In praise of cooking gas subsidies: transitional fuels to advance health and equity.

Households that burn biomass in inefficient open fires-a practice that results in $1.6 trillion in global damages from health impacts and climate-altering emissions yearly-are often unable to access cleaner alternatives, like gas, which is widely available but unaffordable, or electricity, which is unattainable for many due to insufficient supply and reliability of electricity services. Governments are often reluctant to make gas affordable. We argue that condemnation of all fossil fuel subsidies is short-sighted and does not adequately consider subsidizing gas for cooking as a potential strategy to improve public health and reduce greenhouse gas emissions.

Prenatal Household Air Pollution Exposure and Childhood Blood Pressure in Rural Ghana.

BACKGROUND: The association between prenatal household air pollution (HAP) exposure and childhood blood pressure (BP) is unknown. OBJECTIVE: Within the Ghana Randomized Air Pollution and Health Study (GRAPHS) we examined time-varying associations between a) maternal prenatal and b) first-year-of-life HAP exposure with BP at 4 years of age and, separately, whether a stove intervention delivered prenatally and continued through the first year of life could improve BP at 4 years of age. METHODS: GRAPHS was a cluster-randomized cookstove intervention trial wherein n=1,414 pregnant women were randomized to one of two stove interventions: a) a liquefied petroleum gas (LPG) stove or improved biomass stove, or b) control (open fire cooking). Maternal HAP exposure over pregnancy and child HAP exposure over the first year of life was quantified by repeated carbon monoxide (CO) measurements; a subset of women (n=368) also performed one prenatal and one postnatal personal fine particulate matter (PM2.5) measurement. Systolic and diastolic BP (SBP and DBP) were measured in n=667 4-y-old children along with their PM2.5 exposure (n=692). We examined the effect of the intervention on resting BP z-scores. We also employed reverse distributed lag models to examine time-varying associations between a) maternal prenatal and b) first-year-of-life HAP exposure and resting BP z-scores. Among those with PM2.5 measures, we examined associations between PM2.5 and resting BP z-scores. Sex-specific effects were considered. RESULTS: Intention-to-treat analyses identified that DBP z-score at 4 years of age was lower among children born in the LPG arm (LPG ß=-0.20; 95% CI: -0.36, -0.03) as compared with those in the control arm, and females were most susceptible to the intervention. Higher CO exposure in late gestation was associated with higher SBP and DBP z-score at 4 years of age, whereas higher late-first-year-of-life CO exposure was associated with higher DBP z-score. In the subset with PM2.5 measurements, higher maternal postnatal PM2.5 exposure was associated with higher SBP z-scores. DISCUSSION: These findings suggest that prenatal and first-year-of-life HAP exposure are associated with child BP and support the need for reductions in exposure to HAP, with interventions such as cleaner cooking beginning in pregnancy. https://doi.org/10.1289/EHP13225.

In praise of fossil fuel subsidies (for cooking).

Households that burn biomass in inefficient open fires - a practice that results in $1.6 trillion in global damages from health impacts and climate-altering emissions yearly - are often unable to access cleaner alternatives, like gas, which is widely available but unaffordable, or electricity, which is unattainable for many due to insufficient supply and reliability of electricity services. Governments are often reluctant to make gas affordable. We argue that condemnation of all fossil fuel subsidies is short-sighted and does not adequately consider subsidizing gas for cooking as a potential strategy to improve public health and reduce greenhouse gas emissions.

Health Effects of Wildfire Smoke Exposure.

We review current knowledge on the trends and drivers of global wildfire activity, advances in the measurement of wildfire smoke exposure, and evidence on the health effects of this exposure. We describe methodological issues in estimating the causal effects of wildfire smoke exposures on health and quantify their importance, emphasizing the role of nonlinear and lagged effects. We conduct a systematic review and meta-analysis of the health effects of wildfire smoke exposure, finding positive impacts on all-cause mortality and respiratory hospitalizations but less consistent evidence on cardiovascular morbidity. We conclude by highlighting priority areas for future research, including leveraging recently developed spatially and temporally resolved wildfire-specific ambient air pollution data to improve estimates of the health effects of wildfire smoke exposure.

