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Biosolids - Publications
March 25, 1996

To Interested Parties:

The Water Science and Technology Board (WSTB) of the National Research Council/National Academy of Sciences
recently issued an important new report,
Use of Reclaimed Water and Sludge in Food Crop Production

Robert Perciasepe, Assistant Administrator, states,  "It provides an independent assessment of the risks associated
with these practices and provides recommendations to improve these recycling practices and their acceptance."

Albert Page, University of California, Riverside, Committee Chair states, "The committee was not constituted to conduct
an independent risk assessment of possible health effects, but instead to review the method and procedures used by
EPA in its
extensive risk assessment, which was the basis for the Part 503 Sludge Rule."

Preface -- Use of Reclaimed Water and Sludge in Food Crop Production

In early 1993, the U.S. Environmental Protection Agency's (EPA) Office of Wastewater
Compliance and Enforcement suggested to the National Research Council's Water Science and
Technology Board (WSTB) that it should consider undertaking a study of public health and public
perception issues associated with the use of treated municipal wastewater and sludge in the production
of crops for human consumption. At the time, EPA was just finalizing the Part 503 Sludge Rule,
Standards for the Use or Disposal of Sewage Sludge, and one of the major implementation concerns
was with the food processing industry's reluctance to accept the practice. When EPA first promulgated
criteria for land application of municipal wastewater sludges to cropland in 1979, some food
processors questioned the safety of selling food crops grown on sludge-amended soils and their
liability. In response, the principal federal agencies involved—EPA, the U.S. Food and Drug
Administration (FDA), and the U.S. Department of Agriculture (USDA)—developed a Joint
Statement of Federal Policy in 1981 to assure that current high standards of food quality would not be
compromised by the use of high quality sludges and proper management practices. Nevertheless, the
food processing industry remains concerned about safety and market acceptability, and at least one
company has adopted an official policy that bans the purchase of any crops grown on fields receiving
municipal sewage sludge or treated municipal wastewater. With the issuance of the Part 503 Sludge
Rule in 1993, public concerns with a number of technical, regulatory, and environmental issues have
surfaced. Because cropland application of both sludge and wastewater represent important
management options, municipal wastewater management officials have a vital interest in the feasibility
of these practices.

Therefore, in mid-1993, WSTB formed a committee representing diverse expertise and
perspectives to conduct an independent study of the safety and practicality of the use of these materials
for the production of crops for human consumption. The study sought to review (1) the historical
development, rationale, and scope of the practice of treating municipal wastewater and sludge in the
United States; (2) wastewater treatment technologies and procedures for agricultural use of these
materials; (3) effects on soils, crop production, and ground water; (4) public health concerns about
microbiological agents and toxic chemicals; (5) existing regulations

viii Preface

and guidelines; and (6) economic, liability, and institutional issues. The committee based its re-view on
existing published literature and discussions with experts in the field. The committee was not
constituted to conduct an independent risk assessment of possible health effects, but instead to review
the method and procedures used by EPA in its extensive risk assessment, which was the basis for the
Part 503 Sludge Rule.

The committee met five times over a 17-month period including field visits to the Irvine Ranch
Water District in California, the CONSERV II Water Reclamation Program of Orange County and
Orlando, Florida, and the Disney World, Florida reuse programs. The committee also held a one-day
workshop at Rutgers University in New Brunswick, New Jersey to hear from researchers, public
interest groups, farm credit bureaus, farmers, and state and city planners on land application of
municipal sludge in the Northeast.

The committee focused primarily on the issues surrounding the use of treated municipal
wastewater effluents and treated sludge in food crop production, concentrating on the uptake of
chemical constituents and pathogens by food crops. The study did not include an investigation of what
happens after the crops are harvested (e.g., processing of food products). Further, the committee was
not constituted to evaluate site-specific implementation of wastewater effluent and sludge reuse
projects, or to compare the relative merits and risks of various other forms of disposal or beneficial
uses. However, the committee recognized that in addition to the safety and practicality of using these
materials on food crops, there are many implementation issues involved with the agricultural use of
municipal wastewater and sludge including the degree to which the regulations are implemented and
enforced, the public confidence in local reuse programs, local nuisance and traffic problems,
environmental and product liability issues, and overall public perceptions. In several of these areas, this
report notes particular findings that should receive the attention of federal, state, and local authorities
responsible for implementing reuse projects.

It is hoped that this report will be particularly useful to food processors, states, and
municipalities in assessing the use of treated municipal wastewater and sludge in producing crops for
human consumption. It highlights public concerns and regulatory issues likely to be faced, and also
identifies some additional areas for research.

The Committee on the Use of Treated Municipal Wastewater Effluents and Sludge in the
Production of Crops for Human Consumption consisted of 14 members with experience in soil and
crop science, agricultural engineering, wastewater and sludge treatment, soil microbiology, toxicology,
ecology, infectious disease, public health, economics, law, and other relevant fields. The committee
gained insights from a far larger group by inviting guests to its meetings, par-ticipating in field trips, and
reviewing the literature. My great appreciation goes to the committee, each of whom gave significant
time and energy to create this report. Additionally, I would like to thank Rufus Chaney and Richard
Bord for providing their time and resources to the study. I want to thank the staff of the WSTB,
especially Gary Krauss, study director, and Mary Beth Morris, project assistant. I would also like to
thank the study sponsors: the EPA, the U.S. Bureau of Reclamation, the USDA, the FDA, the
National Water Research Institute, the Water Environment Research Foundation, the National Food
Processors Association, the Association of Metropolitan Sewerage Agencies, California's Eastern
Municipal Water District, the Metropolitan Water Districts of Southern California, Bio Gro Division of Wheelabrator Water

Preface ix

Technologies, and N-Viro International Corporation. Without this support, the study would not have
Albert Page
University of California, Riverside

Chapter One    Introduction
Review of National Academy of Science's (NAS) 1996 literary review report by
its National Research Council (NRC) Committee :
 "Use of Reclaimed Water and Sludge in Food Crop Production"