Does higher spatial resolution of identification strategy can detect weaker causal effect of forest
fire on human health in Indonesia?
○ Gonang May PERDANANUGRAHA * , Shinji KANEKO *１ ． Introduction
Indonesia experienced the worst forest fires catastrophe in 1997 which lead to childmortality, respiratory problems, to children stunting. Those impacts were proven by
many literatures, some of those literatures used satellite spatial information thatwas called TOMS (Total Ozone Mapping Spectrometer) in measuring aerosol index or hazelevel above the ground which already grounded in 2005, to identify which areas wereexposed and not. After 1997, there was another forest fires episode in 2006. Literally,
it was much less severe than the previous , which is impossible to measure via TOMS
aerosol index. Other measurement of aerosol is offered by MODIS (Moderate Resolution
Imaging Spectroradiometer) through aerosol optical depth (AOD) which is still
operated until today. Fortunately, this new measurement has better spatial resolution
than the predecessor, which means we can more precise in identifying the locations
exposure severity. By utilizing this measurement, our research question: is thatpossible finding the effect(s) on people’s health from lower exposure in 2006 forest
fires, by conducting causal inference approach to large scale panel dataset.

２ ． Methodology
In this research firstly we conduct identification strategy by utilizing MODIS AOD
to identify which areas/regions were impacted and not. Secondly, we use IFLS
(Indonesian Family Life Survey) which contain individual health status and location
information of every household and individual until village level. Thirdly, we match
between locations exposed status with household and individual locations, in orderto determine treated and control group. Lastly, we implement econometric approach
to find the causal effects, because we use panel data and forest fires are considered
as natural experiment. Therefore, we use difference -in-differences (DiD) to as sessindividual health status from those two groups before and after treatment. Healthstatus that we analyze is related with new born babies, either this weaker exposure
has effect to babies death, miscarriage/stillbirth, or babies weight .
*Graduate School fo r Inte rnational De velopment & Cooper ation, Hiroshima Uni versity〒739-8529 Hiroshi ma-ken, Hig ashi-Hiroshim a, 1-5-1 Kagami yam a, TEL 082-424-6905 & FAX082-424-6904 E-m ail: d176088@hi roshima- u.ac.jp

３ ． Results
By comparing the treated a nd control group

Ta ble 1 . DiD regression of main analy sis
(i )

(i i)

0.013

0.003

(0.022)(0.022)

Sample Size

1873

1751

Mi scar riag e/St illbi rth

0.056

0.027

(0.038)(0.031)

before and after treatment with DiD, wefound that 2006 forest fires have negative

Ba bies Dea thsignificant effect to new born babies weightaround-0.2kg.

Which

means

individual

mothers during prenatal periods who lived in
exposed regions are tended to have lessweight new born babies 0.2 kg, compared toSample Size

2070

1876

mothers who lived in non-exposed locations

Bi rth Weig ht-0.221**-0.17*(0.093)(0.095)during their prenatal periods. On the other
hand, we did not find any significant result

Sample Size

1636

1557

in the other two outcomes (babies death andBabies & Mother sNoYes

miscarriage/stillbirth).

TheseCharacteristic

arerobustness

supportedbysomefindings
and•estimated by li near regres sionconsistency checks that we did in order tomake sure that the findings are purely

Means and Stand ard Errors are•Inference: *** p<0.01; ** p<0.05; *p<0.1

because of 2006 exposure. Robustness andconsistency check that we did are placebo•

S. Err. in pare ntheses

test, compare to alternative control, and•

0 = Baby Death; 1 = Baby A live

sensitivity analysis.

•0 = Miscarriage /Stillbirth ; 1 =Livebirth４ ． Conclusion•Birth Weight in kg

Even though, 2006 forest fires event was not as great as 1997 calamity, but it wasstill as an environmental tragedy that the haze exposure could lead to serious healthissues. Through this research, it is proven that the event had significant negative
effect to the new born babies weight. Furthermore, the exposed pregnant mothers willtend to have less weight of new born babies around 0.2 kg, compared to the non -exposed
pregnant mothers. This finding is strengthen by several robustness and consistency
checks. The main reason that we can find the effect from the weaker exposure, becausefrom the beginning we utilize better identification strategy than the previous
literatures which discuss the 1997 event. By using this higher spatial resolution,
we can identify more precisely if the locations were really exposed or not.