Waterborne Microbial Disease Strategy Stakeholder Meeting Summary
The Safe Drinking Water Act (SDWA) and the Clean Water Act (CWA)
address microbial contamination of the Nation's waters. The SDWA
enables regulation of contamination of finished drinking water and
protection of source waters. The CWA enables protection of surface
water for drinking water, recreational, and aquatic food source
uses. Programs under the two Acts have historically followed separate
paths using differing indicators of contamination and different
approaches. Concerns about future increases in microbial contamination
and the potential for emergence of new threats create a need to
consider a strategy for the future that unites the two programs.
Objectives of the strategy are to address all important sources
of contamination, anticipate emerging problems, and use program
and research activities efficiently to protect public health.
As the EPA strategy develops, it will have many stakeholders and
partners. An important part of the EPA strategy will be the cooperative
engagement of the programs and research of states, tribes, other
federal agencies and departments, and private entities.
The Office of Water recognizes the need for an integrated approach
and extension of the Agency's current programs to reduce the adverse
impacts of microbial contamination in our Nation's waters, whether
this contamination arises from naturally occurring sources, is introduced
through anthropogenic inputs from point source discharges or via
diffuse nonpoint source pollution, or is introduced intentionally
through acts of terrorism. In response to this need, the Office
of Water has developed the Draft Strategy for Waterborne Microbial
Disease - a multiyear strategy for reducing the risk of impacts
of microbial contamination in water through improved water quality
programs, risk communication, and scientific advancements.
The November 6, 2001, Waterborne Microbial Disease Strategy Stakeholders
Meeting had two major objectives. First, it introduced stakeholders
to the Office of Water Draft Strategy for Waterborne Microbial Disease.
Second, the meeting provided an opportunity for all interested parties
from government, private industry, academia, and the public sector
to voice their opinions and concerns related to the draft strategy
and suggested approaches to this issue.
Dr. Steve Schaub opened the meeting and introduced the EPA panel
members: Lisa Almodovar, Latisha Parker , and Dr. Rita Schoeny from
the Office of Water . Dr. Schaub then introduced Diane Regas, Deputy
Assistant Administrator of the Office of Water who gave the opening
remarks.
The next speaker, Dr. Rita Schoeny, Associate Director of the
Health and Environmental Criteria Division acknowledged the contributions
of several other EPA Offices in developing the strategy including:
the Office of Science and Technology; Office of Waste Management;
Office of Groundwater and Drinking Water; Office of Wetlands, Oceans,
and Watersheds; Office of Research and Development; and the EPA
Regional Offices. Dr. Schoeny then presented a description of the
problems, processes, goals, and approaches associated with the Agency's
development of a strategy for waterborne microbial disease control.
Following this, Jim Pendergast of the Office of Water's Water
Protection Task Force discussed protecting our Nation's drinking
water and wastewater systems from terrorists. This presentation
described the diversity of U.S. drinking water and wastewater systems
and the population profiles of the consumers they supplied, and
discussed potential threats from biological and chemical contaminants,
physical destruction, and cyber attacks. He also detailed responsibilities
for drinking water and wastewater preparedness and emergency response
procedures, and identified the specific responsibilities of the
EPA's Water Protection Task Force.
Dr. Mark Sobsey of the University of North Carolina at Chapel
Hill, next summarized ambient water quality criteria that included
a discussion of recreational water quality and health effects, and
various types of microbes and pathogens now detectable in water
that pose potential health threats. He also discussed microbial
indicators available to detect and characterize recreational water
quality, some of the problems with current indicators, and use of
a suite of indicators. Dr. Sobsey then addressed animal fecal contamination;
magnitude of manure production and treatment needs; animal manure
management systems and environmental impacts; some potential human
viral, bacterial, and parasitic pathogens in animals; and the problem
of antimicrobials and antibiotic-resistant bacteria in animal production.
Dr. Sobsey concluded his presentation with a discussion of information
on factors favoring waterborne and other transmission routes of
pathogens from agricultural animal wastes, ambient water quality
criteria and Total Maximum Daily Loads (TMDLs) for microbes, and
the need for a modern, risk-based approach in the strategy.
Dr. Isabelle Walls of the International Life Sciences Institute
(ILSI) then addressed microbial risk assessment and the microbial
paradigm used by ILSI. This risk assessment procedure includes a
systematic assessment of the nature and severity of the hazard,
problem formulation, and risk management steps. Using case study
results from Cryptosporidium parvum contamination in water, Dr.
Walls guided attendees step-by-step through a risk assessment using
the ILSI framework. Dr. Walls next profiled disease outbreaks associated
with U.S. drinking water contamination during 1997 and 1998 including
the etiologic agent, number of cases, deficiency in the treatment
system, and water source for the outbreaks. She also detailed procedures
for pathogen characterization and occurrence, exposure analysis,
host characterization, health effects, dose-response analysis, and
risk characterization. She described a conceptual schematic of health
effects assessment as well as pathogen characterization and occurrence,
and discussed effect of treatments, exposure analysis, and exposure
profile. Dr. Walls concluded by discussing human health including
host characterization, health effects, dose-response analysis, risk
characterization, and risk management and identified further research
needs.
Dr. Charles Noss of the Water Environment Research Foundation
then gave a presentation on contamination sources and discussed
what constitutes "safe" water, control strategy objectives for contamination
sources, and how the strategy should consider the needs of all stakeholders.
He also detailed pathogens, prevalence and disease, population issues
such as distribution and growth that create impacts on water use.
Additionally, he described U.S. patterns of groundwater and surface
water withdrawals, wastewater contamination sources, size of municipal
and onsite wastewater treatment facilities, wastewater reclamation,
stormwater runoff contamination, domestic animal sources, microbial
sources, and bacterial source tracking. He compared data from the
Atlas of American's Polluted Waters to show wide variability in
the number of river miles and coastal shoreline miles several pairs
of adjacent states reported impaired by pathogens and raised questions
about the accuracy of this information. He concluded by discussing
multiple stressors and risk, other things to consider, policy questions,
and the need for an integrated approach to the strategy.
The last presentation of the day was to be given by Dr. Charles
Gerba of the University of Arizona. However, since Dr. Gerba could
not attend, Dr. Mark Sobsey agreed to give a modified presentation
using both Dr. Gerba and his own slides. Dr. Sobsey detailed water
uses including domestic and industrial wastewater reuse, cooling
tower waters, ballast/boat discharges, and biosolids. He also described
special water use in hospitals, home water treatment units, potable
water treatment units, hot tubs and swimming pools. Current problems
with these uses include no uniform EPA standards, no risk-based
microbial standards, standard variability among states, little or
no guidance provided to local governments for standard setting,
and little or inconsistent monitoring and enforcement policies.
Other special considerations discussed with respect to the traditional
fecal indicators were fecal coliforms that will regrow in sewage
discharges, pulp mill wastes, gray water, sediments, biosolids,
and compost. Dr. Sobsey discussed several issues and needs that
should be addressed including; development of standards for non-fecal
waterborne pathogens, impacts on wildlife and wildlife impacts on
humans and human activities, and the impact of opportunistic pathogens
on both sensitive populations (e.g., infants and children, elderly,
immuno-compromised) and the general population. He concluded by
discussing the need to develop two types of indicators: one type
for treatment performance testing and one type for risk assessment,
and the need to develop criteria for the development and acceptance
of indicators including study design and data needs.
The stakeholders meeting was then open to questions and/or comments
from attendees about the strategy.
Closing remarks were presented by Dr. Rita Schoeny. She thanked
attendees for their participation and input to the developmental
process for the strategy.
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