Welcome to the Web Site for ENST 78 (also ENVR 78)
Risk-Based International Environmental Decisions

ENST 78 is a web-based course that may be taken during any semester (including the summer semesters), but is most effective if taken during the summer semesters when it is linked through the web to the Summer Program in International Environmental Risk Assessment taught at the University of Salzburg. Still, all required components of the course may be completed during any given semester.

In addition, depending on how a student takes the course, there may be a teaching assistant. This will be particularly true for students taking the course at one of the Field Sites maintained around the world by the Carolina Environmental Program.

Course Description

This course provides an overview of the philosophical, theoretical and (some) mathematical/quantitative foundations of risk analysis as applied to environmental problems, with a focus on human health risk assessment. Equal attention is directed towards:

• philosophical features of discourse within risk analysis;
• the nature of risk and risk characterization;
• evidence available to risk analysts and use of that evidence in warranting conclusions;
• the treatment of uncertainty, variability and sensitivity;
• models for estimating human health risks;
• the performance of human health risk analyses for regulatory and other purposes; and
• the role of risk analysis within regulatory and other environmental decisions.

The course explores both the mechanics of performing a risk analysis and criteria by which analyses are justified and critiqued in the scientific and policy arenas. Emphasis is placed on the role of rationality in risk analysis, reasons for disagreement between risk analysts, and the relationship of risk analysis to science, philosophy and policy decisions. These decisions are not restricted to public decisions, but include decisions by individuals, corporations and other agencies.

There are no lectures involved in the course (this being an internet-based course). Instead, students are assigned a series of exercises built around the methods of analysis underlying the course and around the readings. Each exercise results in a mini-project with a report to be transmitted to the instructor by the end of the semester. The projects must be conducted by individual students, although students are free to discuss the projects and share resources. The exercises may be conducted in any sequence, and reports may be submitted at any time during the semester, but they are most effective if conducted in the sequence suggested below. In this way, the analytic methods learned will follow the format of a risk assessment and the mini-projects will build towards the final examination. When completed, the reports and final examination should be submitted electronically to the instructor.

Email your report or exam to Douglas Crawford-Brown

You may also send any inquiries concerning the course, the mini-projects, the reports, the examination, and/or the readings to the above email address. They will be answered as soon as possible.

Grades are based on the 5 mini-projects (counting 10% each, for a total of 50% of the final grade) and a final exam (counting 50). Students may download the final examination at any time during the semester to ensure that material covered in the exam is being considered as the separate assignments are being completed.

The primary text is Risk-Based Environmental Decisions: Methods and Culture by Crawford-Brown (Kluwer Academic Publishers, 1999), which should be purchased from the instructor. In addition, the following selections from other books are required readings:

• N. Choucri, "Introduction: Theoretical, Empirical and Policy Perspectives", Chapter 1 in Global Accord: Environmental Challenges and International Responses, edited by N. Choucri, MIT Press, Cambridge, Mass., 1993.

• D. Victor, A. Chayes and E. Skolnikoff, "Pragmatic Approaches to Regime Building for Complex International Problems", Chapter 14 in Global Accord: Environmental Challenges and International Responses, edited by N. Choucri, MIT Press, Cambridge, Mass., 1993.

• J. Graham and J. Wiener, Chapter 1, "Confronting Risk Tradeoffs", in Risk vs. Risk: Tradeoffs in Protecting Health and the Environment, edited by J. Graham and J. Wiener, Harvard University Press, Cambridge, Mass., 1995.

• J. Graham and J. Wiener, Chapter 7, "Seeking Safe Drinking Water", in Risk vs. Risk: Tradeoffs in Protecting Health and the Environment, edited by J. Graham and J. Wiener, Harvard University Press, Cambridge, Mass., 1995.

• J. Graham and J. Wiener, Chapter 11, "Resolving Risk Tradeoffs", in Risk vs. Risk: Tradeoffs in Protecting Health and the Environment, edited by J. Graham and J. Wiener, Harvard University Press, Cambridge, Mass., 1995.

• L. Caldwell, Regional Arrangements: Bilateral and Multilateral Agreements", in International Environmental Policy: Emergence and Dimensions, Duke University Press, Durham, NC, 1990.

Copies of all of these books are in the Reading Room of the Environmental Sciences and Studies Program on the second floor of Miller Hall on the UNC-CH campus.

Course Topics

The list below is of the topics covered in the class. As mentioned above, they are best explored when covered in the order shown, although not necessarily with equal amounts of time devoted to all topics. Still, students may re-arrange topics in any order desired, so long as all 5 mini-projects are submitted before the last day of the semester (as specified by the instructor) and so long as all topics are completed before the final examination is transmitted to the instructor for grading. You will select a source of risk early in the assignments, so you must complete the Topic 1 Assignment before the others. Choose this source well, since you will have to live with it throughout the course!

Topic 1. The Philosophical Foundations of Risk Analysis. The nature of rationality and analytic thought. The meaning of environment, risk, and risk analysis. The development and use of influence diagrams and logic trees in risk analysis. Readings: Chapter 1, Crawford-Brown.

Go to the First Topic Assignment and Exercise Page

Topic 2. The Structure of Risk Assessment and of Hazard Identification. How a risk assessment is structured. Categories of evidence in hazard identification. The nature of rationality, evidence and evidential reasoning. Categories of human health effects. Weight-of-evidence determinations. Reading: Chapter 2, Crawford-Brown.

Go to the Second Topic Assignment and Exercise Page

Topic 3.Risk and Decisions in the National and International Setting. How risk is viewed in the context of decisions, particularly when risks must be balanced and values are in conflict. Differences in the nature and use of risk assessment by individuals, organizations, regulatory bodies and the court. The role of human values in risk assessment. The relationship of risk to societal activities. Environmental organizations and their use of risk assessment. Readings: Choucri; Chapter 1, Graham and Wiener; Caldwell.

Go to the Third Topic Assignment and Exercise Page

Topic 4. Principles of Exposure Assessment. Issues of characterizing exposure in relation to environmental systems and human populations. The four-dimensional nature of exposure. Summarizing exposure through statistical analysis. Cultural factors controlling exposure. Reading: Chapter 3, Crawford-Brown.

Go to the Fourth Topic Assignment and Exercise Page

Obtain the Multipathway Exposure Model

Topic 5. Exposure-Response Relationships. The relationship between environmental stresses and the risk to human populations. Models used to estimate risk following exposure. Principles of regulatory science; the precautionary principle; ample margin of safety. Readings: Chapters 4 and 5, Crawford-Brown; Graham and Wiener, Chapter 7.

Go to the Fifth Topic Assignment and Exercise Page

Topic 6. Uncertainty, Variability and Sensitivity Analysis. Monte Carlo approaches to uncertainty and variability analysis within logic trees. Confronting uncertainty in decisions. The strategic use of uncertainty in negotiations and the court. Building epistemic communities and regimes to moderate uncertainty. Readings: Chapter 6, Crawford-Brown; Victor, Chayes and Skolnikoff.

Go to the Sixth Topic Assignment Page

Final Examination (to be taken individually by each student, and not in any groups). The examination consists of application of the methods of analysis to a problem of environmental risk.

Go to the ENST 78 Final Exam