Household concentrations and female and child exposures to air pollution in peri-urban sub-Saharan Africa: measurements from the CLEAN-Air(Africa) study.

BACKGROUND: Relatively clean cooking fuels such as liquefied petroleum gas (LPG) emit less fine particulate matter (PM2·5) 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 PM2·5 and CO kitchen concentrations (n=256) and female cook (n=248) and child (n=124) exposures. PM2·5 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 PM2·5 kitchen concentration was five times higher among households cooking with charcoal than those using LPG in the Kenyan community (297 µg/m3, 95% CI 216-406, vs 61 µg/m3, 49-76), but only 4 µg/m3 higher in the Ghanaian community (56 µg/m3, 45-70, vs 52 µg/m3, 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 PM2·5 cook exposures only met the WHO interim-1 target (35 µg/m3) 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 PM2·5 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.

Estimated health effects from domestic use of gaseous fuels for cooking and heating in high-income, middle-income, and low-income countries: a systematic review and meta-analyses.

BACKGROUND: Exposure to household air pollution from polluting domestic fuel (solid fuel and kerosene) represents a substantial global public health burden and there is an urgent need for rapid transition to clean domestic fuels. Gas for cooking and heating might possibly affect child asthma, wheezing, and respiratory health. The aim of this review was to synthesise the evidence on the health effects of gaseous fuels to inform policies for scalable clean household energy. METHODS: In this systematic review and meta-analysis, we summarised the health effects from cooking or heating with gas compared with polluting fuels (eg, wood or charcoal) and clean energy (eg, electricity and solar energy). We searched PubMed, Scopus, Web of Science, MEDLINE, Cochrane Library (CENTRAL), Environment Complete, GreenFile, Google Scholar, Wanfang DATA, and CNKI for articles published between Dec 16, 2020, and Feb 6, 2021. Studies eligible for inclusion had to compare gas for cooking or heating with polluting fuels (eg, wood or charcoal) or clean energy (eg, electricity or solar energy) and present data for health outcomes in general populations. Studies that reported health outcomes that were exacerbations of existing underlying conditions were excluded. Several of our reviewers were involved in screening studies, data extraction, and quality assessment (including risk of bias) of included studies; 20% of studies were independently screened, extracted and quality assessed by another reviewer. Disagreements were reconciled through discussion with the wider review team. Included studies were appraised for quality using the Liverpool Quality Assessment Tools. Key health outcomes were grouped for meta-analysis and analysed using Cochrane's RevMan software. Primary outcomes were health effects (eg, acute lower respiratory infections) and secondary outcomes were health symptoms (eg, respiratory symptoms such as wheeze, cough, or breathlessness). This study is registered with PROSPERO, CRD42021227092. FINDINGS: 116 studies were included in the meta-analysis (two [2%] randomised controlled trials, 13 [11%] case-control studies, 23 [20%] cohort studies, and 78 [67%] cross-sectional studies), contributing 215 effect estimates for five grouped health outcomes. Compared with polluting fuels, use of gas significantly lowered the risk of pneumonia (OR 0·54, 95% CI 0·38-0·77; p=0·00080), wheeze (OR 0·42, 0·30-0·59; p<0·0001), cough (OR 0·44, 0·32-0·62; p<0·0001), breathlessness (OR 0·40, 0·21-0·76; p=0·0052), chronic obstructive pulmonary disease (OR 0·37, 0·23-0·60; p<0·0001), bronchitis (OR 0·60, 0·43-0·82; p=0·0015), pulmonary function deficit (OR 0·27, 0·17-0·44; p<0·0001), severe respiratory illness or death (OR 0·27, 0·11-0·63; p=0·0024), preterm birth (OR 0·66, 0·45-0·97; p=0·033), and low birth weight (OR 0·70, 0·53-0·93; p=0·015). Non-statistically significant effects were observed for asthma in children (OR 1·04, 0·70-1·55; p=0·84), asthma in adults (OR 0·65, 0·43-1·00; p=0·052), and small for gestational age (OR 1·04, 0·89-1·21; p=0·62). Compared with electricity, use of gas significantly increased risk of pneumonia (OR 1·26, 1·03-1·53; p=0·025) and chronic obstructive pulmonary disease (OR 1·15, 1·06-1·25; p=0·0011), although smaller non-significant effects were observed for higher-quality studies. In addition, a small increased risk of asthma in children was not significant (OR 1·09, 0·99-1·19; p=0·071) and no significant associations were found for adult asthma, wheeze, cough, and breathlessness (p>0·05). A significant decreased risk of bronchitis was observed (OR 0·87, 0·81-0·93; p<0·0001). INTERPRETATION: Switching from polluting fuels to gaseous household fuels could lower health risk and associated morbidity and mortality in resource-poor countries where reliance on polluting fuels is greatest. Although gas fuel use was associated with a slightly higher risk for some health outcomes compared with electricity, gas is an important transitional option for health in countries where access to reliable electricity supply for cooking or heating is not feasible in the near term. FUNDING: WHO.

Multiple aspects of energy poverty are associated with lower mental health-related quality of life: A modelling study in three peri-urban African communities.

Objective: Over 900 million people in sub-Saharan Africa (SSA) live in energy poverty, relying on cooking polluting fuels (e.g. wood, charcoal). The association between energy poverty and mental/physical health-related quality of life (HRQoL) among women in SSA, who are primarily tasked with cooking, is unknown. Methods: Females (n â€‹= â€‹1,150) from peri-urban Cameroon, Kenya and Ghana were surveyed on their household energy use and mental/physical health status using the standardized Short-Form 36 (SF-36) questionnaire. Random effects linear regression linked household energy factors to SF-36 mental (MCS) and physical component summary (PCS) scores. A binary outcome of 'likely depression' was derived based on participants' MCS score. Random effects Poisson regression with robust error variance assessed the relationship between household energy factors and odds of likely depression. Results: The prevalence of likely depression varied by a factor of four among communities (36%-Mbalmayo, Cameroon; 20%-Eldoret, Kenya; 9%-Obuasi, Ghana). In the Poisson model (coefficient of determination (R2) â€‹= â€‹0.28), females sustaining 2 or more cooking-related burns during the previous year had 2.7 (95%CI:[1.8,4.1]) times the odds of likely depression as those not burned. Females cooking primarily with charcoal and wood had 1.6 times (95%CI:[0.9,2.7]) and 1.5 times (95%CI:[0.8,3.0]) the odds of likely depression, respectively, as those primarily using liquefied petroleum gas. Women without electricity access had 1.4 (95%CI:[1.1,1.9]) times the odds of likely depression as those with access. In the MCS model (R2 â€‹= â€‹0.23), longer time spent cooking was associated with a lower average MCS score in a monotonically increasing manner. In the PCS model (R2 â€‹= â€‹0.32), women injured during cooking fuel collection had significantly lower (-4.8 95%CI:[-8.1,-1.4]) PCS scores. Conclusion: The burden of energy poverty in peri-urban communities in SSA extends beyond physical conditions. Experiencing cooking-related burns, using polluting fuels for cooking or lighting and spending more time cooking are potential risk factors for lower mental HRQoL among women.