Rapid Health-Based Method For Measuring
Microbia Indicators Of Recreational Water Quality
Kristen Brenner1, Rebecca Calderon2, Alfred Dufour1, Richard Haugland1, Elizabeth Sams2, Timothy Wade2, Shawn Siefring1, Michael Beach3
* 1U.S. Environmental Protection Agency (U. S. EPA)/Office of Research and Development (ORD)/National Exposure Research Laboratory (NERL)/Cincinnati, OH
* 2U.S. EPA/ORD/National Health and Environmental Effects Laboratory (NHEERLJ/Research Triangle Park, NC
* 3Centers for Disease Control and Prevention, Atlanta, GA
The Problem
Because the currently approved cultural methods for monitoring indicator bacteria in recreational water require
24 hours to produce results, the public may be exposed to potentially contaminated water before the water has
been identified as hazardous. This project was initiated to evaluate a rapid health-based method that could
obtain results the same day the water was collected. Use of a rapid method will allow beach managers and
public health officials to alert the public about potential health hazards in a timely manner (< 2 hours), thereby
reducing illness from recreational water use.
Research Methods
The beach epidemiological water study [National Epidemiological and Environmental Assessment of
Recreational (NEEAR) Water Study] consisted of (1) a water quality study of beach waters using a rapid,
same-day method, the Quantitative Polymerase Chain Reaction (QPCR), to determine Enterococcus
concentrations and (2) a swimmer health survey of illness outcomes after exposure of the swimmers to the water.
NEEAR Study Design
1. Two methods: QPCR and EPA Method 1600.
2. Four freshwater Great Lakes beaches.
3. Six sample locations (or nine at Huntington
Beach).
4. Three sample visits per day at 8 AM, 11 AM,
and 3 PM.
5. Saturdays, Sundays, and holidays.
6. 8-12 weekends per beach.
7. Concurrent survey of swimming-associated
illnesses at each beach.
8. Ancillary measurements for each water
sample, including beach, water, and weather
conditions, pH, and turbidity.
Canada
U] = ( ) { Omario/^V
1 Park Beach \ Qllio i "
Beach Sites
The NEEAR Water Study was conducted in 2003 and 2004 at four
freshwater Great Lakes beaches that were influenced by point sources
of wastewater.
1. West Beach, Indiana Dunes National Lakeshore, Porter, Indiana.
2. Huntington Beach, Bay Village, Ohio.
3. Washington Park Beach, Michigan City, Indiana.
4. Silver Beach, St. Joseph, Michigan.
O 2003 Beach Sites
4 2004 Beach Sites
1. Water Quality Study and Rapid Method Evaluation (NERL)
Water Sample Collection:
Six water samples were collected three times a day at all
beaches, except Huntington Beach, along each of three
transects perpendicular to the beach shoreline, one in
waist-high water {i.e., 1 meter deep) and one in shin-high
water {i.e., 0.3 meter deep) (See Figure 1.), for a total of 18
samples per day. Because the rock piers/jetties at Hunting-
ton Beach prevented free circulation of water, three addi-
tional shin-high samples (9 samples three times a day, for a
total of 27 samples per day) were collected at each visit
using a modified sampling scheme to properly characterize
the beach.
Figure 1. Water Sampling Protocol
• Quantitative Polymerase Chain Reaction (QPCR) for
the Same-Day (< 2 hours) Detection of Enterococci:
o = sampling location
Microbiological Methods:
' USEPA Method 1600-
The EPA-Approved Membrane
Filter Method for the Detection of
Enterococci\r\ Recreational Water:
Separate/denature strands
uiiwi
:h 2 primers and probe.
Taq polymerase attaches
~ DNA replicates, and probe is
1DDDB cleaved and degraded.
Instrument detects free
222 fluorescent reporter molecule,
and DNA elongates
|r>
Key | Attached Fluorescent Reporter Molecule
I Fluorescence Quencher (when attached)
I Free Fluorescent Reporter Molecule
US EPA Method 1600
2. Swimmer Health Survey (NHEERL)
Swimmer Health Survey Outcomes: Definitions:
Gastrointestinal Illness (GD - defined as any of the following:
a. Diarrhea - 3 or more loose stools in a 24-hour period.
b. Vomiting, nausea, and stomachache.
c. Impact on activity and either nausea or stomachache.
Upper Respiratory Illness CURD - defined as any two of the following:
sore throat, cough, runny nose, cold, fever.
Skin rash-
Eve ailment - eye infection or watery eye.
Earache-
Swimmer - a person who immersed his/her body
in the water with or without head immersion.
Non-Swimmer - a person who did not wade, swim
or play in the water.
Beach Interview • Part A
Enrollment Data Collected at participant location on beach
Beach Interview • Part B
Exposure Data Collected as participants leave beach
Phone Interview 10-12 days later
Health Data (Illness since swimming at beach)
Results
1. Results from the QPCR method were detected by the Smart Cycler Instrument (Cepheid) in
"real-time" (i.e., in < 2 hours).
2. Enterococci concentrations, obtained using the QPCR method, were significantly correlated with
swimming-associated gastroenteritis (i.e., As the concentrations of Enterococci increased, the risk of
gastroenteritis also increased.) (See Figure 2.).
3. Swimmers experienced more gastrointestinal illness, rashes, and earaches than non-swimmers.
4. The incidence of gastrointestinal illness was higher in children than in adults.
5. The 8 AM water sample analyses were predictive of illness the same day.
Figure 2. Swimming-Associated Gastrointestinal Illness and
Enterococcus exposure (All participants)
Enterococcus QPCR Cell Equivalents Daily Geometric Mean
Conclusions
Use of the QPCR method, which is capable of
producing "real time" results in < 2 hours, will
allow beach managers and public health offi-
cials to alert the public in a timely manner
about potential health hazards at Great Lakes
beaches, thereby reducing waterborne illness.
The data from this research study will be used
by the U. S. EPA Office of Water in their
efforts to provide new health-based criteria and
guidelines for recreational water quality.
Although this work was reviewed by EPA and approved for presentation, it way
not necessarily reflect Agency policy. Mention of trade names or commercial
epascienceforum
Your Health • Your Environment • Your Future
------- |