Household air pollution related to biomass cook stove emissions and its interaction with improved cookstoves

Effects of maternal exposure to biomass cooking fuel on birth size and body proportionality in full-term infants born by vaginal delivery

It remains unclear whether and how maternal exposure to biomass fuel influences infant anthropometry or body proportionality at birth, which are linked to their survival, physical growth, and neurodevelopment. Therefore, this study seeks to explore the association between household-level exposure to biomass cooking fuels and infant size and body proportionality at birth among women in rural Bangladesh. A total of 909 women were derived from the Pregnancy Weight Gain study, which was conducted in Matlab, a rural area of Bangladesh. Infant's weight (g), length (cm), head circumference (cm), small for gestational age (SGAW), short for gestational age (SGAL), low head circumference for gestational age (SGAHC), ponderal index, and cephalization index at birth were the outcomes studied. Of the women, 721 (79.3%) were dependent on biomass fuel. Compared to infants born to mothers who used gas for cooking, those born to biomass users had lower weight (β - 94.3, CI - 155.9, - 32.6), length (β - 0.36, 95% CI - 0.68, - 0.04), head circumference (β - 0.24, CI - 0.47, - 0.02) and higher cephalization index (β 0.03, CI 0.01, 0.05) at birth. Maternal biomass exposure is more likely to lead to symmetric SGA, although there is evidence for some brain-sparing effects.

Global trends and burden of stroke attributable to particulate matter pollution from 1990 to 2019

OBJECTIVE

To investigate the association between particulate matter and the incidence, disability, and mortality of stroke, we reported the burden of stroke attributable to particulate matter (PM2.5) pollution, including ambient particulate matter pollution (APMP) and household air pollution from solid fuels (HAP), from 1990 to 2019.

METHODS

We retrieved the detailed data on the burden of stroke attributable to PM2.5 from the Global Burden of Disease (GBD) 2019. The number of disability-adjusted life-years (DALYs) and deaths, age-standardized death rates (ASMR), and age-standardized disability-adjusted life-years rates (ASDR) attributable to PM2.5 were estimated by age, sex, geographical location, socio-demographic index (SDI), and stroke subtypes (ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage). The estimated annual percentage change (EAPC) was calculated to assess the trends in ASDR and ASMR during the period 1990-2019.

RESULTS

Regarding stroke subtypes, the proportion of ischemic stroke burden is increasing, while intracerebral hemorrhage carries the heaviest burden. Both APMP and HAP contributed the most to stroke-related deaths and DALYs of stroke among the elderly populations and males. The highest ASDR and ASMR of stroke attributable to APMP were in the middle SDI regions, especially in East Asia. For HAP, the highest ASDR and ASMR were in the low SDI regions, mainly in Oceania. From 1990-2019, in terms of the EAPC results, APMP caused an increased burden of stroke, whereas the impact of HAP significantly fell. The most pronounced increase in ASDR and ASMR for strokes attributed to APMP were in the low-middle SDI and low SDI regions, particularly among the 25-35 age group.

CONCLUSIONS

Stroke attributed to PM2.5 is a global health problem, and the patterns and trends were heterogeneous across APMP and HAP. Targeted interventions should be formulated for APMP and HAP.

Association Between Maternal Prenatal Exposure to Household Air Pollution and Child Respiratory Health: A Systematic Review and Meta-analysis

Maternal prenatal exposure to household air pollution (HAP) is a critical public health concern with potential long-term implications for child respiratory health. The objective of this study is to assess the level of association between prenatal household air pollution and child respiratory health, and to identify which HAP pollutants are associated with specific respiratory illnesses or symptoms and to what degree. Relevant studies were retrieved from PubMed databases up to April 27, 2010, and their reference lists were reviewed. Random effects models were applied to estimate summarized relative risks (RRs) and 95% confidence intervals (CIs). The analysis involved 11 studies comprising 387 767 mother-child pairs in total, assessing various respiratory health outcomes in children exposed to maternal prenatal HAP. Children with prenatal exposure to HAP pollutants exhibited a summary RR of 1.26 (95% CI=1.08-1.33) with moderate between-study heterogeneity (I²=49.22%) for developing respiratory illnesses. Specific associations were found between prenatal exposure to carbon monoxide (CO) (RR=1.11, 95% CI: 1.09-1.13), Nitrogen Oxides (NOx) (RR=1.46, 95% CI: 1.09-1.60), and particulate matter (PM) (RR=1.26, 95% CI: 1.2186-1.3152) and child respiratory illnesses (all had I² close to 0%, indicating no heterogeneity). Positive associations with child respiratory illnesses were also found with ultrafine particles (UFP), polycyclic aromatic hydrocarbons (PAH), and ozone (O3). However, no significant association was observed for prenatal exposure to sulfur dioxide (SO2). In summary, maternal prenatal exposure to HAP may contribute to a higher risk of child respiratory health issues, emphasizing the need for interventions to reduce this exposure during pregnancy. Targeted public health strategies such as improved ventilation, cleaner cooking technologies, and awareness campaigns should be implemented to minimize adverse respiratory effects on children.

