Introduction
Indoor air pollution (IAP) remains one of Nepal’s most pervasive yet underprioritized public health challenges. Despite global advancements in reducing household air pollution, Nepal—particularly its rural and low-income populations—continues to grapple with severe health consequences linked to traditional cooking practices, poor ventilation, and socioeconomic disparities. According to the World Health Organization (WHO), Nepal ranks among the top 10 countries globally for deaths attributable to IAP, with over 23,000 annual fatalities. This article synthesizes current research, highlights gaps in policy and practice, and proposes evidence-based strategies to mitigate IAP’s burden on vulnerable populations.
1. The Scope and Sources of Indoor Air Pollution in Nepal
1.1 Primary Contributors to IAP
Biomass Fuel Dependency: Approximately 74% of Nepali households rely on solid fuels (wood, dung, agricultural residues) for cooking, heating, and lighting (National Population and Housing Census, 2021). Biomass combustion in traditional mud stoves (chulos) emits hazardous pollutants, including:
Particulate matter (PM2.5): Concentrations often exceed WHO’s safe limit (25 μg/m³) by 10–20 times in rural kitchens.
Carbon monoxide (CO) and volatile organic compounds (VOCs): Linked to acute and chronic cardiorespiratory diseases.
Urban Indoor Pollution: In cities like Kathmandu, kerosene heaters, incense burning, and poor ventilation in densely packed housing exacerbate PM2.5 exposure.
Biomass Fuel Dependency: Approximately 74% of Nepali households rely on solid fuels (wood, dung, agricultural residues) for cooking, heating, and lighting (National Population and Housing Census, 2021). Biomass combustion in traditional mud stoves (chulos) emits hazardous pollutants, including:
Particulate matter (PM2.5): Concentrations often exceed WHO’s safe limit (25 μg/m³) by 10–20 times in rural kitchens.
Carbon monoxide (CO) and volatile organic compounds (VOCs): Linked to acute and chronic cardiorespiratory diseases.
Urban Indoor Pollution: In cities like Kathmandu, kerosene heaters, incense burning, and poor ventilation in densely packed housing exacerbate PM2.5 exposure.
1.2 Vulnerable Populations
Women and Children: Women spend 3–7 hours daily near stoves, while children under five face heightened risks of pneumonia due to prolonged exposure (Lancet Global Health, 2020).
Economic Disparities: Low-income households lack access to clean energy alternatives, perpetuating a cycle of poverty and disease.
Women and Children: Women spend 3–7 hours daily near stoves, while children under five face heightened risks of pneumonia due to prolonged exposure (Lancet Global Health, 2020).
Economic Disparities: Low-income households lack access to clean energy alternatives, perpetuating a cycle of poverty and disease.
2. Health Implications: Evidence from Nepal-Specific Studies
2.1 Respiratory and Cardiovascular Morbidity
Chronic Obstructive Pulmonary Disease (COPD): A 2019 Nepal Health Research Council (NHRC) study found 21% prevalence of COPD among biomass users, compared to 9% in LPG-using households.
Acute Lower Respiratory Infections (ALRI): IAP contributes to 45% of childhood pneumonia cases in Nepal (WHO, 2023).
Cardiovascular Disease: PM2.5 exposure correlates with elevated blood pressure and ischemic heart disease, particularly in peri-urban areas (Environmental Research, 2021).
Chronic Obstructive Pulmonary Disease (COPD): A 2019 Nepal Health Research Council (NHRC) study found 21% prevalence of COPD among biomass users, compared to 9% in LPG-using households.
Acute Lower Respiratory Infections (ALRI): IAP contributes to 45% of childhood pneumonia cases in Nepal (WHO, 2023).
Cardiovascular Disease: PM2.5 exposure correlates with elevated blood pressure and ischemic heart disease, particularly in peri-urban areas (Environmental Research, 2021).
2.2 Beyond the Lungs: Systemic Effects
Adverse Pregnancy Outcomes: Maternal exposure to IAP increases risks of low birth weight (OR: 1.8) and preterm births (BMJ Global Health, 2022).
Cognitive Development: Children exposed to high PM2.5 levels show 10–15% lower scores in memory and language tests (NHRC, 2020).