The contribution of wildfire to PM2.5 trends in the USA.

Steady improvements in ambient air quality in the USA over the past several decades, in part a result of public policy1,2, have led to public health benefits1-4. However, recent trends in ambient concentrations of particulate matter with diameters less than 2.5 µm (PM2.5), a pollutant regulated under the Clean Air Act1, have stagnated or begun to reverse throughout much of the USA5. Here we use a combination of ground- and satellite-based air pollution data from 2000 to 2022 to quantify the contribution of wildfire smoke to these PM2.5 trends. We find that since at least 2016, wildfire smoke has influenced trends in average annual PM2.5 concentrations in nearly three-quarters of states in the contiguous USA, eroding about 25% of previous multi-decadal progress in reducing PM2.5 concentrations on average in those states, equivalent to 4 years of air quality progress, and more than 50% in many western states. Smoke influence on trends in the number of days with extreme PM2.5 concentrations is detectable by 2011, but the influence can be detected primarily in western and mid-western states. Wildfire-driven increases in ambient PM2.5 concentrations are unregulated under current air pollution law6 and, in the absence of further interventions, we show that the contribution of wildfire to regional and national air quality trends is likely to grow as the climate continues to warm.

Emergency department visits respond nonlinearly to wildfire smoke.

Air pollution negatively affects a range of health outcomes. Wildfire smoke is an increasingly important contributor to air pollution, yet wildfire smoke events are highly salient and could induce behavioral responses that alter health impacts. We combine geolocated data covering all emergency department (ED) visits to nonfederal hospitals in California from 2006 to 2017 with spatially resolved estimates of daily wildfire smoke PM[Formula: see text] concentrations and quantify how smoke events affect ED visits. Total ED visits respond nonlinearly to smoke concentrations. Relative to a day with no smoke, total visits increase by 1 to 1.5% in the week following low or moderate smoke days but decline by 6 to 9% following extreme smoke days. Reductions persist for at least a month. Declines at extreme levels are driven by diagnoses not thought to be acutely impacted by pollution, including accidental injuries and several nonurgent symptoms, and declines come disproportionately from less-insured populations. In contrast, health outcomes with the strongest physiological link to short-term air pollution increase dramatically in the week following an extreme smoke day: We estimate that ED visits for asthma, COPD, and cough all increase by 30 to 110%. Data from internet searches, vehicle traffic sensors, and park visits indicate behavioral changes on high smoke days consistent with declines in healthcare utilization. Because low and moderate smoke days vastly outweigh high smoke days, we estimate that smoke was responsible for an average of 3,010 (95% CI: 1,760-4,380) additional ED visits per year 2006 to 2017. Given the increasing intensity of wildfire smoke events, behavioral mediation is likely to play a growing role in determining total smoke impacts.

Climate and health benefits of a transition from gas to electric cooking.

Household electrification is thought to be an important part of a carbon-neutral future and could also have additional benefits to adopting households such as improved air quality. However, the effectiveness of specific electrification policies in reducing total emissions and boosting household livelihoods remains a crucial open question in both developed and developing countries. We investigated a transition of more than 750,000 households from gas to electric cookstoves-one of the most popular residential electrification strategies-in Ecuador following a program that promoted induction stoves and assessed its impacts on electricity consumption, greenhouse gas emissions, and health. We estimate that the program resulted in a 5% increase in total residential electricity consumption between 2015 and 2021. By offsetting a commensurate amount of cooking gas combustion, we find that the program likely reduced national greenhouse gas emissions, thanks in part to the country's electricity grid being 80% hydropower in later parts of the time period. Increased induction stove uptake was also associated with declines in all-cause and respiratory-related hospitalizations nationwide. These findings suggest that, when the electricity grid is largely powered by renewables, gas-to-induction cooking transitions represent a promising way of amplifying the health and climate cobenefits of net-carbon-zero policies.