Personal exposures to fine particulate matter and carbon monoxide in relation to cooking activities in rural Malawi

Background: Air pollution is a major environmental risk factor for cardiorespiratory disease. Exposures to household air pollution from cooking and other activities, are particularly high in Southern Africa. Following an extended period of participant observation in a village in Malawi, we aimed to assess individuals' exposures to fine particulate matter (PM 2.5) and carbon monoxide (CO) and to investigate the different sources of exposure, including different cooking methods. Methods: Adult residents of a village in Malawi wore personal PM 2.5 and CO monitors for 24-48 hours, sampling every 1 (CO) or 2 minutes (PM 2.5). Subsequent in-person interviews recorded potential exposure details over the time periods. We present means and interquartile ranges for overall exposures and summaries stratified by time and activity (exposure). We employed multivariate regression to further explore these characteristics, and Spearman rank correlation to examine the relationship between paired PM 2.5 and CO exposures. Results : Twenty participants (17 female; median age 40 years, IQR: 37-56) provided 831 hours of paired PM 2.5 and CO data. Concentrations of PM 2.5 during combustion activity, usually cooking, far exceeded background levels (no combustion activity): 97.9μg/m 3 (IQR: 22.9-482.0), vs 7.6μg/m 3, IQR: 2.5-20.6 respectively. Background PM 2.5 concentrations were higher during daytime hours (11.7μg/m 3 [IQR: 5.2-30.0] vs 3.3μg/m 3 at night [IQR: 0.7-8.2]). Highest exposures were influenced by cooking location but associated with charcoal use (for CO) and firewood on a three-stone fire (for PM 2.5). Cooking-related exposures were higher in more ventilated places, such as outside the household or on a walled veranda, than during indoor cooking. Conclusions : The study demonstrates the value of combining personal PM 2.5 exposure data with detailed contextual information for providing deeper insights into pollution sources and influences. The finding of similar/lower exposures during cooking in seemingly less-ventilated places should prompt a re-evaluation of proposed clean air interventions in these settings.

Personal air pollutant exposure monitoring in South African children in the VHEMBE birth cohort

The burden of disease associated with environmental exposures disproportionately impacts residents of low- and middle-income countries. Children living in rural regions of these countries may experience higher exposure to insecticides from indoor residual spraying used for malaria control and household air pollution. This study evaluated environmental exposures of children living in a rural region of South Africa. Quantifying exposure levels and identifying characteristics that are associated with exposure in this geographic region has been challenging due to limitations with available monitoring techniques. Wearable passive samplers have recently been shown to be a convenient and reliable tool for assessing personal exposures. In this study, a passive sampler wristband, known as Fresh Air wristband, was worn by 49 children (five-years of age) residing in the Limpopo province of South Africa. The study leveraged ongoing research within the Venda Health Examination of Mothers, Babies, and their Environment (VHEMBE) birth cohort. A wide range of chemicals (35 in total) were detected using the wristbands, including polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides, phthalates, and organophosphate esters (OPEs) flame retardants. Higher concentrations of PAHs were observed among children from households that fell below the food poverty threshold, did not have access to electric cookstoves/burners, or reported longer times of cooking or burning materials during the sampling period. Concentrations of p,p'-DDD and p,p'-DDT were also found to be elevated for children from households falling below the food poverty threshold as well as for children whose households were sprayed for malaria control within the previous 1.5 years. This study demonstrates the feasibility of using passive sampler wristbands as a non-invasive method for personal exposure assessment of children in rural regions of South Africa to complex mixtures environmental contaminants derived from a combination of sources. Future studies are needed to further identify and understand the effects of airborne environmental contaminants on childhood development and strategies to mitigate exposures.

