A Case-Control Study on Traffic-related Air Pollution

and Asthma Prevalence and Suggestions on Possible

Interventions in Select Communities in Metro Manila

An HSc 55 Thesis Topic Proposal by Abacan, Balmaceda, Capinpuyan, Chong, Neric, Venturina

research questions

research questions

How strong is the association between exposure to traffic-

related air pollution and asthma cases?

What kind of preventive measures can be

implemented to reduce incidence according to this

information?

significance & rationale

significance & rationale

Asthma is a chronic disease that may be detrimental to individuals.

Association of air pollutants and asthma is

well studied.

In the UK, high truck traffic exposure = high symptoms of asthma. (Brunekreef B, et.al. 2009)

significance & rationale

Metro Manila Study shows positive association between concentration of particulate matter (PM2.5 and PM10) and morbidity rate of asthma. (Estanislao, et al., 2011)

PM is produced by vehicle emissions, most predominantly in the transport

sector. (Vergel, 2007)

significance & rationale

"69.8% of the total person trips are public transport trips (jeepney, bus, tricycle and rail."

significance & rationale

DOH declared on Feb. 12, 2012 Manila air is hazardous.

DOH requires further studies on

asthma

Studies on asthma and traffic-related air pollution will help create accessible preventive and intervention measures.

objectives(general & specific)

general objective

To determine the association between exposure to traffic-related pollutants and the development of

asthma and occurrence of asthma attacks

among communities in Metro Manila and to use these as indicators in

formulating intervention and prevention measures.

specific objectives

To use the case-control method in studying the variables.

To be able to correctly distinguish between asthma cases and controls that would represent our target population best.

1

2

specific objectives

To choose cases and controls from a particular city with highest Particulate Matter concentration and high asthma incidence based on a previous study* (Pasig, Pateros, Taguig, San Juan or Makati).

* Respiratory Disease and Varying PM2.5 and PM10 concetrations in Metro Manila from 2001-2007 by Estanislao, et al. (2011)

3

specific objectives

To identify individual exposure to traffic-related air pollution according to traffic density of residential and work area in terms of cars per day per meter (car/day/m)* by obtaining data from DPWH and MMDA traffic records.

*"Traffic related air pollution and incidence of childhood asthma: results of the Vesta case-control study"Zmirou, et al.

4

specific objectives

To obtain emission levels using DENR data and find an association with types of vehicles accessing the roads.5

variables

variables

levels of exposure to traffic-related air pollution: traffic density vs.

emission levels

INDEPENDENT VARIABLE:

LOW TRAFFIC DENSITY

+HIGH

EMISSION

LOW TRAFFIC DENSITY

+LOW

EMISSION

HIGH TRAFFIC DENSITY

+LOW

EMISSION

HIGH TRAFFIC DENSITY

+HIGH

EMISSION

variables

Prevalence of asthma cases

DEPENDENT VARIABLE:

variables

1 Family (genetic) history of asthma

2 Exposure to other types of air pollution (i.e. second-hand smoke)

CONFOUNDING VARIABLES:

variables

1 All subjects should have resided and worked in Metro Manila for a significant number of years.

2 All subjects should be part of comparable socio-economic groups.

CONTROL VARIABLES:

hypothesis

hypothesis

There is a significant association between levels of exposure to traffic-related air pollution and prevalence of asthma in Metro

Manila.

references

references

1. Zmirou, D., et al. "Traffic related air pollution and incidence of childhood asthma: results of the Vesta case-control study" (2004) Journal of Epidemiology and Community Health 58: 18-23

2. Respiratory Disease and Varying PM2.5 and PM10 concetrations in Metro Manila from 2001-2007 by Estanislao, et al. (2011)

3. Vergel, Karl B. N. National Center for Transporation Studies. "Estimation of Local and Greenhouse Gas Emissions and Energy Demand of Road Transport in Metro Manila". National Center for Transporation Studies. 2007. PDF file.

Thank you for listening!

Abacan, Balmaceda, Capinpuyan, Chong, Neric, Venturina