Resilient clean cooking: Maintaining household clean cooking in Ecuador during the COVID-19 pandemic.

Decades of government subsidies for LPG and electricity have facilitated near-universal clean cooking access and use in Ecuador, placing the nation ahead of most other peer low- and middle-income countries. The widespread socio-economic impacts of the COVID-19 pandemic has threatened the resilience of clean cooking systems globally, including by altering households' ability to purchase clean fuels and policymakers' considerations about continuing subsidy programs. As such, assessing the resilience of clean cooking in Ecuador during the pandemic can offer important lessons for the international community, especially other countries looking to ensure resilient transitions to clean cooking. We study household energy use patterns using interviews, newspaper reports, government data on household electricity and LPG consumption, and household surveys [N = 200 across two rounds]. The LPG and electricity distribution systems experienced occasional disruptions to cylinder refill delivery and meter reading processes, respectively, which were associated with pandemic-related mobility restrictions. However, for the most part, supply and distribution activities by private and public companies continued without fundamental change. Survey participants reported increases in unemployment and reductions in household income as well as increased use of polluting biomass as a secondary fuel. Ecuador's LPG and electricity distribution systems were resilient throughout the pandemic, with only minimal interruption of the widespread provision of low-cost clean cooking fuels. Our findings inform the global audience concerned about the resilience of clean household energy use on the potential for clean fuel subsidies to facilitate continued clean cooking even during the COVID-19 pandemic.

Widespread Clean Cooking Fuel Scale-Up and under-5 Lower Respiratory Infection Mortality: An Ecological Analysis in Ecuador, 1990-2019.

BACKGROUND: Nationwide household transitions to the use of clean-burning cooking fuels are a promising pathway to reducing under-5 lower respiratory infection (LRI) mortality, the leading cause of child mortality globally, but such transitions are rare and evidence supporting an association between increased clean fuel use and improved health is limited. OBJECTIVES: This study aimed to investigate the association between increased primary clean cooking fuel use and under-5 LRI mortality in Ecuador between 1990 and 2019. METHODS: We documented cooking fuel use and cause-coded child mortalities at the canton (county) level in Ecuador from 1990 to 2019 (in four periods, 1988-1992, 1999-2003, 2008-2012, and 2015-2019). We characterized the association between clean fuel use and the rate of under-5 LRI mortalities at the canton level using quasi-Poisson generalized linear and generalized additive models, accounting for potential confounding variables that characterize wealth, urbanization, and child health care and vaccination rates, as well as canton and period fixed effects. We estimated averted under-5 LRI mortalities accrued over 30 y by predicting a counterfactual count of canton-period under-5 LRI mortalities were clean fuel use to not have increased and comparing with predicted canton-period under-5 LRI mortalities from our model and observed data. RESULTS: From 1990 to 2019, the proportion of households primarily using a clean cooking fuel increased from 59% to 95%, and under-5 LRI mortality fell from 28 to 7 per 100,000 under-5 population. Canton-level clean fuel use was negatively associated with under-5 LRI mortalities in linear and nonlinear models. The nonlinear association suggested a threshold at approximately 60% clean fuel use, above which there was a negative association. Increases in clean fuel use between 1990 and 2019 were associated with an estimated 7,300 averted under-5 LRI mortalities (95% confidence interval: 2,600, 12,100), accounting for nearly 20% of the declines in under-5 LRI mortality observed in Ecuador over the study period. DISCUSSION: Our findings suggest that the widespread household transition from using biomass to clean-burning fuels for cooking reduced under-5 LRI mortalities in Ecuador over the last 30 y. https://doi.org/10.1289/EHP11016.

