Approaches to Studying the Relationships Among Poverty, Air Pollution, and Health in Ho Chi Minh City, Vietnam Sumi Mehta and Aaron Cohen Public Health and Air Pollution in Asia (The PAPA Program)

Overview Background: air pollution, poverty, and health Objective: designing portable study approaches for HCMC context Insight from a recent technical visit to HCMC Possible Approaches

Why the poor may suffer more health effects from air pollution The poor suffer higher exposures to air pollution Living close to traffic Roadside occupational exposures Small and medium scale enterprises / Cottage industries Use of solid fuels for cooking The poor are more susceptible to air pollution Poor nutrition / immunosuppression Higher incidence of ‘diseases of poverty’ Lack of timely access to health care Limited evidence from the West, but a clear need to explore this issue in the Asian context

Higher Risks Among the Less Educated Evidence from HEI Reanalysis Attained education inversely associated with PM relative risk in ACS and Six-Cities studies An indicator of social class Due to differences in true exposure? Sensitivity to air pollution?

Studying Air Pollution, Poverty, and Health in HCMC Initiated at the request of ADB Identify feasible approaches to studying poverty, air pollution, and health in HCMC Methods appropriate for HCMC Methods suitable for use in other cities  building an evidence base across Asian cities

Studying Air Pollution, Poverty, and Health in HCMC: A Technical Visit to HCMC An interdisciplinary team of researchers and local authorities in air quality, exposure assessment, health (epidemiology), social science Goals: identify possible geographic areas/populations for investigation who are the poor? where do they live? Evaluate availability, quality, and collection frequency of routinely collected data on air quality, health outcomes Assess feasibility of collecting supplemental data

Kirk Smith, Sumi Mehta, Aaron Cohen, Le Van Khoa, Vo Tan Dam, Bjarne Sivertsen, Mr. The, Phan Quynh Nhu, Ms. Van Collaborators ADB PAPA NILU East-West Center UC Berkeley HEPA US AEP

Housing and Poverty in HCMC A housing survey has identified over 100 ‘slum’ areas in HCMC, defined as having 50 or more houses with ‘shanty’ housing structures (DONRE and others) ‘Shanty’ housing is highly correlated with income in HCMC Concentrated areas of poverty does exist within HCMC While the poor used to live mainly along the canals, these are the first areas targeted in resettlement programs While many canal-side shanty areas have been cleared, many others still exist

Shanty Areas in HCMC

Canal-Side Slum

Slum and Replacement Housing

Health Data in HCMC Quality and availability of data varies tremendously by level of care and speciality Local clinics report case summaries, but seldom keep detailed patient records Hospitals use similar intake forms, but record keeping systems vary Electronic data available at Pediatric Hospital #1, Respiratory Hospital for many years Includes financial records (payment exemptions for the poor)

Air Quality Data: Currently Available: 9 Functioning automatic monitoring stations with high quality air quality information collected daily (HEPA)

Roadside Monitoring Station Maintained by HEPA, with assistance from NILU

Approaches to Exposure Assessment Modeling approach based on existing air quality data In progress: spatially resolved air quality estimates at the ward (zip code) level Integrate data from air pollution monitors, traffic density, emission inventories (AirQUIS) Work conducted by HEPA, with guidance from NILU Key issues relevant to health studies: Does the model indicate a distribution of exposures across the city? How well does the model represent individual / household exposures?

Approaches to Exposure Assessment Neighborhood / personal exposure assessment Validates the modeled estimates of exposure Addresses other local ‘hot-spots’/ microenvironments for exposures not included in the exposure model Time spent in traffic Cooking with solid fuels (wood, coal) and/or poorly combusted kerosene Environmental tobacco smoke (ETS) Occupational exposures (street vendors, traffic police, drivers)

Solid Fuel Use in Canal-side Household

Possible Applications of Exposure Estimates in Health Studies Hospital based studies Case-control, case crossover studies Use modeled ward level estimates to represent individual exposures Use individual / neighborhood exposures to refine exposure estimates, aid in process of selecting controls Community based studies Prevalence studies conducted during neighborhood exposure assessment

Discussion Health effects of air pollution in Asia are likely to be more severe among the poor, but the evidence base is lacking. Informative studies require an integration of data and expertise from aerometrics, exposure assessment, epidemiology, and social science. Initial assessment is that such studies can be conducted in HCMC. Approaches are being developed with the specific intent to be used in other cities.

Kirk Smith, Sumi Mehta, Aaron Cohen, Le Van Khoa, Vo Tan Dam, Bjarne Sivertsen, Mr. The, Phan Quynh Nhu, Ms. Van Collaborators ADB PAPA NILU East-West Center UC Berkeley HEPA US AEP