The Effect of Kitchen Ventilation Modification on Independent and Combined Associations of Cooking Fuel Type and Cooking Duration with Suicidal Ideation: A Cross-Sectional Study

Although household air pollution (HAP) is associated with an increased risk of mental disorders, evidence remains scarce for the relationship between HAP and suicidal ideation. A total of 21,381 qualified participants were enrolled on the Henan Rural Cohort Study. HAP information including cooking fuel type, cooking duration and kitchen ventilation was collected by questionnaires. Suicidal ideation was evaluated by item nine of the Patient Health Questionnaire-9 (PHQ-9). Independent and combined associations of cooking fuel type and cooking duration with suicidal ideation were explored by logistic regression models. Analyses were conducted in different kitchen ventilation groups to detect the potential effect modification. The adjusted odds ratio (OR) and 95% confidence interval (95% CI) of solid fuel users versus clean fuel users for suicidal ideation was 1.37 (1.16, 1.62), and the risk of suicidal ideation increased by 15% (95% CI: 5%, 26%) for each additional hour of the cooking duration. Participants cooking with solid fuel for long durations were related to the highest risk of suicidal ideation (OR (95% CI): 1.51 (1.22, 1.87)). However, all these associations were not observed in those cooking with mechanical ventilation. Mechanical ventilation ameliorated relationships between solid fuel use and long-duration cooking with suicidal ideation.

Physical activity attenuates the association between household air pollution and health-related quality of life in Chinese rural population: the Henan Rural Cohort Study

BACKGROUND AND PURPOSE

Limited research focused on the association between household air pollution (HAP) and health-related quality of life (HRQoL). This study aimed to investigate the association of HAP with HRQoL and the effect modification of physical activity.

METHOD

A total of 16,761 eligible participants were derived from the Henan Rural Cohort Study. Based on structured questionnaires, HAP was assessed by fuel type, cooking duration and kitchen ventilation; HRQoL was measured with utility index and VAS score from the European Quality of Life Five Dimension Five Level Scale (EQ-5D-5L); physical activity was assessed by the International Physical Activity Questionnaire. Generalized linear models and tobit regression models were utilized to explore the relationship of HAP with HRQoL. Further sensitivity analyses were conducted using structural equation models.

RESULTS

Compared with those who cooked with clean fuels, short-duration, or good kitchen ventilation, participants who cooked with solid fuels, long-duration, and poor ventilation had lower utility index and VAS score (All P < 0.001). The decrease in utility index for solid fuel users vs. clean fuel users were 0.06 [95%confidence interval (CI) 003, 0.08], 0.03 (95%CI 0.01, 0.04) and 0.02 (95%CI 0.01, 0.04) in low, moderate and high physical activity group, respectively, which decreased with physical activity levels (Pfor interaction < 0.05). Similar results were observed in associations of kitchen ventilation with utility index and VAS score.

CONCLUSION

HAP negatively associated with HRQoL in rural population, and potential intervention aimed at maintaining adequate physical activity.

TRAIL REGISTRATION

The Henan Rural Cohort Study has been registered at Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699). Date of registration: 06 July, 2015. http://www.chictr.org.cn/showproj.aspx?proj=11375 .

Personal exposures to fine particulate matter and carbon monoxide in relation to cooking activities in rural Malawi

Background: Air pollution is a major environmental risk factor for cardiorespiratory disease. Exposures to household air pollution from cooking and other activities, are particularly high in Southern Africa. Following an extended period of participant observation in a village in Malawi, we aimed to assess individuals' exposures to fine particulate matter (PM 2.5) and carbon monoxide (CO) and to investigate the different sources of exposure, including different cooking methods. Methods: Adult residents of a village in Malawi wore personal PM 2.5 and CO monitors for 24-48 hours, sampling every 1 (CO) or 2 minutes (PM 2.5). Subsequent in-person interviews recorded potential exposure details over the time periods. We present means and interquartile ranges for overall exposures and summaries stratified by time and activity (exposure). We employed multivariate regression to further explore these characteristics, and Spearman rank correlation to examine the relationship between paired PM 2.5 and CO exposures. Results : Twenty participants (17 female; median age 40 years, IQR: 37-56) provided 831 hours of paired PM 2.5 and CO data. Concentrations of PM 2.5 during combustion activity, usually cooking, far exceeded background levels (no combustion activity): 97.9μg/m 3 (IQR: 22.9-482.0), vs 7.6μg/m 3, IQR: 2.5-20.6 respectively. Background PM 2.5 concentrations were higher during daytime hours (11.7μg/m 3 [IQR: 5.2-30.0] vs 3.3μg/m 3 at night [IQR: 0.7-8.2]). Highest exposures were influenced by cooking location but associated with charcoal use (for CO) and firewood on a three-stone fire (for PM 2.5). Cooking-related exposures were higher in more ventilated places, such as outside the household or on a walled veranda, than during indoor cooking. Conclusions : The study demonstrates the value of combining personal PM 2.5 exposure data with detailed contextual information for providing deeper insights into pollution sources and influences. The finding of similar/lower exposures during cooking in seemingly less-ventilated places should prompt a re-evaluation of proposed clean air interventions in these settings.

