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Background: Relatively clean cooking fuels such as liquefied petroleum gas (LPG) emit less fine particulate matter (PM 2·5 ) and carbon monoxide (CO) than polluting fuels (eg, wood, charcoal). Yet, some clean cooking interventions have not achieved substantial exposure reductions. This study evaluates determinants of between-community variability in exposures to household air pollution (HAP) across sub-Saharan Africa., Methods: In this measurement study, we recruited households cooking primarily with LPG or exclusively with wood or charcoal in peri-urban Cameroon, Ghana, and Kenya from previously surveyed households. In 2019-20, we conducted monitoring of 24 h PM 2·5 and CO kitchen concentrations (n=256) and female cook (n=248) and child (n=124) exposures. PM 2·5 measurements used gravimetric and light scattering methods. Stove use monitoring and surveys on cooking characteristics and ambient air pollution exposure (eg, walking time to main road) were also administered., Findings: The mean PM 2·5 kitchen concentration was five times higher among households cooking with charcoal than those using LPG in the Kenyan community (297 μg/m 3 , 95% CI 216-406, vs 61 μg/m 3 , 49-76), but only 4 μg/m 3 higher in the Ghanaian community (56 μg/m 3 , 45-70, vs 52 μg/m 3 , 40-68). The mean CO kitchen concentration in charcoal-using households was double the WHO guideline (6·11 parts per million [ppm]) in the Kenyan community (15·81 ppm, 95% CI 8·71-28·72), but below the guideline in the Ghanaian setting (1·77 ppm, 1·04-2·99). In all communities, mean PM 2·5 cook exposures only met the WHO interim-1 target (35 μg/m 3 ) among LPG users staying indoors and living more than 10 min walk from a road., Interpretation: Community-level variation in the relative difference in HAP exposures between LPG and polluting cooking fuel users in peri-urban sub-Saharan Africa might be attributed to differences in ambient air pollution levels. Thus, mitigation of indoor and outdoor PM 2·5 sources will probably be critical for obtaining significant exposure reductions in rapidly urbanising settings of sub-Saharan Africa., Funding: UK National Institute for Health and Care Research., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: Approximately 2·8 billion people are exposed to household air pollution from cooking with polluting fuels. Few monitoring studies have systematically measured health-damaging air pollutant (ie, fine particulate matter [PM 2·5 ] and black carbon) concentrations from a wide range of cooking fuels across diverse populations. This multinational study aimed to assess the magnitude of kitchen concentrations and personal exposures to PM 2·5 and black carbon in rural communities with a wide range of cooking environments., Methods: As part of the Prospective Urban and Rural Epidemiological (PURE) cohort, the PURE-AIR study was done in 120 rural communities in eight countries (Bangladesh, Chile, China, Colombia, India, Pakistan, Tanzania, and Zimbabwe). Data were collected from 2541 households and from 998 individuals (442 men and 556 women). Gravimetric (or filter-based) 48 h kitchen and personal PM 2·5 measurements were collected. Light absorbance (10 -5 m -1 ) of the PM 2·5 filters, a proxy for black carbon concentrations, was calculated via an image-based reflectance method. Surveys of household characteristics and cooking patterns were collected before and after the 48 h monitoring period., Findings: Monitoring of household air pollution for the PURE-AIR study was done from June, 2017, to September, 2019. A mean PM 2·5 kitchen concentration gradient emerged across primary cooking fuels: gas (45 μg/m 3 [95% CI 43-48]), electricity (53 μg/m 3 [47-60]), coal (68 μg/m 3 [61-77]), charcoal (92 μg/m 3 [58-146]), agricultural or crop waste (106 μg/m 3 [91-125]), wood (109 μg/m 3 [102-118]), animal dung (224 μg/m 3 [197-254]), and shrubs or grass (276 μg/m 3 [223-342]). Among households cooking primarily with wood, average PM 2·5 concentrations varied ten-fold (range: 40-380 μg/m 3 ). Fuel stacking was prevalent (981 [39%] of 2541 households); using wood as a primary cooking fuel with clean secondary cooking fuels (eg, gas) was associated with 50% lower PM 2·5 and black carbon concentrations than using only wood as a primary cooking fuel. Similar average PM 2·5 personal exposures between women (67 μg/m 3 [95% CI 62-72]) and men (62 [58-67]) were observed. Nearly equivalent average personal exposure to kitchen exposure ratios were observed for PM 2·5 (0·79 [95% 0·71-0·88] for men and 0·82 [0·74-0·91] for women) and black carbon (0·64 [0·45-0·92] for men and 0·68 [0·46-1·02] for women)., Interpretation: Using clean primary fuels substantially lowers kitchen PM 2·5 concentrations. Importantly, average kitchen and personal PM 2·5 measurements for all primary fuel types exceeded WHO's Interim Target-1 (35 μg/m 3 annual average), highlighting the need for comprehensive pollution mitigation strategies., Funding: Canadian Institutes for Health Research, National Institutes of Health., (Copyright © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)