1. Presentation by Barbara Britton
COMPARATIVE RISK ASSESSMENT: SETTING PRIORITIES FOR URBAN ENVIRONMENTAL MANAGEMENT IN DEVELOPING COUNTRIES
Presentation by Barbara Britton
January 18, 2000

2. OUTLINE OF PRESENTATION
Part I Introduction and Background
Part II International Experience with CRA
Part III Methodology

3. PART I: INTRODUCTION AND BACKGROUND

4. HISTORY OF COMPARATIVE RISK ASSESSMENT
First used in the U.S. in 1987
“Unfinished Business” evaluated 31 problems and changed USEPA priorities
Many projects completed for regions, states, and cities
Used outside the U.S. by USAID and USEPA
First assessment was in Bangkok, 1990
Assessments completed for about 10 cities and regions

5. What DID EPA Learn From Comparative Risk Efforts?
Chemical-Specific, Media-Specific, Technology-Based Approaches have Limitations
Policies Based on Comparative Risk Assessments Could Lead to More Efficient Use of Resources and Greater Protection of Public Health and the Environment

6. ENVIRONMENTAL MANAGEMENT
Comparative Health Risk Assessment is used to set priorities for environmental management.
Identify and evaluate
risks, set priorities
among problems.
Risk Assessment
Develop and
implement solutions for
high priority problems
Risk Management

7. ENVIRONMENTAL RISKS
Environmental damage may have three types of negative effects. 
Public Health--illness, injuries, deaths
Ecological--loss of species and habitat
Quality of Life--economic and social costs

8. TYPES OF “RISK ASSESSMENT”
Health Risk Assessment:
evaluates the potential public health impacts of an environmental condition
Comparative Health Risk Assessment:
evaluates and compares the potential health
impacts of several environmental conditions
Comparative Risk Assessment:
evaluates and compares the potential health,
ecological, and quality-of-life impacts of
several environmental conditions

9. PART II: INTERNATIONAL EXPERIENCE WITH COMPARATIVE RISK ASSESSMENT

10. International Experience With Comparative Risk Assessment
Bangkok: Accelerated plans for banning lead in gasoline
Cairo: USAID projects to reduce air pollution and lead contamination
Ahmedabad: Municipal program to reduce air pollution from transport
Lima: USAID environmental health project under design
Silesia: USAID technical assistance to high risk industrial facilities

11. “HIGH RISK” PROBLEMS FROM FIVE CRAs
Environmental Problem Categories
Bangkok
Quito
Cairo
Ahmedabad
Lima
Water, Sanitation, or
Microbial Diseases    
Ambient PM    
Indoor Air 
Lead  
Air Pollution from Transport 
Solid Waste 

12. CRA RESULTS: BANGKOK Bangkok, Thailand (1990)
Airborne Particulate Matter
Lead Contamination
Microbiological Diseases
Carbon Monoxide (CO)
Other Metals
Toxic Air Pollutants
Surface Water Contamination
Ground Water Contamination
Pesticides & Metals in Food
Solid & Hazardous Wastes
High
Moderate
Low
Other Gaseous Air Pollutants (SO2, NO2, O3)

13. CRA RESULTS: CAIRO Cairo, Egypt (1994) Airborne Particulate Matter
High
Moderate
Moderate/Low
Low
Airborne Particulate Matter
Lead (all media)
Microbiological Diseases
Microbiological Contamination of Food
Ozone
Other Gaseous Air Pollutants (SO2, CO)
Indoor Air Pollution
Drinking Water (microbes, chemicals)
Solid and Hazardous Wastes
Toxic Air Pollutants
Other Water Pathways (e.g. fish, irrigation)

14. CRA RESULTS: AHMEDABAD
Ahmedabad, India (1995)
High
Moderate
Low
Air Pollution from Mobile Sources
Ambient Air Pollution (all sources)
Indoor Air Pollution
Drinking Water
Wastewater
Occupational Hazards
Traffic Hazards
Food Contamination

15. CRA RESULTS: LIMA Lima, Peru (1997) Inadequate Water Supply
High
Moderate
Low
Inadequate Water Supply
Inadequate Sanitation
Solid Waste
Surface and Groundwater Contamination
Food Contamination
Air Pollution
Water Pollution (marine)
Hazardous Waste
Toxic Substances
Indoor Air Pollution
Loss of Landscaped Areas & Farm Land