Kitchen ventilation alleviated adverse associations of domestic fuel use and long-duration cooking with platelet indices as biomarkers of cardiovascular diseases

BACKGROUND

Abnormal platelet activity is considered as a potential mechanism of cardiovascular diseases (CVDs) related to household air pollution (HAP). However, evidence remains lacking for the association of HAP with platelet activity in low-middle income countries.

METHODS

27,349 individuals were obtained from the Henan Rural Cohort Study. A questionnaire was used to collect data on cooking fuel types, cooking frequency and time as well as kitchen ventilation which indirectly reflected HAP. Platelet activity was indicated by platelet count (PLT), platelet distribution width (PDW), mean platelet volume (MPV), ratio of mean platelet volume to platelet count (MPVP), platelet-large cell ratio (P-LCR) and plateletcrit (PCT). Associations of HAP with platelet activity were assessed by generalized linear mixed models.

RESULTS

Compared with the ones without cooking, participants who cooking using solid fuel, clean fuel, short- and long-duration cooking were at a high risk for increased platelet size (PDW, MPV, MPVP and P-LCR) but decreased PLT and PCT; long-duration cooking participants with non-using exhaust hood/extractor by solid fuel use were associated with a 0.259 f. (95%CI: 0.100, 0.418 fL), 0.115 f. (95%CI: 0.050, 0.181 fL), 0.001 (95%CI: 0.000, 0.003) and 0.928% (95%CI: 0.425, 1.431%) increment in PDW, MPV, MPVP and P-LCR values and these associations were prominent in women relative than that in men.

CONCLUSION

Using exhaust hood/extractor attenuated the positive associations of solid fuel use and long-duration cooking with increased platelet size in all participants and these associations were prominent in women, indicating that improving kitchen ventilation may be an effective strategy to reduce platelet dysfunction related to HAP, especially for women.

Social inequality influences the impact of household air pollution on birth outcomes

BACKGROUND

Studies demonstrated associations between maternal exposure to household air pollution from cooking and increased risk of adverse birth outcomes in offspring; however, the modifying effect of socioeconomic status (SES) on this association has not been explored.

OBJECTIVES

In a cohort of pregnant women with 800 single live births between 2016 and 2017 in rural and semi urban areas of Bangladesh, we tested the hypotheses that kitchen location and cooking fuel type affect birth outcomes (birth weight, low birth weight [LBW] and small for gestational age [SGA]) and these associations vary by SES.

METHODS

Demographic characteristics including SES, kitchen location and fuel type were assessed in prenatal visits. Neonatal anthropometric measurements were recorded within 72 h of births. We performed multivariable linear and logistic regressions adjusting for potential confounders to test the study hypotheses.

RESULTS

For newborns from households with indoor kitchens, adjusted mean birth weight was 65.13 g (95% confidence interval [CI]: -118.37, -11.90) lower and the odds of LBW and SGA were 58% (odds ratio [OR]:1.58, 95% CI: 1.12, 2.24) and 41% (OR: 1.41, 95% CI: 1.05, 1.92) higher compared to those born in households with outdoor kitchens. We found SES significantly modified the associations between kitchen location and birth outcomes in households using biomass fuels. Newborns from low SES households with indoor kitchens had 89 g lower birth weight and a higher odds of being born with LBW (OR: 2.08, 95% CI 1.23, 3.58), and SGA (OR: 1.70, 95% CI 1.06, 2.76) than those born in high SES households using outdoor kitchens.

CONCLUSIONS

In areas with poor access or affordability to clean fuel such as in our study population, cooking in an outdoor kitchen can reduce the burden of LBW and SGA, particularly for low SES households. Promoting outdoor kitchens is a possible intervention strategy to mitigate adverse birth outcomes.