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Running Head: Fox River Risk Assessment Teaching Tool

Received 5 September 2003; accepted 5 September 2003

ABSTRACT

In 1999 and 2000, two environmental consulting companies independently prepared risk assessments of the Lower Fox River waste site in Wisconsin. Because the two assessments produced somewhat different risk characterizations, the Association for Environmental Health & Sciences was asked by the site’s Potentially Responsible Parties to form a peer review panel to critique and compare the two assessments. The panel found interesting differences between the two risk assessments and recommended that their observations, together with the two risk assessments, be made available as a Teaching Tool for persons interesting in conducting human and ecological risk assessments. An accompanying CD contains these and other materials useful for teaching purposes.

Key Words: risk assessment, Fox River, ecological risk assessment, human risk assessment.

INTRODUCTION

Welcome to our special risk assessment teaching tool. This issue of HERA contains a CD on which you will find human health and ecological risk assessments for the Lower Fox River waste site in Wisconsin. These assessments were prepared by risk assessment professionals from two well-regarded environmental consulting companies.

One set of assessments (human health and ecological) was prepared for the Wisconsin Department of Natural Resources (WDNR) (ThermoRetec Risk Assessment); the other was prepared for the Fox River Group, the Potentially Responsible Party (PRP) at the site. In 1999, the Fox River Group contracted with the Association for Environmental Health & Sciences (AEHS) to conduct an analysis of the two risk assessments. The disparate results of the assessments initiated the need for such a review. A peer review panel was formed to study the site and the two assessments.

During the review process, the panel, all of whom had taught toxicology or risk assessment at leading universities, noted the usefulness of publishing this type of review for the purpose of instructing students in the risk assessment process. As a result of that observation, HERA’s editors decided to publish the information in a format that would enhance its value as a teaching tool. Thus, the two original risk assessments, along with the peer review panel’s comments and the WDNR Record of Decision for the Fox River waste site, are provided on the CD enclosed with this issue of HERA. These comments are presented in a format that should make them easily accessible to compare with the original risk assessments on the CD.

The ThermoRetec Risk Assessment (1999) that appears on the CD is the first iteration (a Screening Level, 1999) of a document that was subsequently revised, incorporating not only comments from the AEHS’s peer review panel, but also public and industry concerns. These revisions were considered before the WDNR (2002) made final decisions regarding the site.

The AEHS peer review panel consisted of nationally known environmental scientists:

Mohamed Abdel-Rahman, New Jersey Medical School: Panel Chair, Human Health Risk Assessment
Halina Brown, Clark University: Panel Member, Human Health Assessment
Raymond Yang, Colorado State University: Panel Member, Human Health Assessment
Chris Metcalfe, Trent University: Panel Chair, Ecological Risk Assessment
Christopher Teaf, Florida State University: Panel Member, Ecological Risk Assessment
Richard DiGiulio, Duke University: Panel Member, Ecological Risk Assessment
Barbara Callahan, University of Massachusetts. Project Officer
Paul Kostecki, University of Massachusetts: Project Co-Director
Edward Calabrese, University of Massachusetts, Project Co-Director

SUGGESTIONS ON USE OF THE CD AS A TEACHING TOOL

Each instructor will have his/her own ideas on how the Teaching Tool can be used effectively. These risk assessments benefit from the evaluation of one of the more contentious and interesting groups of toxicants, PCBs. For human health risk assessments, descriptions of populations at, or next to, the site can be used for students to identify their own receptors. Discussions regarding whether intake parameters are correct will be debated by those with differing opinions. Input parameters can be evaluated with respect to the U.S. Environmental Protection Agency’s default values (USEPA 1997) or site-specific values such as the fish ingestion rates of the Hmong/Laotian subpopulations described in the assessments. Both Central Tendency Estimates (CTE) and Reasonable Maximum Estimates (RME) are explained and calculated. How absorption factors are utilized in risk assessment is a significant part of the assessments as well.

For ecological risk assessment, conceptual models can be evaluated and inputs to models calculated. Data included are items such as habitat alteration and the effect of the site toxicants on various species, e.g., fish, terns, cormorants, bald eagles, mink, etc. Uncertainties associated with exposure models are also addressed. Thus, the level of study could be employed for beginning risk assessors to the most experienced in this field. We expect that instructors will manipulate the information for their own specific needs. It could also be used in concert with the 2003 August issue of HERA, an issue devoted to celebrate the 20th anniversary of the so-called Red Book, the first federal risk assessment guidance from the National Research Council (NRC 1983).

We hope that this Teaching Tool will provide insights into risk assessment methodology along with its strengths and limitations.

To view the Teaching Tool, click here.

Wisconsin ROD

Fox River Exponent

REFERENCES

AEHS (Association for Environmental Health & Sciences). Peer Review Panel Report for the Fox River Risk Human and Ecological Risk Assessments. Amherst, MA, USA

Exponent. 2000. Baseline Human Health Risk Assessment of PCBs in the Lower Fox River System. Landover, MD, USA

NRC (National Research Council). 1983. Risk Assessment in the Federal Government: Managing the Process. National Academy Press, Washington, DC, USA. January 2000

ThermoRetec. 1999. Baseline Human Heath and Ecological Risk Assessment: Lower Fox River, Wisconsin. Seattle, WA, USA. February 24

USEPA (US Environmental Protection Agency). 1997. Exposure Factors Handbook. Washington, DC, USA

WDNR (Wisconsin Department of Natural Resources). 2002. Record of Decision Operable Unit 1 and Operable Unit 2 Lower Fox River and Green Bay, Wisconsin: Responsiveness Summary. Madison, WI, USA

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