200929 Quantitative Evaluation of Enterococci and Bacteroides Released by Adults and Toddlers in Marine Water

Tuesday, November 10, 2009: 4:48 PM

Samir Elmir, PhD PE , Environmental Health and Engineering, Miami-Dade County Health Department, Miami, FL
Tomoyuki Shibata, PhD , Ohhc, University of Miami, Key Biscayne, FL
Helena Solo-Gabriele, PhD , Ohhc, University of Miami, Key Biscayne, FL
Lora E. Fleming, MD, PhD , Department of Epidemiology & Public Health, University of Miami, Miller School of Medicine - OHH Center and NIOSH Research Group, Miami, FL
Lisa Plano, MD PhD , Ohhc, University of Miami, Key Biscayne, FL
Jonathan K. Kish, MPH , Ohhc, University of Miami, Key Biscayne, FL
Christopher Sinigalliano, PhD , Ohhc, University of Miami, Key Biscayne, FL
Maribeth Gidley, MD , Ohhc, University of Miami, Key Biscayne, FL
Traditionally the use of enterococci as fecal indicator bacteria (FIB) has been recommended by EPA for testing recreational marine water. Recent studies showed that bathers shed large numbers of enterococci in the water. Two separate studies were conducted to evaluate bather shedding for enterococci using membrane filter (MF), chromogenic substrate (CS), and quantitative polymerase chain reaction (qPCR)) and alternative FIB (e.g. bacteroides human markers via qPCR). The first study consisted of two sets of 10 adults who bathed together in a large pool (first two cycles were without beach sand exposure and the last two cycles were after sand exposures). The second study consisted of 14 sets of toddlers who bathed individually in a small pool which allowed for sand recovery. The numbers of estimated enterococci shed per adult ranged from 1.8x104 to 2.8x106 CFU, 1.9x103 to 4.5x106 MPN, and 3.8x105 to 5.5x106 GEU based on the MF, CS, and qPCR methods respectively. The estimated numbers of bacteroides human markers ranged from 1.8x104 to 1.3x106 for UCD and ranged from the below detection limit to 1.6x105 for HF8. The estimated amount of sand transported per toddler (n=14) into the water column after sand exposure was 86 g on average. Contributions of sands to the total enterococci (MF) shed per toddler was 3.7 4.4% on average. FIB shedding associated with beach sand could be small fraction during initial bathing but may have a significant role if bathers go to water repetitively after sand exposure.

Learning Objectives:
Evaluate numbers of bacteria shed per bather into the water column

Keywords: Environmental Health, Water Quality

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: principal Investigator
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.

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