Skip to main content


Buy Article:

$9.50 plus tax (Refund Policy)

Or sign up for a free trial

There is currently a substantial amount of interest and controversy regarding the beneficial reuse of biosolids in the United States and worldwide. U.S. Federal laws regulating allowable levels of chemical contaminants in biosolids (Part 503 Rule) were developed using a risk-based methodology. However, the maximum allowable levels of microbiological contaminants in biosolids were based on performance or technology-based standards, management, and record keeping practices, because microbiological risk assessment methodologies were not sufficiently developed at the time that the Part 503 rule was promulgated. The first step in addressing potential concerns related to microbial pathogens in biosolids is to critically evaluate the potential risk to public health that may be associated with exposure to biosolids.

A three year Water Environment Research Foundation (WERF) investigation was recently completed in which a methodology was developed for characterizing the risks to human health from pathogens via exposure to biosolids (Colford et al. 2003; Eisenberg et al. 2004). For both infectious and noninfectious disease processes, infectivity as a function of dose (estimated using a dose-response function) is an important factor to account for when estimating risk. There are, however, other factors that also potentially play an important role in infectious disease processes. Such factors include but are not limited to person-to-person transmission, immunity, asymptomatic infection, and incubation period. The methodology developed during this WERF investigation employs a population-based model that explicitly accounts for those properties that are unique to an infectious disease process.

To demonstrate the applicability of this risk-based method, numerical simulations were carried out for a case study example in which the route of pathogen exposure was direct consumption of biosolids-amended soil and the pathogen present in the soil was enterovirus. The output from the case study yielded a decision tree that differentiates between conditions in which the relative risk from biosolids exposure is high and those conditions in which the relative risk from biosolids is low. This decision tree illustrates the interaction among the important factors in quantifying risk for the exposure scenario investigated. For the case study example, those factors include biosolids treatment processes, the pathogen shedding rate of infectious individuals, secondary transmission and immunity.

An overview of the risk assessment methodology will be provided. Case study results will be summarized, and the status of related ongoing research will be presented.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Data/Media
No Metrics

Document Type: Research Article

Publication date: 2004-01-01

More about this publication?
  • Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed.

    A subscription to the Proceedings of the Water Environment Federation includes access to most papers presented at the annual WEF Technical Exhibition and Conference (WEFTEC) and other conferences held since 2000. Subscription access begins 12 months after the event and is valid for 12 months from month of purchase. A subscription to the Proceedings of the Water Environment Federation is included in Water Environment Federation (WEF) membership.

    WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access. Access begins 12 months after the conference or event
  • Subscribe to this Title
  • Membership Information
  • About WEF Proceedings
  • WEFTEC Conference Information
  • Learn about the many other WEF member benefits and join today
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more