BACKGROUND:Early Child Development (ECD) encompasses physical, cognitive, social, and emotional changes during childhood. Air pollution exposure has been associated with ECD delays. The Household Air Pollution Intervention Network (HAPIN) randomized controlled trial evaluated the health effects of a liquefied petroleum gas cookstove and fuel intervention during pregnancy and infancy. Here we present the intervention effect and exposure-response relationship between fine particulate matter (PM2.5) and ECD. METHODS:The HAPIN trial enrolled 3195 pregnant women in rural Guatemala, Peru, India, and Rwanda. ECD was assessed at 12 months of infant age using the Caregiver Reported Early Development Instruments (CREDI). Personal 24-hr PM2.5 exposure was measured from baseline through 12 months. Linear regression analyses were conducted to evaluate intervention effects on overall and domain-specific CREDI scores and exposure-response relationships between prenatal and postnatal PM2.5 and infant development. RESULTS:Of 3061 live births, 2446 (79.9%) had valid CREDI assessments at 12 months. Despite substantial reductions in personal PM2.5 exposures, the intervention did not have a significant effect on the overall age-standardized ECD score (adjusted mean difference 0.033, 95% CI: -0.023 to 0.088) or on sub-domain age-standardized scores. Subgroup analyses revealed that the intervention improved CREDI scores among infants whose mothers received the intervention before 18 weeks of gestation, and among female infants. No clear associations were observed between PM2.5 exposure and CREDI scores at 12 months. DISCUSSION:While the LPG stove intervention did not affect ECD outcomes, variations in timing and sex-specific differences may play a role in shaping intervention effectiveness, similar to findings we previously reported for birth outcomes.

BACKGROUND:While extensive research has linked ambient air pollution to increased COVID-19 infection rates and severity, the role of household air pollution-a major public health exposure affecting nearly 3 billion people globally-remains understudied. Here, we evaluate associations between a clean cooking intervention, personal household air pollution exposure, and serologic evidence of prior SARS-CoV-2 infection using exploratory intention-to-treat and exposure-response analyses. METHODS:The Household Air Pollution Intervention Network (HAPIN) Trial randomized 3,200 households in Guatemala, India, Peru, and Rwanda to either continue using traditional solid fuel cookstoves or receive liquefied petroleum gas stoves with continuous fuel supply and behavioral messaging. The current ancillary study leveraged personal exposures to PM2.5 and carbon monoxide (CO) and dried blood spot (DBS) samples collected in the Guatemala, India, and Peru HAPIN sites to study the association between personal air pollution exposures and COVID-19; Rwanda was excluded due to low COVID-19 prevalence at the time of collection. SARS-CoV-2-specific antibodies were measured from DBS samples to define serology-based infection status and quantify immune response. Analyses included exploratory intention-to-treat and observational exposure-response analyses of associations between personal air pollution exposure and serology-based SARS-CoV-2 infection status and antibody levels. RESULTS:While the intervention effectively reduced household air pollution exposures, no significant differences in COVID-19 infection or antibody levels between intervention and control groups were found. However, exposure-response analyses were suggestive of potential inverse associations between PM2.5 exposure and antibody levels, diverging from most studies of ambient air pollution. CONCLUSIONS:These findings suggest that household air pollution may influence SARS-CoV-2 infection and immune response through mechanisms distinct from those described for ambient air pollution.

BACKGROUND:Few studies have investigated how different exposure windows - gestational, early postnatal, and current - of secondhand smoke (SHS) contribute to early childhood caries (ECC). Understanding these critical windows is essential for designing targeted interventions. We evaluated the association between SHS exposure and ECC among preschoolers. METHOD:This study was nested within the prospective birth cohort (HAPIN trial) conducted in southern India (2018-2020). Comprehensive data on exposure, lifestyle, and health were collected at multiple maternal and child time points. Between April and September 2023, dental caries and current exposure were assessed in children aged 3 - 5 years by a trained dentist using standardized, calibrated methods. SHS exposure was measured using questionnaires and urinary nicotine metabolites (cotinine, 3-hydroxycotinine). Negative binomial hurdle models were used to assess associations between SHS exposure and ECC prevalence. RESULTS:Among 712 participants (mean age: 4.01 ± 0.45 years; 53.4% boys), 478 children (67.2%) were diagnosed with ECC. Children exposed to SHS (urinary nicotine equivalents - sum of cotinine and 3-hydroxycotinine) during the gestational period demonstrated significantly higher prevalence of caries than their unexposed counterparts, with an incidence rate ratio (IRR) of 1.29 (95% CI, 1.18-1.42); second trimester was identified as a critical exposure window. Similarly, postnatal exposure increased ECC risk (IRR, 1.19; 95% CI, 1.08-1.31). Paternal smoking significantly elevated ECC prevalence, with children whose fathers smoked ≥11 cigarettes/day showing higher odds of ECC (odds ratio (OR), 1.90; 95% CI, 1.10-3.41). Urinary nicotine metabolites exhibited a dose-response relationship with ECC, showing the strongest association during pregnancy. Children classified as slow metabolizers were more vulnerable to third-trimester SHS exposure (OR, 1.74; 95% CI, 1.15-2.64). CONCLUSION:SHS exposure from pregnancy through early childhood was linked to higher odds of developing dental caries. CLINICAL SIGNIFICANCE:Findings underscore another precarious health risk associated with SHS exposure and highlight the need for integrated oral-environmental health prevention strategies.

