Pre-clinical Measures of Eye Damage (Lens Opacity), Case-control Study of Tuberculosis, and Indicators of Indoor Air Pollution from Biomass Smoke
- Author(s): Pokhrel, Amod Kumar
- Advisor(s): Smith, Kirk R
- Bates, Michael N
- et al.
This dissertation examines the level of two major pollutants in the kitchens from biomass, kerosene and liquefied petroleum gas (LPG) stoves, and two health problems associated with use of biomass and kerosene compared with LPG stove in Nepal. Its chapter a) characterizes the exposure levels of two pollutants-fine particles (PM2.5) and naphthalene from three cookstoves, b) validate exposure questionnaire used in two epidemiological studies with the gold standard, c) showcase method to estimate sample size (duration of measurements) to reliably characterize levels of PM2.5 across rural households from continuously measured PM2.5 data, and d) examines the association of use of biomass and kerosene fuel with pre-clinical damage of lens (lens opacity) and tuberculosis in women.
Divided on 5 chapters, the chapter 1 gives an overview of the dissertation. Chapter 2 provides a detailed background, materials and methods and results of validity study, and measurement results of naphthalene and PM2.5 from passive samplers. Similarly chapter 2 validates method for determining sample size from continuously measured PM2.5 data. Although there exist studies of associations of TB and cataracts from use of biomass fuel but the possible associations of TB and cataracts with the use of kerosene fuel are virtually uninvestigated. Chapter 3 investigates association between biomass and kerosene fuel use and pre-clinical damage of lens (lens opacity) in women and chapter 4 investigates the association between biomass and kerosene fuel use and TB in women. The chapter 5 summarizes the main findings of chapters 2, 3 and 4.
The results of the three main chapters suggest that in Nepal cooks who use unvented biomass cookstoves experience very high mean and peak exposure of PM2.5 compared with kerosene and LPG stoves. By contrast, the cooks experience higher exposure of naphthalene from both kerosene and biomass cookstoves compared with LPG cookstoves. Current and past use of biomass cookstoves is associated with an increase risk of nuclear opacity and use of biomass as a heating fuel and kerosene, either in stoves or in lamps, is a risk factor for TB. Thus, promotion of low-emission biomass stoves, such as semi-gasifier stoves or other cleaner burning fuels (biogas or LPG) for cooking and heating, and promotion of solar lamps or cleaner burning devises for lighting could minimize the risk of lens opacity and TB in women in rural areas of Nepal.