EHH500d – Spring 2002
Harvard School of Public Health
RISK ASSESSMENT
EHH500d – Spring 2002
Landmark Center Room 414A
2.5 credits
Instructors:
Jonathan I. Levy, Sc.D.
Assistant Professor of Environmental Health and Risk Assessment
Landmark Center Room 404K
(617) 384-8808; jilevy@hsph.harvard.edu
John S. Evans, Sc.D.
Senior Lecturer in Environmental Health
Center for Risk Analysis Room 211
(617) 432-1259; jevans@hsph.harvard.edu
Teaching Assistant:
Glenn Rice
Center for Risk Analysis Room L-215
(617) 432-4348; grice@hsph.harvard.edu
Framework of Course:
The field of risk assessment involves techniques for estimating the risks to humans or
ecosystems from chemicals, radiation, technology, or any other factors that can influence health and
well-being. Although risk assessment can cover a number of domains, in keeping with our
placement at a School of Public Health, we focus exclusively on human health in this course,
largely from chemical exposures. However, many of the techniques and concepts we will discuss
can be applied in other areas.
This course has been placed in the “D” period because it fundamentally involves the
integration of knowledge across numerous disciplines, many of which you have learned about
during the course of the year. Epidemiology and toxicology are used to understand the health risks
for a given level of exposure. Exposure can be estimated through field measurements or
mathematical models of pollutant fate and transport, and can sometimes include information about
human physiology to better understand the actual dose delivered to an organ. These and other pieces
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EHH500d – Spring 2002
of information are combined mathematically with a careful consideration of the relevant
uncertainties to arrive at estimates of risk useful for decision making.
In this course, we aim to explore all of the major components of risk assessment, learning
how to make the critical calculations but also exploring the underlying assumptions and considering
the implications for policy and public health. To the extent possible, we hope to make this class
discussion-oriented, drawing on the collective expertise of everyone in the classroom.
This course assumes some background knowledge, including basic calculus and statistics
and some familiarity with fate and transport modeling. There will be opportunities to review or
catch up on these concepts through TA sessions or one-on-one meetings with the instructors.
Course Grading:
Class Participation
Homework
Final Examination
20%
40%
40%
Required Book (available at the COOP):
Daniel M. Kammen and David M. Hassenzahl. Should We Risk It? Exploring Environmental,
Health, and Technological Problem Solving. Princeton University Press: Princeton, NJ, 2001.
(referred to as “SWRI” in the syllabus)
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EHH500d – Spring 2002
Tuesday, April 2: Introduction and Perspectives on Risk Assessment (Levy)
General topics:
- Group exercise: Defining risk assessment
- Overview of course and logistics
- Discussion of perspectives on risk assessment, implications for course
Thursday, April 4: Overview of Risk Assessment (Evans)
General topics:
- The four elements of a risk assessment
- Differences between cancer and non-cancer risk assessment
- Contrasting risk assessment and risk management
Readings:
- SWRI, Ch. 1 (p. 1-16)
- Ruckelshaus W. “Risk, Science and Democracy”. Issues in Science and Technology 1: 1938 (1983).
Homework for 4/9: SWRI Problem 2-A
Friday, April 5: Optional computer lab on Excel basics
Tuesday, April 9: Basic Models for Risk Assessment (Levy)
General topics:
- Strengths and limitations of stock-flow, simple dose-response models
- Applications and extensions
Readings:
- SWRI Ch. 2
- Masters GM. “Mass and Energy Transfer”, Ch. 1 in Introduction to Environmental
Engineering and Science. Englewood Cliffs, NJ: Prentice Hall, 1997 (p. 1-14).
Homework for 4/11: SWRI Problem 2-F, calculation exercise
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EHH500d – Spring 2002
Thursday, April 11: Statistics, Uncertainty, and Variability (Levy)
General topics:
- Differentiating between uncertainty and variability
- Overview of core statistical concepts
- Monte Carlo Analysis (theory and practice)
Readings:
- SWRI Ch. 3-4
Homework for 4/16: SWRI 4-D
Friday, April 12: Optional computer lab on Analytica
Tuesday, April 16: Exposure Assessment (Levy)
General topics:
- Concentration vs. exposure vs. dose
- Different approaches to estimating exposure
- Implications of variability
- Case study assignments
Readings:
- US EPA. Guidelines for Exposure Assessment. EPA/600Z-92/001. National Center for
Environmental Assessment: Washington, DC, 1992 (p. 16-49, 124-135).
Homework for 4/18: Reflecting on the Gaussian plume model (handout)
Thursday, April 18: Models for Exposure Assessment (Levy)
General topics:
- Extensions from the Gaussian plume model
- Different types of exposure models
Readings:
- McKone TE, Ryan PB. Human exposures to chemicals through food chains: An uncertainty
analysis. Environ Sci Technol 23: 1154-1163 (1989).
