Cooking fuels and household air pollution in resource-constrained urban environments: A field assessment

Household air pollution from cooking remains a major public health and climate challenge in low-income urban areas. In Kibera informal settlement in Nairobi, Kenya high population density living in poorly ventilated houses, surrounded with poor waste management and use of charcoal in inefficient stoves and kerosene expose people to harmful emissions. This study assessed household energy use, cooking time, and emissions of carbon monoxide (CO), carbon dioxide (CO 2 ) and fine particulate matter (PM 2.5 ) from cooking with charcoal, kerosene, liquefied petroleum gas (LPG), and electricity under real-world conditions, and explored implications for health and climate policy. Participatory cooking tests of breakfast and dinner were conducted in three households that used all four fuel types identified in a household survey. Real-time measurements of CO, CO 2, and PM 2.5 were taken before, during, and after cooking. Data were analysed using Welch's ANOVA with Games–Howell post hoc tests. Cooking with any fuel resulted into some household air pollution and charcoal and kerosene produced the highest concentrations of the studied gases and particles. LPG and electricity produced low concentrations and there was no significance difference between the two. The household ambient PM 2.5 was 213 μg/m 3 implying that people are living in houses with this pollutant being 14.2 times above the 24-h threshold of 15 μg/m 3 by World Health Organization guidelines. Hence no fuel switch alone will address household air quality in the informal settlement. Transitioning households to clean(er) cooking stackings such as with renewable ecooking, improved charcoal cookstoves and LPG scenario showed the highest reduction of emissions contributing toward Kenya's nationally determined contribution of 32% reduction green house gases emission. Clean(er) cooking stacking aimed at net zero should consider sustainable sourcing of the fuel. There is also need for integration of green spaces for air pollutions removal and reduction of emissions from activities such as burning of waste in open spaces, industrial processes and transport.