Transcript Health impacts of use of biofuels in the rural areas of India

Health impacts of use of
biofuels in the rural areas of
India
Vijay Laxmi
&
Jyoti Parikh
• Scientific inquiry requires systematic characterization of the
exposure and health effects. Although an association between
indoor air pollution due to use of biofuels and ill-health effects
has been demonstrated in a number of studies, confounding
factors are not adequately controlled. Thus, in some studies we
have pollution measurements but not enough information about
socio-economic characteristics or in some cases disease
prevalence are recorded but no measurements of level of
pollution. This makes it difficult to understand a lot of
uncertainties in linking pollution with symptoms and physical
conditions of human beings.
• To understand these linkages between biofuels exposure, socioeconomic conditions and health impacts a comprehensive study
was carried out in 4 states of India covering 15,293 households
from 148 villages. To administer this study MRC Respiratory
symptoms questionnaire –1986 was used.
• A physical test was also used to capture respiratory health status
by recording lung function through peak flow expiratory (PEF)
meter. The physicians examined those found symptomatic on
the basis of MRC questionnaire for confirmation of disease.
• Individual health was recorded for about 80,000 (including both
direct and proxy responses) and 31,000 lung function were
recorded. State of the art equipment was used for monitoring
and measurement of the pollution in approximately 700
randomly selected households. Personal exposure of respirable
particulate matter (RPM) was recorded for the chief cooks. To
understand passive cooking effect area measurements were also
recorded for concentration of RPM in different
microenvironment of these households.
• The results of the pollution measurement show that in a
southern state i.e. Tamilnadu, the 24-hr mean exposure to
respirable particulates, of the chief cook is between 201± 48
µg/m3 for households using biofuels.
• This is far below the levels quoted in the literature of
1500µg/m3 for Northern India. However, North-South
difference in India (viz., Tamilnadu vs Uttar Pradesh) are very
pronounced due to differences in fuel types, type of food (rice
vs. chappati), types of kitchen and other culture (women's
status) and social characteristics (literacy). The mean exposure
in Tamilnadu is less than in some of the highly polluted urban
areas, but more than in the rural outdoors and small towns.
• The study reveals that smoking has much stronger impact than
biofuel smoke due to process of direct inhaling. Non-smoker
males also suffer from respiratory diseases. Biofuel use per se
was not as significant explanatory variable for respiratory
symptoms as the fuel index, which consists of type and number
of years of involvement (chief cook, helper or none). Fuel index
also captures the biofuels years along with type of involvement.
Even when biofuels are used, it is the housing characteristics
that determine the health impacts.
Health and Disease Data Record
HC
in terv iew s
HP
2
HH
Ind iv id ual P E F
in terv iew s h ealth
d ata
reco rd s
7 12
4 100
1 580
R aj.
4
1 989
1 195 5
2 705
UP
36
7 564
4 271 3
1 411 5
TN
9
5 028
2 2 251
1 200 0
T o tal
51
1 529 3
8 099 9
3 040 0
Health and Disease Data
Prevalence
N o . o f p erso n s p er
1000
H P R aj U P T N
R esp irato ry d isease sy m p to m s
40
70
60
32
C o u g h m o st d ay s fo r 3 m o n th s each
30
y ear
B rin g u p P h leg m fo r 3 m o n th s each y ear 6 0
50
50
31
90
80
31
S to p for B reath w h ile w alk in g at o w n
p ace
B lo o d in sp u tu m
20
40
30
30
10
40
20
7
A n y resp irato ry d isease sy m p to m s
160 240 240 131
Disease Inference from MRC
Questionnaire
Chronic bronchitis
Yes to cough for >3 months & >2 years as well as
sputum production >3 months & >2 years
Asthma
Yes to wheezing but no for chronic bronchitis plus Yes
to breathlessness
TB Blood in the sputum
Chest infection
Any chest infection with sputum formation in the last
year
Mean Concentration of RSP at Different
Kitchen Location using Fuel Wood (g/m3)
T y p e o f K itch en
P erso n al C o n c. in sid e
C o n c. o u tsid e
ex p o su re th e h o u se
th e h o u se
w h ile co o k in g w h ile
co o k in g
In d o o r
k itch en
1498
1411
215
w ith n o p artition s
S ep arate k itch en
1506
946
155
in sid e th e h o u se
S ep arate k itch en
1341
461
136
o u tsid e th e h ou se
O p en air co o k in g
894
203
209
C o n c. in sid e
th e h o u se
w h ile n o t
co o k in g
83
84
73
75
Significance of Reported Symptoms
and PEF with Socio-econmic Variables
Significance
Symptoms
PEF
Smoking : All states all symptoms
All states
Age
: All states all symptoms
All states
Fuel Index : All states all symptoms
All states
except for blood in sputum
Kitchen :
especially in UP
location
and females of Raj.
Significance of Reported Symptoms
and PEF with Socio-econmic Variables
Significance
Symptoms
Literacy : All states all symptoms
except “blood in sputum”
“eye irritation”
Land holdings :Not significant
No. of meals
: All states
No. of rooms : Except HP
PEF
Not significant
except Raj
All States
All states
Not significant
24- Hour Mean Exposure for
Respirable Particulates (g/m3)
C ooks
O th ers
clo se to th e
sto v e w h ile
co o k in g
far fro m sto v e w h ile
co o k in g
H o u ses u sin g
b io fu els
201±48
122±20
62±21
H o u ses u sin g
clean fu els
53±15
56±21
51±16
Personal Exposure to Respirable Dust
2500
Mean Concentration (ug/m3)
2048
2000
1702
1500
1498 1506
1354
1341
indoor kitchen with no partition
separate kitchen inside the house
separate kitchen outside the house
outdoor cooking
1201
1000
894
824
804
744
511
468
500
76
143
101 80
0
Firewood
Woodchips
Agricultural
waste
Type of Fuel
Kerosene
LPG