Abstract Background Anaemia during pregnancy is a major public health concern in India. Biomass fuel use is common in a few rural areas of Tamil Nadu state and there is growing evidence that its use is associated with anaemia. The aim of this study was to estimate the prevalence of anaemia and to identify the coexisting determinants of anaemia among exclusive biomass-using rural pregnant women. Methods We conducted a cross-sectional analysis of baseline data collected from 799 rural pregnant women (gestational age between 9 and 20 weeks) from two districts of Tamil Nadu, India. All study participants used biomass for cooking and were enrolled in a multi-country randomised controlled trial of a liquefied petroleum gas cookstove intervention. Haemoglobin (Hb) was measured in capillary blood using the HemoCue®201 point of care device. Hb was categorized as normal (Hb ≥ 11 g/dL), mild anaemia (Hb 10.0–10.9 g/dL), moderate anaemia (Hb 7.0–9.9 g/dL), or severe anaemia (Hb < 7.0 g/dL). Multinomial and binary logistic regressions were used to identify factors associated with anaemia. Results Overall, prevalence of any anaemia was 66.7% (95% confidence interval: 63.4–70%) and that of mild anaemia was 31.9% (28.7–35.1%), moderate anaemia 33.7% (30.4–36.9%), and severe anaemia was 1.1% (0.6–2.2%). Body mass index classified as underweight (< 18.5 kg/m2), being a multigravida, and no observed hand washing facility in the household were associated with a significantly higher odds of anaemia. Conclusion This study population of exclusive biomass using pregnant women had higher rates of anaemia and underweight than that of rural estimates from recent NFHS reports for Tamil Nadu state, indicating the need to improve their overall anthropometric status and anaemia together, emphasizing the need for a transition to cleaner fuel.

Background & objectives Persistent mild inflammation is considered as a main contributor to the altered genesis of polycystic ovary syndrome (PCOS), with numerous studies reporting elevated serum levels of inflammatory markers. This inflammatory state may be attributed to genetic variants, particularly single nucleotide polymorphisms (SNP), that alter cytokine regulation. This study investigated the association of PCOS and inflammatory SNPs including interleukin (IL) such as IL-1β rs1143634, IL-1β rs16944, IL-6 rs1800795, IL-6 rs1800797, IL-6 rs1800796, IL-1RN; and tumour necrosis factor-alpha (TNF-α). Methods A total of 250 women volunteered for the study; of which 100 were diagnosed with PCOS and 150 were healthy controls. Serum levels of IL-6, IL-1β, and TNF-α were measured using enzyme-linked immunosorbent assay (ELISA). Genotyping was analysed using polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism (PCR-RFLP), or real-time PCR (RT-PCR). Genotype distributions amid groups were compared using the Chi-square test. Results Women with PCOS exhibited elevated serum levels of IL-1β than those of healthy controls which was considerably significant (P<0.001). The heterozygous genotypes of IL-1RN and IL-6 rs1800796 were seen more frequently in the control group (P=0.02), suggesting a potential inverse association. Interpretation & conclusions SNPs in IL-1 and IL-6 genes may influence susceptibility to PCOS and could confer a protective role in women of South Asian Indian origin.