- Hoek G, Fischer P, van den Brandt P, Goldbohm S, Brunekreef B. Estimation of long-term
average exposure to outdoor air pollution for a cohort study on mortality. J Exp Anal
Environ Epidemiol 11: 459-469 (2001).
- US EPA. Mercury Study Report to Congress. Volume I: Executive Summary. EPA-452/R97-003. Office of Air Quality Planning and Standards (p. O-1-O-4, p. 2-2)
Homework for 4/23: Combining information across studies (handout)
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EHH500d – Spring 2002
Tuesday, April 23: Epidemiology and Risk Assessment (Levy)
General topics:
- Review of core epidemiological concepts
- Roadblocks for use in risk assessment - bias, confounding, extrapolation, causality
- Methods for combining evidence
Readings:
- Hertz-Picciotto I. Epidemiology and quantitative risk assessment: a bridge from science to
policy. Am J Public Health 85(4): 484-491 (1995).
- Wartenberg D, Simon R. Comment: Integrating epidemiologic data into risk assessment.
Am J Public Health 85(4): 491-493 (1995).
- Hill AB. The environment and disease: Association or causation? Proc Royal Soc Med 295300. (1965).
Homework for 4/25: SWRI 5-A
Thursday, April 25: Cancer Risk Assessment (Evans)
General topics:
- Sources of evidence used (epidemiology, toxicology, mutagenicity tests, structure-activity
analysis)
- Characteristics of rodent bioassay
- Animal-human extrapolations
Readings:
- Masters GM. “Risk Assessment”, Ch. 4 in Introduction to Environmental Engineering and
Science. Englewood Cliffs, NJ: Prentice Hall, 1997 (p. 117-162).
- Optional: Teuschler LK, Groten JP, Hertzberg RC, Mumtaz MM, Rice G. Environmental
chemical mixtures risk assessment: Current approaches and emerging ideas. Comments on
Toxicology 7: 453-493 (2001).
Homework for 4/30: SWRI 5-D
Tuesday, April 30: Models for Cancer Risk Assessment (Evans)
General topics:
- One-hit and multistage models
- Methods to estimate parameters of dose-response models
Readings:
- SWRI Ch. 5, p. 166-198
- Anderson EL et al. Quantitative approaches in use to assess cancer risk. Risk Analysis 3:
277-295 (1983).
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EHH500d – Spring 2002
Thursday, May 2: Models for Non-Cancer Risk Assessment (Evans)
General topics:
- Consideration of threshold assumption
- Definition of reference dose and reference concentration
- No observed adverse effects level vs. benchmark dose approach
Readings:
- Dourson ML, Stara JF. Regulatory history and experimental support of uncertainty (safety)
factors. Reg Tox Pharm 3: 224-238 (1983).
- Barnes DG, Daston GP, Evans JS, Jarabek AM, Kavlock RJ, Kimmel CA, Park C, Spitzer
HL. Benchmark dose workshop: Criteria for use of a benchmark dose to estimate a reference
dose. Reg Tox Pharm 21: 296-306 (1995).
Tuesday, May 7: Case Study: Health Effects of Power Plants (Levy, Evans)
Homework: Calculating the value of research (handout)
Thursday, May 9: Basics of Decision Theory (Evans)
General topics:
- Decision trees
- Value of information
Readings:
- SWRI Ch. 9
Tuesday, May 14: Risk Perception and Risk Management (Levy)
General topics:
- Influence of problem framing
- Implications for policy decisions
Readin77gs:
- SWRI, Ch. 10
- Wilson R, Crouch EAC. “Perception of Risks”, Ch. 4 in Risk-Benefit Analysis. Harvard
University Press, 2001 (p. 99-133).
- O’Brien M. “How Does Risk Assessment Actually Work?”, Ch. 2 in Making Better
Environmental Decisions. MIT Press: Cambridge, MA, 2000.
Thursday, May 16: Course Wrap-Up: A Case Study of Mercury (Levy, Evans, Rice)
Tuesday, May 21: Q&A
Thursday, May 23: FINAL EXAM
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EHH500d – Spring 2002
NAME ____________________________________________________________
(Write how you wish to be addressed.)
Degree Program ____________________________________________________
Dept. (and School if not HSPH) _______________________________________
Email _____________________________________________________________
Phone _____________________________________________________________
Background Coursework
Calculus (# of semesters):
Physics/Chemistry/Properties of Environmental Contaminants:
Computer Experience (Spreadsheet, Basic Programming, Stat Packages):
Biostatistics/Epidemiology:
Other relevant courses:
What do you hope to get out of this class?
________________________________________________________________________________
________________________________________________________________________________
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