Using time-resolved monitor wearing data to study the effect of clean cooking interventions on personal air pollution exposures.

BACKGROUND: Personal monitoring can estimate individuals' exposures to environmental pollutants; however, accuracy depends on consistent monitor wearing, which is under evaluated. OBJECTIVE: To study the association between device wearing and personal air pollution exposure. METHODS: Using personal device accelerometry data collected in the context of a randomized cooking intervention in Ghana with three study arms (control, improved biomass, and liquified petroleum gas (LPG) arms; N = 1414), we account for device wearing to infer parameters of PM2.5 and CO exposure. RESULTS: Device wearing was positively associated with exposure in the control and improved biomass arms, but weakly in the LPG arm. Inferred community-level air pollution was similar across study arms (~45 µg/m3). The estimated direct contribution of individuals' cooking to PM2.5 exposure was 64 µg/m3 for the control arm, 74 µg/m3 for improved biomass, and 6 µg/m3 for LPG. Arm-specific average PM2.5 exposure at near-maximum wearing was significantly lower in the LPG arm as compared to the improved biomass and control arms. Analysis of personal CO exposure mirrored PM2.5 results. CONCLUSIONS: Personal monitor wearing was positively associated with average air pollution exposure, emphasizing the importance of high device wearing during monitoring periods and directly assessing device wearing for each deployment. SIGNIFICANCE: We demonstrate that personal monitor wearing data can be used to refine exposure estimates and infer unobserved parameters related to the timing and source of environmental exposures. IMPACT STATEMENTS: In a cookstove trial among pregnant women, time-resolved personal air pollution device wearing data were used to refine exposure estimates and infer unobserved exposure parameters, including community-level air pollution, the direct contribution of cooking to personal exposure, and the effect of clean cooking interventions on personal exposure. For example, in the control arm, while average 48 h personal PM2.5 exposure was 77 µg/m3, average predicted exposure at near-maximum daytime device wearing was 108 µg/m3 and 48 µg/m3 at zero daytime device wearing. Wearing-corrected average 48 h personal PM2.5 exposures were 50% lower in the LPG arm than the control and improved biomass and inferred direct cooking contributions to personal PM2.5 from LPG were 90% lower than the other arms. Our recommendation is that studies assessing personal exposures should examine the direct association between device wearing and estimated mean personal exposure.

Daily Local-Level Estimates of Ambient Wildfire Smoke PM2.5 for the Contiguous US.

Smoke from wildfires is a growing health risk across the US. Understanding the spatial and temporal patterns of such exposure and its population health impacts requires separating smoke-driven pollutants from non-smoke pollutants and a long time series to quantify patterns and measure health impacts. We develop a parsimonious and accurate machine learning model of daily wildfire-driven PM2.5 concentrations using a combination of ground, satellite, and reanalysis data sources that are easy to update. We apply our model across the contiguous US from 2006 to 2020, generating daily estimates of smoke PM2.5 over a 10 km-by-10 km grid and use these data to characterize levels and trends in smoke PM2.5. Smoke contributions to daily PM2.5 concentrations have increased by up to 5 µg/m3 in the Western US over the last decade, reversing decades of policy-driven improvements in overall air quality, with concentrations growing fastest for higher income populations and predominantly Hispanic populations. The number of people in locations with at least 1 day of smoke PM2.5 above 100 µg/m3 per year has increased 27-fold over the last decade, including nearly 25 million people in 2020 alone. Our data set can bolster efforts to comprehensively understand the drivers and societal impacts of trends and extremes in wildfire smoke.

Exposures and behavioural responses to wildfire smoke.

