Handproducts Charles N. Haas Drexel University Acknowledgment Mark Weir, Graduate Assistant

2. Qualifications & Disclaimer 20+ years of experience developing & applying microbial risk assessment Fellow, American Academy of Microbiology, Society for Risk Analysis, American Association for the Advancement of Sciences Work on antimicrobial hand products supported by SDA/CTFA

3. Conclusions Microbial risk assessment can be used to quantify the benefits of use of antimicrobial- containing consumer hand products For the scenario considered, use of such products resulted in reduction in median risk from a single exposure by a factor of 3 to a factor of 16 (depending on active ingredient)

4. Methods Health Care Personnel Hand Wash study data on various formulations of product with different organism strains Analyzed reduction (log N/N 0 ) to get distributions Performed Monte Carlo analyses in a defined scenario according to Haas et al. (Int. J. Hyg. Env. Hlth, in press)

5. Sources of Data SDA/CTFA contractor compiled data from company records ASTM E11-74 from a single contract laboratory Summarized inactivation ratios transmitted to us for analysis

6. Studies in Current Data Set Active Ingredient E coliSerratiaStaph aureus chlorhexidine4361 alcohols28 no active (*) 21 triclocarban3123 triclosan17433 (*) information available from prior studies

7. Scenario Considered Handling ground beef containing E. coli –Beef --> hands From ground beef prevalence and transfer studies –Hand decontamination by washing From current data –Transference from hand to mouth From transference studies –Dose-response from ingested E. coli Previously assessed from human feeding trials

8. Single Event Risk Reduction - Summary

9. Conclusions Restated Microbial risk assessment can be used to quantify the benefits of use of antimicrobial- containing consumer hand products For the scenario considered, use of such products resulted in reduction in median risk from a single exposure by a factor of 3 to a factor of 16 (depending on active ingredient)