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

Health and Disease Data Prevalence

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/m 3 )

Significance of Reported Symptoms and PEF with Socio-econmic Variables Significance SymptomsPEF 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 SymptomsPEF Literacy: All states all symptoms Not significant except “blood in sputum” except Raj “eye irritation” Land holdings:Not significantAll States No. of meals: All statesAll states No. of rooms: Except HPNot significant Significance of Reported Symptoms and PEF with Socio-econmic Variables

24- Hour Mean Exposure for Respirable Particulates (  g/m 3 )