Background:Household air pollution from biomass cookstoves is a major concern in low- and middle-income countries because it may be linked with increasing rates of metabolic disorders such as diabetes. We assessed cross-sectional associations between household air pollution concentrations and glycated hemoglobin (HbA1c) levels. Methods:We analyzed data from 346 women 40 to < 80 years of age who cooked with biomass fuel and were enrolled in the Household Air Pollution Intervention Network (HAPIN) Trial in Guatemala, India, Peru, and Rwanda. We explored associations of 24-h average personal exposure to fine particulate matter [PM ≤ 2.5 μ m in aerodynamic diameter ( PM 2.5 )], black carbon (BC), and carbon monoxide (CO) with HbA1c through individual pollutant linear models adjusted for potential confounders. We examined the effect modification of age, body mass index (BMI), and research site on the associations. Results:We did not observe evidence of associations between HbA1c (percentage points) and 1-unit increases in log-transformed PM 2.5 [ - 0.07 ; 95% confidence interval (CI): - 0.18 , 0.05], BC (0.01; 95% CI: - 0.15 , 0.13), or CO (0.07; 95% CI: - 0.24 , 0.10). Effect modification of the BC associations with HbA1c was observed for BMI and research site. An association in the hypothesized direction was observed among women with high BMI ( ≥ 25   kg / m 2 ): 0.13 (95% CI: - 0.06 , 0.31) compared with low BMI ( < 25   kg / m 2 ): - 0.17 (95% CI: - 0.38 , 0.04; p interaction = 0.04 ). In the Guatemala research site, there was an association in the hypothesized direction with HbA1c and log-transformed BC (0.36; 95% CI: 0.03, 0.70) that was countered by an association in the opposite direction as that hypothesized for the India site ( - 0.21 ; 95% CI: - 0.45 , 0.02) and associations consistent with the null association in the Peru and Rwanda sites ( p interaction = 0.05 ). No other evidence of effect modification was observed. Conclusions:Evidence suggests a need for further research to better understand household air pollution's influence on HbA1c, with particular attention on potential effect modifiers. https://doi.org/10.1289/JHP1053.

Epigenetic clocks are valuable tools for assessing biological age. Exposure to secondhand smoke (SHS) and polycyclic aromatic hydrocarbons (PAHs) has been linked with epigenetic age deviation (EAD) in adults. However, associations in children remain largely unexplored. We investigated relationships between exposure-spanning prenatal, early postnatal, current (36-60 months, time of sample collection) periods-and EAD in preschool-aged children. DNA methylation was measured in buccal cells from 43 children (mean age: 4.1 years) in the CAries Risk from exposure to Environmental tobacco Smoke-Household Air Pollution Intervention Network cohort. SHS exposure was assessed using urinary cotinine and 3-hydroxycotinine (3-HC), while PAHs exposure was assessed via urinary 2-naphthol (2-NAP) and 1-hydroxypyrene (1-PYR). Nicotine equivalents were calculated as molar sum of cotinine + 3-HC. EAD was estimated using Horvath, Skin&Blood, Pediatric Buccal Epigenetic (PedBE), and DNA methylation-based telomere length (DNAmTL) clocks. Associations between exposures and EAD were evaluated using linear regression, adjusting for study site, mother's education, child's body mass index z-score, age, and sex. Chronological age significantly correlated with all epigenetic clocks (r = 0.37-0.78) and with DNAmTL estimator (r = -0.38). Current SHS exposure, as measured by urinary cotinine, was associated with Horvath EAD (B = 0.23 years, P = .05). Similarly, current 3-HC and nicotine equivalents were positively associated with PedBE EAD (B = 0.08 years, P = .04; B = 0.11 years, P = .05, respectively). Among PAH metabolites, current 2-NAP levels were associated with principal component-based Skin&Blood EAD (B = 0.21 years, P = .02) and PedBE EAD (B = 0.13 years, P = .05). Findings suggest early-life SHS and PAHs exposure may contribute to accelerated epigenetic aging in children.

Background:Exposure to household air pollution from burning coal and biomass for cooking is associated with higher blood pressure and other adverse indicators of cardiovascular disease, the leading cause of death worldwide. Evidence demonstrating that switching from biomass to liquefied petroleum gas (LPG) will reduce blood pressure is limited. Methods:As part of a larger trial of 3200 households, we conducted a randomized trial of 342 women aged 40 to 79 years who lived in households using biomass for cooking in rural areas of Guatemala, India, Peru, and Rwanda to assess the effects of a free LPG stove and fuel intervention. Systolic blood pressure (one of four primary outcomes) was measured once prior to randomization and up to five times after randomization over 18 months. Results:A total of 418 participants were randomized (n=209 to intervention, and n=209 to control). Mean (standard deviation) systolic blood pressure at baseline was 112.7 (14.9) mmHg and 112.6 (14.7) mmHg in intervention and control participants, respectively. Adherence within the intervention arm was high. Among the 342 participants with a valid baseline and at least one valid post-randomization blood pressure measurement, mean (SD) post-randomization average systolic blood pressure was 111.5 (13.2) mmHg in the intervention arm and 111.9 (12.5) mmHg in the control arm, with an adjusted mean of difference of -0.56 mmHg (95% confidence interval, -2.19 to 1.07, p-value = 0.50). Conclusions:We did not observe evidence that an 18-month LPG stove and fuel intervention reduced blood pressure in women.