16. PART III: COMPARATIVE RISK ASSESSMENT METHODOLOGY

17. STEPS IN RISK ASSESSMENT
Health risk assessment is quantitative, based on experimental and observational data.
Hazard Identification--
identify health risks associated with exposure
Dose-Response Assessment--
model the relationship between dose and effects
Exposure Assessment--
estimate a group’s exposure (amount, duration)
Risk Characterization--
estimate the probability and severity of effects

18. CONCEPTUAL MODEL LINKING ENVIRONMENTAL CONDITIONS AND HEALTH
Source
Transport and Fate in the Body
Discharge
Transport and Fate in the Environment
Dose Target Organs
Exposure
Intake
Damage, Disease, or Death

19. EXAMPLE: HEALTH RISK ASSESSMENT
Health Risk Assessment in Bangkok:
Population: million
Airborne particulates: g/m3
Health effects (per year):
million restricted activity days
deaths

20. EXAMPLE: HEALTH RISK ASSESSMENT
Health Risk Assessment in Quito, Ecuador:
Population: 1.1 million
Pesticides in food:
44.3 g/day intake of heptachlor
11.0 g/day intake of aldrin
Health Effects:
0.3 to 9.1 x 10-3 lifetime cancer risk
Up to 150 excess cancer cases/year

21. EXAMPLE: COMPARATIVE HEALTH RISK ASSESSMENT
Quito, Ecuador (1993)
Risk
Metropolitan Area
Asentamientos Populares
Microbiological Diseases (Food)
Microbiological Diseases (Food)
High
Airborne Particulate Matter
Airborne Particulate Matter
Indoor Air Quality
Occupational Disease and Injuries
Drinking Water and Wastewater
Traffic Injuries
Traffic Injuries
Moderate
Drinking Water and Wastewater
Solid & Hazardous Waste Disposal
Indoor Air Quality
Occupational Disease and Injuries
Solid & Hazardous Waste Disposal
Pesticides in Food
Low
Pesticides in Food

22. CRA METHODOLOGY Four Phases of Comparative Risk Assessment Planning
Determine scope of the study
Select and organize the team
Identify data types and sources
Data Collection and Analysis
Identify and gather data
Analyze data to estimate risks
Priority Setting
Interpret and compare risks
Debate and agree on priorities
Reporting
Prepare report as input to risk management planning

23. FUNCTIONS AND RESPONSIBILITIES
The organization of a CRA must address five necessary functions:
Function
Typical Unit
Project Management and oversight
Project Manager
Policy direction and project mandate
Steering Committee
Public participation
Public Advisory Committee
Final risk ranking
Steering Committee or Public Advisory Committee
Technical analysis--data collection, risk assessment, preliminary ranking
Technical Committees

24. PARTICIPATORY ASPECTS OF CRAs
Broad participation is critical because:
Analysis is multi-disciplinary and highly complex
Setting priorities are ultimately based on values
of the community
Broad participation is linked to acceptance of
CRA results and implementation of actions to
reduce risks

25. TECHNICAL ANALYSIS
Identify and evaluate health impacts of many environmental conditions
water and food
sanitation, drainage, and wastewater
ambient and indoor air, gases and particles
solid and hazardous wastes
occupational injuries and exposures
infectious, vector-borne, and pollutant-related diseases

26. ADAPTING TECHNICAL ANALYSIS FOR CRA IN DEVELOPING COUNTRIES
ISSUE
RESPONSE
Scope includes infectious diseases, outside traditional risk assessment methods
Use health data from clinics and local survey to estimate disease rates.
Limited information and many data gaps.
Use environmental, health, and qualitative data
Data are not computerized and are aggregated at inappropriate geographic levels.
Reorganize information; use assumptions and extrapolation where necessary.
Some standard exposure assumptions are inappropriate due to culture or conditions.
Adjust assumptions; conduct special studies if possible.

27. PRIORITY SETTING
Categorize each health impact by magnitude and severity
magnitude -- number of people affected
severity -- of effect, and importance of group affected
Combine magnitude and severity scores
Compare and categorize environmental problems
high, medium, and low risk

28. CRA Risk Ranking Risk ranking requires judgments based on values
Comparing health effects:
acute vs. chronic
disease vs accidents
Comparing effects among groups:
children vs. working adults vs. elderly
poor vs. middle income
voluntarily exposed vs. involuntary exposed
women vs. men

29. Conclusion
CRA’s can form an effective basis for urban environmental management planning
Allow cities to address worst environmental problems first
Broad-based participation is crucial to ensure risk ranking reflects views of entire community
Stakeholder involvement is pivotal to ensuring risk assessment results translate into management action