Adverse Pregnancy Outcomes: Maternal exposure to IAP increases risks of low birth weight (OR: 1.8) and preterm births (BMJ Global Health, 2022).
Cognitive Development: Children exposed to high PM2.5 levels show 10–15% lower scores in memory and language tests (NHRC, 2020).
3. Current Interventions and Their Limitations
3.1 Clean Cooking Technologies
Improved Cookstoves (ICS): Programs like the Nepal Biogas Support Program have distributed 400,000 ICS units, reducing PM2.5 by 30–50%. However, adoption remains low due to:
Cultural Preferences: Resistance to abandoning traditional stoves for ritual or culinary reasons.
Economic Barriers: High upfront costs (~$50) for ICS or LPG systems.
Biogas Plants: Over 300,000 installations convert animal waste into clean fuel, but scalability is limited by maintenance challenges and livestock dependency.
Improved Cookstoves (ICS): Programs like the Nepal Biogas Support Program have distributed 400,000 ICS units, reducing PM2.5 by 30–50%. However, adoption remains low due to:
Cultural Preferences: Resistance to abandoning traditional stoves for ritual or culinary reasons.
Economic Barriers: High upfront costs (~$50) for ICS or LPG systems.
Biogas Plants: Over 300,000 installations convert animal waste into clean fuel, but scalability is limited by maintenance challenges and livestock dependency.
3.2 Policy Gaps
Weak Implementation: Despite Nepal’s National Rural and Renewable Energy Program, only 28% of households use clean energy for cooking (UNDP, 2023).
Urban-Rural Divide: Urban subsidies for LPG disproportionately benefit wealthier households, leaving rural populations underserved.
Weak Implementation: Despite Nepal’s National Rural and Renewable Energy Program, only 28% of households use clean energy for cooking (UNDP, 2023).
Urban-Rural Divide: Urban subsidies for LPG disproportionately benefit wealthier households, leaving rural populations underserved.
4. Research Priorities and Multidisciplinary Solutions
4.1 Key Areas for Further Study
Longitudinal Cohort Studies: Track IAP’s lifelong health impacts, particularly intergenerational effects.
Behavioral Interventions: Culturally tailored education programs to shift norms around cooking practices.
Technological Innovation: Affordable air quality sensors and solar-powered ventilation systems for low-resource settings.
Longitudinal Cohort Studies: Track IAP’s lifelong health impacts, particularly intergenerational effects.
Behavioral Interventions: Culturally tailored education programs to shift norms around cooking practices.
Technological Innovation: Affordable air quality sensors and solar-powered ventilation systems for low-resource settings.
4.2 Integrative Policy Recommendations
Subsidize Clean Energy: Expand LPG subsidies through progressive pricing models targeting low-income households.
Strengthen Healthcare Systems: Train community health workers to screen for IAP-related conditions in high-risk areas.
Cross-Sector Collaboration: Integrate IAP mitigation into climate action plans (e.g., reducing deforestation for fuelwood).
Subsidize Clean Energy: Expand LPG subsidies through progressive pricing models targeting low-income households.
Strengthen Healthcare Systems: Train community health workers to screen for IAP-related conditions in high-risk areas.
Cross-Sector Collaboration: Integrate IAP mitigation into climate action plans (e.g., reducing deforestation for fuelwood).
5. Conclusion: A Call for Urgent Action
Indoor air pollution in Nepal is not merely an environmental issue but a profound social justice and public health crisis. Medical researchers must prioritize translational studies bridging laboratory findings with community-based solutions. Simultaneously, policymakers must recognize IAP as a critical determinant of Nepal’s disease burden and allocate resources accordingly. By uniting epidemiology, engineering, and advocacy, Nepal can transform households from sites of risk to spaces of health and resilience.
References
World Health Organization (WHO). (2023). Household Air Pollution and Health.
Nepal Health Research Council (NHRC). (2019). National Burden of Disease Study.
UNDP Nepal. (2023). Energy Access and Equity Report.
Lancet Global Health. (2020). Biomass Fuel Use and Cardiopulmonary Health in South Asia.
BMJ Global Health. (2022). Pregnancy Outcomes and Household Air Pollution in Low-Income Countries.