BACKGROUND:Exposure to polycyclic aromatic hydrocarbons (PAH), generated through incomplete combustion of organic materials such as coal and wood, and through activities, like charbroiling meat and smoking tobacco, negatively impact children's health. This study evaluates early-life PAH exposure in children from Southern India and its association with early childhood caries (ECC). METHODS:We utilized maternal and child urine samples from the Household Air Pollution Intervention Network (HAPIN) cohort to measure PAH metabolites: 2-naphthol (2-NAP) and 1-hydroxypyrene (1-PYR). We evaluated presence of dental caries in children (n = 712) using decayed, missing, and filled surfaces (dmfs) index. Socio-demographic data and dietary recall information were collected through questionnaires. Data analysis was conducted using a negative binomial hurdle model. FINDINGS:Dental caries prevalence was high, with 53.6 % of participants having cavitated lesions, 13.6 % showing non-cavitated lesions, and 32.8 % classified as caries-free. Elevated urinary concentrations of 2-NAP during first and third trimesters were associated with a 1.09-fold increase in caries incidence (95 % CI, 1.03-1.16 and 1.02-1.17, respectively). Postnatal exposure to 1-PYR at six months corresponded to an 8 % increase in ECC risk per log-unit rise (IRR, 1.08; 95 % CI, 1.02-1.16). Average postnatal PAH exposure (mean 96.55 μg/g creatinine) demonstrated a stronger link with each log-unit increase corresponding to an incident rate ratio (IRR) of 1.22 (95 % CI, 1.10-1.36) in the count model and an odds ratio (OR) of 1.36 (95 % CI, 1.06-1.63) in zero model. Categorical analyses revealed monotonic dose-response relationships, with children in the highest quartile of postnatal 2-NAP and 1-PYR exposure exhibiting 39 % and 35 % greater ECC burden, respectively, compared to those in the lowest quartile. INTERPRETATION:Our findings suggest an association between PAH exposure and ECC, particularly during the first and third trimesters with lifestyle factors playing a modifying role. The compounded impact of co-exposure to smoke from secondhand smoke and biomass-based cooking underscores critical need to reduce PAH exposure during early childhood.

BACKGROUND:Exposure to air pollutants, like fine particulate matter (PM2.5), has been linked to higher blood pressure (BP). Few studies have examined this association in biomass-dependent settings. We seek to determine whether high exposure during a 16 month period was associated with an increase in BP among older adult women over the study period and to determine whether short-term increases in exposure were associated with higher coincident blood pressure. METHODS:As part of a randomized controlled trial of a free liquefied petroleum gas cookstove and 18-month fuel supply, we measured BP and personal exposure to PM2.5, black carbon (BC), and carbon monoxide (CO) on 368 adult women (mean age 52) in four countries (Rwanda, Peru, Guatemala, and India). We considered short- and long-term associations, the latter measured by change in BP and the former in mixed models of repeated measures. FINDINGS:We found an association between short-term exposure and both systolic and diastolic BP. The highest quartile of BC was associated with a 2 mmHg increase compared to the referent group (p = 0.03). We also found a positive association with PM2.5, where the highest quartile had a 1.6 mmHg increase in SBP versus the referent group (p = 0.05). We found no association with long-term exposure, nor between CO and BP. INTERPRETATION:In settings where HAP dominates air pollution exposure, we found short-term exposure to BC and PM2.5 associated with increased BP, consistent with past literature. The lack of long-term associations may have been due to insufficient follow-up. FUNDING:The study is registered with ClinicalTrials.gov (NCT02944682) and funded by the U.S. National Institutes of Health (1UM1HL134590) in collaboration with the Bill & Melinda Gates Foundation (OPP1131279).

