COMPARATIVE RISK ASSESSMENT:

SETTING PRIORITIES FOR URBAN ENVIRONMENTAL MANAGEMENT IN

DEVELOPING COUNTRIES

Presentation by Barbara Britton

January 18, 2000

OUTLINE OF PRESENTATIONPart I Introduction and Background

Part II International Experience with CRA

Part III Methodology

PART I: INTRODUCTION AND BACKGROUND

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

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

ENVIRONMENTAL MANAGEMENT

Comparative Health Risk Assessment is used to set priorities for environmental management.

Risk Assessment

Risk Management

Identify and evaluate risks, set prioritiesamong problems.

Develop andimplement solutions forhigh priority problems

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

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 healthimpacts of several environmental conditions

Comparative Risk Assessment:evaluates and compares the potential health,ecological, and quality-of-life impacts ofseveral environmental conditions

PART II: INTERNATIONAL EXPERIENCE WITH

COMPARATIVE RISK ASSESSMENT

International Experience WithComparative 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

“HIGH RISK” PROBLEMS FROM FIVE CRAs

Environmental Problem Categories Bangkok Quito Cairo Ahmedabad Lima

Water, Sanitation, orMicrobial Diseases

Ambient PM

Indoor Air

Lead

Air Pollution from Transport

Solid Waste

CRA RESULTS: BANGKOK

Bangkok, Thailand (1990)

Airborne Particulate MatterLead ContaminationMicrobiological Diseases

Carbon Monoxide (CO)Other Metals

Toxic Air Pollutants

Surface Water ContaminationGround Water ContaminationPesticides & Metals in FoodSolid & Hazardous Wastes

High

Moderate

Low

Other Gaseous Air Pollutants (SO2, NO2, O3)

CRA RESULTS: CAIROCairo, Egypt (1994)

High

Moderate

Moderate/Low

Low

Airborne Particulate MatterLead (all media)Microbiological Diseases

Microbiological Contamination of FoodOzone

Other Gaseous Air Pollutants (SO2, CO)

Indoor Air PollutionDrinking Water (microbes, chemicals)Solid and Hazardous Wastes

Toxic Air PollutantsOther Water Pathways (e.g. fish, irrigation)

CRA RESULTS: AHMEDABAD

Ahmedabad, India (1995)

High

Moderate

Low

Air Pollution from Mobile SourcesAmbient Air Pollution (all sources)Indoor Air Pollution

Drinking WaterWastewater

Occupational HazardsTraffic HazardsFood Contamination

CRA RESULTS: LIMA

Lima, Peru (1997)

High

Moderate

Low

Inadequate Water SupplyInadequate SanitationSolid Waste

Surface and Groundwater ContaminationFood ContaminationAir PollutionWater Pollution (marine)

Hazardous WasteToxic SubstancesIndoor Air PollutionLoss of Landscaped Areas & Farm Land

PART III: COMPARATIVE RISK ASSESSMENT

METHODOLOGY

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

CONCEPTUAL MODEL LINKING ENVIRONMENTAL CONDITIONS AND

HEALTHSource

Discharge

Transport and Fate in the Environment

Transport and Fate in the Body

Dose Target Organs

Exposure

IntakeDamage, Disease, or Death

EXAMPLE:HEALTH RISK ASSESSMENT

Health Risk Assessment in Bangkok:

Population: 5.9 million

Airborne particulates: 90 - 200 g/m3

Health effects (per year): 9 - 51 million restricted activity days 300 - 1400 deaths

EXAMPLE:HEALTH RISK ASSESSMENT

Health Risk Assessment in Quito, Ecuador:

Population: 1.1 million

Pesticides in food:44.3 g/day intake of heptachlor11.0 g/day intake of aldrin

Health Effects:0.3 to 9.1 x 10-3 lifetime cancer riskUp to 150 excess cancer cases/year

EXAMPLE: COMPARATIVEHEALTH RISK ASSESSMENT

Quito, Ecuador (1993)

Risk Metropolitan Area

High Microbiological Diseases (Food)Airborne Particulate Matter

ModerateTraffic InjuriesDrinking Water and WastewaterIndoor Air QualityOccupational Disease and Injuries

LowSolid & Hazardous Waste DisposalPesticides in Food

Asentamientos Populares

Microbiological Diseases (Food)Airborne Particulate MatterIndoor Air QualityOccupational Disease and InjuriesDrinking Water and Wastewater

Traffic InjuriesSolid & Hazardous Waste Disposal

Pesticides in Food

CRA METHODOLOGY

¶ 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

Four Phases of Comparative Risk Assessment

FUNCTIONS AND RESPONSIBILITIESFunction Typical Unit

Project Management and oversight

Policy direction and project mandate

Public participation

Final risk ranking

Technical analysis--data collection, risk assessment, preliminary ranking

Project Manager

Steering Committee

Public Advisory Committee

Steering Committee or Public Advisory CommitteeTechnical Committees

The organization of a CRA must address five necessary functions:

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

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

ADAPTING TECHNICAL ANALYSIS FOR CRA IN DEVELOPING COUNTRIES

ISSUE RESPONSE

Scope includes infectious diseases, outside traditional risk assessment methods

Limited information and many data gaps.

Use health data from clinics and local survey to estimate disease rates.

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.

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

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. elderlypoor vs. middle incomevoluntarily exposed vs. involuntary exposedwomen vs. men

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