Pollution from wildfires constitutes a growing source of poor air quality globally. To protect health, governments largely rely on citizens to limit their own wildfire smoke exposures, but the effectiveness of this strategy is hard to observe. Using data from private pollution sensors, cell phones, social media posts and internet search activity, we find that during large wildfire smoke events, individuals in wealthy locations increasingly search for information about air quality and health protection, stay at home more and are unhappier. Residents of lower-income neighbourhoods exhibit similar patterns in searches for air quality information but not for health protection, spend less time at home and have more muted sentiment responses. During smoke events, indoor particulate matter (PM2.5) concentrations often remain 3-4× above health-based guidelines and vary by 20× between neighbouring households. Our results suggest that policy reliance on self-protection to mitigate smoke health risks will have modest and unequal benefits.

Poor early childhood growth is associated with impaired lung function: Evidence from a Ghanaian pregnancy cohort.

OBJECTIVES: Nearly 40% of African children under 5 are stunted. We leveraged the Ghana randomized air pollution and health study (GRAPHS) cohort to examine whether poorer growth was associated with worse childhood lung function. STUDY DESIGN: GRAPHS measured infant weight and length at birth and 3, 6, 9,12 months, and 4 years of age. At age 4 years, n = 567 children performed impulse oscillometry. We employed multivariable linear regression to estimate associations between birth and age 4 years anthropometry and lung function. Next, we employed latent class growth analysis (LCGA) to generate growth trajectories through age 4 years. We employed linear regression to examine associations between growth trajectory assignment and lung function. RESULTS: Birth weight and age 4 weight-for-age and height-for-age z-scores were inversely associated with airway resistance (e.g., R5 , or total airway resistance: birth weight ß = -0.90 cmH2O/L/s, 95% confidence interval [CI]: -1.64, -0.16 per 1 kg increase; and R20 , or large airway resistance: age 4 height-for-age ß = -0.40 cmH2O/L/s, 95% CI: -0.57, -0.22 per 1 unit z-score increase). Impaired growth trajectories identified through LCGA were associated with higher airway resistance, even after adjusting for age 4 body mass index. For example, children assigned to a persistently stunted trajectory had higher R5 (ß = 2.71 cmH2O/L/s, 95% CI: 1.07, 4.34) and R20 (ß = 1.43 cmH2O/L/s, 95% CI: 0.51, 2.36) as compared to normal. CONCLUSION: Children with poorer anthropometrics through to age 4 years had higher airway resistance in early childhood. These findings have implications for lifelong lung health, including pneumonia risk in childhood and reduced maximally attainable lung function in adulthood.

Environmental Factors Influencing COVID-19 Incidence and Severity.

Emerging evidence supports a link between environmental factors-including air pollution and chemical exposures, climate, and the built environment-and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission and coronavirus disease 2019 (COVID-19) susceptibility and severity. Climate, air pollution, and the built environment have long been recognized to influence viral respiratory infections, and studies have established similar associations with COVID-19 outcomes. More limited evidence links chemical exposures to COVID-19. Environmental factors were found to influence COVID-19 through four major interlinking mechanisms: increased risk of preexisting conditions associated with disease severity; immune system impairment; viral survival and transport; and behaviors that increase viral exposure. Both data and methodologic issues complicate the investigation of these relationships, including reliance on coarse COVID-19 surveillance data; gaps in mechanistic studies; and the predominance of ecological designs. We evaluate the strength of evidence for environment-COVID-19 relationships and discuss environmental actions that might simultaneously address the COVID-19 pandemic, environmental determinants of health, and health disparities.

Corrigendum to "Prenatal household air pollutant exposure is associated with reduced size and gestational age at birth among a cohort of Ghanaian infants" [Environ. Int. 155 (2021) 106659].

[This corrects the article PMC8628363.].

Prenatal and Postnatal Household Air Pollution Exposure and Infant Growth Trajectories: Evidence from a Rural Ghanaian Pregnancy Cohort.

