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, socio-economic 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

HCinterviews

HHinterviews

Individualhealthrecords

PEFdata

HP 2 712 4100 1580

Raj. 4 1989 11955 2705

UP 36 7564 42713 14115

TN 9 5028 22 251 12000

Total 51 15293 80999 30400

Health and Disease Data Prevalence

No. of persons per1000HP Raj UP TN

Respiratory disease symptoms 40 70 60 32

Cough most days for 3 months eachyear

30 50 50 31

Bring up Phlegm for 3 months each year 60 90 80 31

Stop for Breath while walking at ownpace

20 40 30 30

Blood in sputum 10 40 20 7

Any respiratory disease symptoms 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)

Type of Kitchen Personalexposure

Conc. insidethe housewhile cooking

Conc. outsidethe housewhilecooking

Conc. insidethe housewhile notcooking

Indoor kitchenwith no partitions

1498 1411 215 83

Separate kitcheninside the house

1506 946 155 84

Separate kitchenoutside the house

1341 461 136 73

Open air cooking 894 203 209 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

Symptoms PEF

Literacy : All states all symptoms Not significant except “blood in sputum” except Raj

“eye irritation”

Land holdings :Not significant All States

No. of meals : All states All states

No. of rooms: Except HP Not significant

Significance of Reported Symptoms and PEF with Socio-econmic Variables

Cooks Others

close to thestove whilecooking

far from stove whilecooking

Houses usingbiofuels

201±48 122±20 62±21

Houses usingclean fuels

53±15 56±21 51±16

24- Hour Mean Exposure for Respirable Particulates (g/m3)

Personal Exposure to Respirable Dust

1498

1201

2048

76 101

1702

14380

804894

824

468

13541506

511

1341

744

0

500

1000

1500

2000

2500

Firewood Woodchips Agriculturalwaste

Kerosene LPG

Type of Fuel

Mea

n C

once

ntra

tion

(ug

/m3)

indoor kitchen with no partition

separate kitchen inside the house

separate kitchen outside the house

outdoor cooking