Assessment of Health Risks Associated with Particulate Matter and Carbon Monoxide Emissions from Biomass Fuels Utilization in Western Kenya

Abstract

Purpose: The use of biomass fuels poses great threats to environmental degradation and public health risk accounting for 32% of the total attributable burden of diseases due to indoor air pollution (IAP) in especially Africa. Heavy reliance on biomass fuels for household energy in Kenya makes the country more vulnerable with 90% of the rural population relying on biomass fuels for domestic purposes. The objective of this study was to assess cooking fuel types and efficiency of improved biomass stoves in fuel consumption in Western, Kenya.
 Methodology: The data were collected through continuous real-time monitoring of kitchen Particulate Matter and Carbon II Oxide concentration for a period of 24 hours using UCB-PATS and CO monitors, questionnaires and time activity budgets. The total target population was 383 households and 204 households were selected as the sample size for HH survey. The sample size was determined using sample size algorithm by Boyd et al. (2014) where a sample size is determined by the sample population size. Selection of households for indoor air monitoring was done through quasi system where there was a predefined criterion from survey data. Tables and means were used to present results.
 Findings: The study found that Hazard quotients (HQ) for both long-term and short-term PM exposure using all stoves were all above 1 implying that health risk is real. During 24-hour cooking duration, three-stone stove using crop residues produced 145.8 times higher PM2.5 compared to RfD (Reference Dose) value while Cheprocket produced 26.4 times higher than PM2.5 RfD. People using solid biomass fuels are likely to experience headaches and running nose by the end of 24-hour period as a result of CO exposure when mud rocket stove, three stone stove and Cheprocket stoves were used. However cooks who use Chepkube stoves are not likely to experience any adverse health effects from CO exposures since the HQs were less than 1 using both wood and crop residues as fuel. The study concluded that, improved biomass stoves provided an overall reduction in pollutant concentration compared to three-stone fire but the local innovation Chepkube stove that has been classified as ungraded stove had the highest pollutant reduction. There is no health risk associated with exposure to peak CO within the 1-hour duration from all biomass stoves monitored in the study area.
 Recommendation: The study recommended that user education is necessary on kitchen practices to reduce overall exposure from improved stove utilization.