BACKGROUND: The exposure-response association between prenatal and postnatal household air pollution (HAP) and infant growth trajectories is unknown. OBJECTIVES: To evaluate associations between prenatal and postnatal HAP exposure and stove interventions on growth trajectories over the first year of life. METHODS: The Ghana Randomized Air Pollution and Health Study enrolled n=1,414 pregnant women at ≤24wk gestation from Kintampo, Ghana, and randomized them to liquefied petroleum gas (LPG), improved biomass, or open fire (control) stoves. We quantified HAP exposure by repeated, personal prenatal and postnatal carbon monoxide (CO) and, in a subset, fine particulate matter [PM with an aerodynamic diameter of ≤2.5µm (PM2.5)] assessments. Length, weight, mid-upper arm circumference (MUAC) and head circumference (HC) were measured at birth, 3, 6, 9, and 12 months; weight-for-age, length-for-age (LAZ), and weight-for-length z (WLZ)-scores were calculated. For each anthropometric measure, we employed latent class growth analysis to generate growth trajectories over the first year of life and assigned each child to a trajectory group. We then employed ordinal logistic regression to determine associations between HAP exposures and growth trajectory assignments. Associations with stove intervention arm were also considered. RESULTS: Of the 1,306 live births, 1,144 had valid CO data and anthropometric variables measured at least once. Prenatal HAP exposure increased risk for lower length [CO odds ratio (OR)= 1.17, 95% CI: 1.01, 1.35 per 1-ppm increase; PM2.5 OR= 1.07, 95% CI: 1.02, 1.13 per 10-µg/m3 increase], lower LAZ z-score (CO OR= 1.15, 95% CI: 1.01, 1.32 per 1-ppm increase) and stunting (CO OR= 1.25, 95% CI: 1.08, 1.45) trajectories. Postnatal HAP exposure increased risk for smaller HC (CO OR= 1.09, 95% CI: 1.04, 1.13 per 1-ppm increase), smaller MUAC and lower WLZ-score (PM2.5 OR= 1.07, 95% CI: 1.00, 1.14 and OR= 1.09, 95% CI: 1.01, 1.19 per 10-µg/m3 increase, respectively) trajectories. Infants in the LPG arm had decreased odds of having smaller HC and MUAC trajectories as compared with those in the open fire stove arm (OR= 0.58, 95% CI: 0.37, 0.92 and OR= 0.45, 95% CI: 0.22, 0.90, respectively). DISCUSSION: Higher early life HAP exposure (during pregnancy and through the first year of life) was associated with poorer infant growth trajectories among children in rural Ghana. A cleaner-burning stove intervention may have improved some growth trajectories. https://doi.org/10.1289/EHP8109.

A cluster randomised trial of cookstove interventions to improve infant health in Ghana.

INTRODUCTION: Household air pollution from solid fuel combustion for cooking and heating is a leading cause of childhood morbidity and mortality worldwide. We hypothesised that clean cooking interventions delivered during pregnancy would improve child health. METHODS: We conducted a cluster randomised trial in rural Ghana to test whether providing pregnant women liquefied petroleum gas (LPG) cookstoves or improved biomass cookstoves would reduce personal carbon monoxide and fine particulate pollution exposure, increase birth weight and reduce physician-assessed severe pneumonia in the first 12 months of life, compared with control participants who continued to cook with traditional stoves. Primary analyses were intention-to-treat. The trial was registered with ClinicalTrials.gov and follow-up is complete. RESULTS: Enrolment began on 14 April 2014, and ended on 20 August 2015. We enrolled 1414 pregnant women; 361 in the LPG arm, 527 in the improved biomass cookstove arm and 526 controls. We saw no improvement in birth weight (the difference in mean birth weight for LPG arm births was 29 g lighter (95% CI -113 to 56, p=0.51) and for improved biomass arm births was 9 g heavier (95% CI -64 to 82, p=0.81), compared with control newborns) nor severe child pneumonia (the rate ratio for pneumonia in the LPG arm was 0.98 (95% CI 0.58 to 1.70; p=0.95) and for the improved biomass arm was 1.21 (95% CI 0.78 to 1.90; p=0.52), compared with the control arm). Air pollution exposures in the LPG arm remained above WHO health-based targets (LPG median particulate matter less than 2.5 microns in diameter (PM2.5) 45 µg/m³; IQR 32-65 vs control median PM2.5 67 µg/m³, IQR 46-97). CONCLUSIONS: Neither prenatally-introduced LPG nor improved biomass cookstoves improved birth weight or reduced severe pneumonia risk in the first 12 months of life. We hypothesise that this is due to lower-than-expected exposure reductions in the intervention arms. TRIAL REGISTRATION NUMBER: NCT01335490.

