Assessment of Improved Cook Stove in Reducing Indoor Air Pollution and Health Impact in Nepal (Study period: 2008-2009)
Ashish Singh and Bhushan Tuladhar, Research and Development Unit, Environment and Public Health Organization, Kathmandu, Nepal. www.enpho.org , ashish.envs@gmail.com, Bhushan.tuladhar@gmail.com
1. Introduction
With more than 80 percent of the population depending on solid biomass fuel, such as wood, dung and agricultural residues for cooking, indoor air pollution (IAP) is a major problem in Nepal. World Health Organization (WHO) estimates that 2.7 percent of Nepal’s national burden of disease is attributed to IAP related diseases. Likewise, the total death was estimated 7500 deaths per year (WHO, 2007).
For alleviating the smoky kitchen, improved cook stove (ICS) is a popular biomass energy technology in Nepal. The Alternative Energy Promotion Centre/Energy Sector Assistance program (AEPC/ESAP) has been promoting the mud ICS in Nepal. So far more than 275,000 stoves have been installed in the country.
2. Research Objectives
To monitor the effectiveness of ICS promoted by AEPC/ESAP in reducing IAP and improving health in Nepal.
3. Research Methodology
The study followed the “Before-After” design referring to simple monitoring methodology by developed by Edwards et al., 2007, and Smith et al., 2007. It is a longitudinal research design that in principal requires monitoring in the same household before (i.e. while using Traditional cook stove, TCS) and after the installation of ICS. The monitoring of ICS was conducted twice once after 3 months and after 1 year of use. A total of 47 sample households were estimated as the sample size for the study, assuming a detectable difference of 50% and co-efficient of variance (COV) of 1 (Edwards et al., 2007) and 50% of extra sample for possible dropouts.
3.1 Selection of study site
Selection of study site was based on two factors: geographical distribution of ICS program and socio-cultural variation found in different regions of Nepal. Therefore, for proper representation, the study had selected– Dang in the western region representing Inner Terai (<500 meters), Dolakha (1500-2000 meters) in the central region representing high hills and Ilam in the eastern region representing mid hills (800-1500 meters).
3.2. Studies Parameters
a) Indoor air Pollutants: 24 hr mean concentration of Particulate matter (PM2.5) and Carbon monoxide(CO) b) Health Survey of Mother and Child under 5 years age: Questionnaire survey
4. Results of the Study
4.1. IAP Reduction
1.1. Sixty three (63.2 %) percent in PM2.5 and Sixty (60 %) percent reduction in CO in ICS (which was used for one year) was estimated. In terms of absolute value, the Indoor PM2.5 reduced from 2.06 mg/m3 during TCS use to 0.76mg/m3 in ICS. Like wise, CO level was 8.62 ppm in ICS from 21.55 ppm in TCS.
1.2. Comparing the IAP level in Kitchen between ICS use after 3 months and 1 year shows no significant change (P>0.05) in mean concentration.
4.2. Health Impact
The prevalence of acute respiratory symptoms like coughing, phlegm, both cough and phlegm, chest whistling/wheezing etc were low during ICS use than TCS use in Mothers and Child. For instance, the episode of cough in mothers was reduced from 55.6% reduced to 36.1% in ICS after one year of use. Likewise, the episode of phlegm reduced to 44.4 % from 69.4%. One of the important indicators of health impact i.e. eye irritation decreased from 75% to 22.2% in mothers.
5. Lessons Learned
- Although significant reduction was seen in IAP level, the IAP levels are still higher than the WHO guidelines values.
- Ventilation plays are important role in reducing indoor air level, beside ICS. Ventilation co-efficient was higher in Ilam and as a result the IAP levels measured in the stoves of Ilam are lower than the IAP level measured in Dolakha that had low ventilation co-efficient.
- Backfire problem in ICS is frequent. Therefore proper orientation of stove and wind direction in the kitchen should be taken into consideration to avoid this problem.
- Handling of ICS and regular cleaning of the chimney and stove played an essential for the efficient functioning of the stove.
6. Conclusion and Recommendation
This study showed that the two pot hole mud ICS is an effective rural intervention to reduce indoor air pollution in kitchens of rural Nepal. It is cheap, easy to build with a local material and local stove maker and thus suited as one of the most feasible intervention to be promoted throughout Nepal to save the lives of rural women and their children. But to realize the full benefits of a smoke free kitchen, the need for good ventilation, proper operation and maintenance of stoves, and good kitchen management practices also should be highlighted.
Acknowledgement
Participating households, Regional Renewable Energy Service Centers and Alternative Energy Promotion Centre /Energy Sector Assistant Program (www.aepc.gov.np), CEIHD
