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EPA Response to the National Research Council (NRC) Report - A Review of the Technical Basis of the Chemical and Pathogen Regulations for Biosolids

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1993 to 1996 National Research Council Review

In early 1993, the U.S. Environmental Protection Agency's (EPA) suggested to the National Research Council's Water Science and Technology Board (WSTB) that it 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.

  • EPA was just finalizing the Part 503 Rule, Standards for the Use or Disposal of Sewage Sludge
  • A major implementation concern was with the food processing industry's reluctance to accept the practice

In 1993, WSTB formed a committee representing diverse expertise and perspectives to conduct an independent study of the safety and practicality of the use of sewage sludge for the production of crops for human consumption.

  • The committee produced a report in 1996 Use of Reclaimed Water and Sludge in Food Crop Production
  • Deemed useful for food processors, states, and municipalities in assessing the use of treated municipal wastewater and sewage sludge in producing crops for human consumption
  • The committee highlighted public concerns and regulatory issues likely to be faced, and also identifies some additional areas for research

2001 to 2002 National Research Council Review

Subsequently, in 2001 EPA asked the National Research Council (NRC) of the National Academy of Sciences to independently review the technical basis of the chemical and pathogen regulations for biosolids

  • The NRC’s Committee on Toxicants and Pathogens in Biosolids Applied to Land focused on human health to help address the questions and the requirement for periodic reassessment of the Part 503 rule
  • Searched for evidence on human health effects related to biosolids exposure and the technical methods and approaches used by EPA to establish its human-health-based chemical and pathogen standards for biosolids

In 2002 the NRC released its report Biosolids Applied to Land, Advancing Standards and Practices

  • The overarching conclusion by the NRC Committee was that there is no documented scientific evidence that the Part 503 rule has failed to protect public health

  • However, the NRC noted that further research is needed and made recommendations for addressing public health concerns, scientific uncertainties, and data gaps in the science underlying the sewage sludge standards.

EPA's Response to National Research Council's 2002 Review

In response to the NRC 2002 report, the Agency released in 2003 a final Agency response to the National Research Council report in the form of a 14-Project Action Plan, as well as the results of EPA's review of existing sewage sludge regulations.

Provided below are two NRC documents and other information highlighting EPA's response to the 2002 NRC report and progress towards completing action plan activities.

If you have trouble accessing any content in the following documents, please contact Liz Resek ( or by phone (703-347-0391).

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