Kitchen fine particulate matter (PM2.5) concentrations from biomass fuel use in rural households of Northwest Ethiopia

Background: Combustion of solid biomass fuels using traditional stoves which is the daily routine for 3 billion people emits various air pollutants including fine particulate matter which is one of the widely recognized risk factors for various cardiorespiratory and other health problems. But, there is only limited evidences of kitchen PM(2.5 )concentrations in rural Ethiopia.Objective: This study is aimed to estimate the 24-h average kitchen area concentrations of PM2.5 and to identify associated factors in rural households of northwest Ethiopia.Method: The average kitchen area PM(2.5 )concentrations were measured using a low-cost light-scattering Particle and Temperature Sensor Plus (PATS+) for a 24-h sampling period. Data from the PATS+ was downloaded in electronic form for further analysis. Other characteristics were collected using face-to-face interviews. Independent sample t-test and one-way analysis of variance were used to test differences in PM2.5 concentrations between and among various characteristics, respectively.Result Mixed fuels were the most common cooking biomass fuel. The 24-h average kitchen PM(2.5 )concentrations was estimated to be 405 mu g/m(3), ranging from 52 to 965 mu g/m(3). The average concentrations were 639 vs. 336 mu g/m(3) (p < 0.001) in the thatched and corrugated iron sheet roof kitchens, respectively. The average concentration was also higher among mixed fuel users at 493 vs. 347 mu g/m(3) (p = 0.042) compared with firewood users and 493 vs. 233 mu g/m(3) (p = 0.007) as compared with crop residue fuel users. Statistically significant differences were also observed across starter fuel types 613 vs. 343 mu g/m(3) (p = 0.016) for kerosene vs. dried leaves and Injera baking events 523 vs. 343 mu g/m(3) (p < 0.001) for baked vs. not baked events.Conclusion The average kitchen PM2.5 concentrations in the study area exceeded the world health organization indoor air quality guideline value of 15 mu g/m(3) which can put pregnant women at greater risk and contribute to poor pregnancy outcomes. Thatched roof kitchen, mixed cooking fuel, kerosene fire starter, and Injera baking events were positively associated with high-level average kitchen PM2.5. concentration. Simple cost-effective interventions like the use of chimney-fitted improved stoves and sensitizing women about factors that aggravate kitchen PM(2.5 )concentrations could reduce kitchen PM (2.5 )levels in the future.