Prenatal household air pollutant exposure is associated with reduced size and gestational age at birth among a cohort of Ghanaian infants.

BACKGROUND: Low birth weight and prematurity are important risk factors for death and disability, and may be affected by prenatal exposure to household air pollution (HAP). METHODS: We investigate associations between maternal exposure to carbon monoxide (CO) during pregnancy and birth outcomes (birth weight, birth length, head circumference, gestational age, low birth weight, small for gestational age, and preterm birth) among 1288 live-born infants in the Ghana Randomized Air Pollution and Health Study (GRAPHS). We evaluate whether evidence of malaria during pregnancy, as determined by placental histopathology, modifies these associations. RESULTS: We observed effects of CO on birth weight, birth length, and gestational age that were modified by placental malarial status. Among infants from pregnancies without evidence of placental malaria, each 1 ppm increase in CO was associated with reduced birth weight (-53.4 g [95% CI: -84.8, -21.9 g]), birth length (-0.3 cm [-0.6, -0.1 cm]), gestational age (-1.0 days [-1.8, -0.2 days]), and weight-for-age Z score (-0.08 standard deviations [-0.16, -0.01 standard deviations]). These associations were not observed in pregnancies with evidence of placental malaria. Each 1 ppm increase in maternal exposure to CO was associated with elevated odds of low birth weight (LBW, OR 1.14 [0.97, 1.33]) and small for gestational age (SGA, OR 1.14 [0.98, 1.32]) among all infants. CONCLUSIONS: Even modest reductions in exposure to HAP among pregnant women could yield substantial public health benefits, underscoring a need for interventions to effectively reduce exposure. Adverse associations with HAP were discernible only among those without evidence of placental malaria, a key driver of impaired fetal growth in this malaria-endemic area.

Firewood, forests, and fringe populations: Exploring the inequitable socioeconomic dimensions of Liquified Petroleum Gas (LPG) adoption in India.

Liquified petroleum gas (LPG) is an important clean fuel alternative for households that rely on burning biomass for daily cooking needs. In India, Pradhan Mantri Ujjwala Yojana (PMUY) has provided poor households with LPG connections since 2016. We investigate cooking fuel use in households to determine the impact of the policy in the Central Indian Highlands Landscape (CIHL). The CIHL has a large population of marginalized social groups, including Indigenous, Scheduled Tribe, Schedule Caste, and Other Backward Caste people. We utilize survey data from 4,994 households within 500 villages living in forested regions collected in 2018 and a satellite-derived measure of forest availability to investigate the household and ecological determinants of LPG adoption and the timing of this adoption (pre- or post-2016). In addition, we document patterns of firewood collection and evaluate the extent to which households acquiring LPG change these activities. The probability of cooking with LPG was lowest for marginalized social groups. We observe that households recently adopting LPG, likely through PMUY, are poorer, more socially marginalized, less educated, and have more forest available nearby than their early-adopter counterparts. While 90% of LPG-using households continue to use firewood, households that have owned LPG for more years report spending less time collecting firewood, indicating a waning reliance on firewood over time. Policies targeting communities with marginalized social groups living near forests can further accelerate LPG adoption and displace firewood use. Despite overall growth in LPG use, disparities in access to clean cooking fuels remain between socioeconomic groups in India.