Introduction Prenatal and postnatal exposure to environmental tobacco smoke (ETS) has been linked with early childhood caries (ECC), but the specific molecular mechanisms and pathways remain largely unknown. The Caries Risk from exposure to Environmental tobacco Smoke (CARES) within the Household Air Pollution Intervention Network (HAPIN) study aims to establish the association between ETS and ECC by employing epidemiological and novel biomarker-based approaches. Here, we outline the overall design and rationale of the project.Methods and analysis We will leverage the infrastructure and data from the HAPIN trial (India) to mount the CARES study. In this ambidirectional cohort study, children (n=735, aged: 3–5 years) will undergo ECC examination by a trained dentist using standard criteria and calibrated methods. Structured questionnaires will be used to gather information on sociodemographic variables, dietary habits, oral hygiene, oral health-related quality of life and current exposure to ETS. We will collect non-invasive or minimally invasive biospecimens (i.e., saliva, buccal cells, dried blood spots and urine) from a subset of HAPIN children (n=120) to assess a battery of biomarkers indicative of exposure to ETS, early biological effect and epigenetic modifications. Both self-reported and objective measures of ETS exposure collected longitudinally during in utero and early postnatal periods will be accessed from the HAPIN database. We will apply current science data techniques to assess the association and interrelationships between ETS, ECC, and multiple biomarkers.Ethics and dissemination Information gathered in this research will be published in peer-reviewed journals and summaries will be shared with the key stakeholders as well as patients and their parents/guardians involved in this study. Sri Ramachandra Institute of Higher Education and Research Ethics Board has approved the study protocol (IEC-NI22/JUL/83/82).Trial registration number NCT02944682.

Background Household air pollution (HAP) from solid fuel use is associated with adverse birth outcomes, but data for exposure-response relationships are scarce. We examined associations between HAP exposures and birthweight in rural Guatemala, India, Peru, and Rwanda during the Household Air Pollution Intervention Network (HAPIN) trial. Methods The HAPIN trial recruited pregnant women (9-<20 weeks of gestation) in rural Guatemala, India, Peru, and Rwanda and randomly allocated them to receive a liquefied petroleum gas stove or not (ie, and continue to use biomass fuel). The primary outcomes were birthweight, length-for-age, severe pneumonia, and maternal systolic blood pressure. In this exposure-response subanalysis, we measured 24-h personal exposures to PM2 center dot 5, carbon monoxide, and black carbon once pre-intervention (baseline) and twice post-intervention (at 24-28 weeks and 32-36 weeks of gestation), as well as birthweight within 24 h of birth. We examined the relationship between the average prenatal exposure and birthweight or weight-for-gestational age Z scores using multivariate-regression models, controlling for the mother's age, nulliparity, diet diversity, food insecurity, BMI, the mother's education, neonate sex, haemoglobin, second-hand smoke, and geographical indicator for randomisation strata. Findings Between March, 2018, and February, 2020, 3200 pregnant women were recruited. An interquartile increase in the average prenatal exposure to PM 2 center dot 5 (74 center dot 5 mu g/m(3)) was associated with a reduction in birthweight and gestational age Z scores (birthweight: -14 center dot 8 g [95% CI -28 center dot 7 to -0 center dot 8]; gestational age Z scores: -0 center dot 03 [-0 center dot 06 to 0 center dot 00]), as was an interquartile increase in black carbon (7 center dot 3 mu g/m(3); -21 center dot 9 g [-37 center dot 7 to -6 center dot 1]; -0 center dot 05 [-0 center dot 08 to -0 center dot 01]). Carbon monoxide exposure was not associated with these outcomes (1 center dot 7; -3 center dot 1 [-12 center dot 1 to 5 center dot 8]; -0 center dot 003 [-0 center dot 023 to 0 center dot 017]). Interpretation Continuing efforts are needed to reduce HAP exposure alongside other drivers of low birthweight in low-income and middle-income countries. Copyright (c) 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.

Exposure to heat is associated with a substantial burden of disease and is an emerging issue in the context of climate change. Heat is of particular concern in India, which is one of the world's hottest countries and also most populous, where relatively little is known about personal heat exposure, particularly in rural areas. Here, we leverage data collected as part of a randomized controlled trial to describe personal temperature exposures of adult women (40-79 years of age) in rural Tamil Nadu. We also characterize measurement error in heat exposure assessment by comparing personal exposure measurements to the nearest ambient monitoring stations and to commonly used modeled temperature data products. We find that temperatures differ across individuals in the same area on the same day, sometimes by more than 5 °C within the same hour, and that some individuals experience sharp increases in heat exposure in the early morning or evening, potentially a result of cooking with solid fuels. We find somewhat stronger correlations between the personal exposure measurements and the modeled products than with ambient monitors. We did not find evidence of systematic biases, which indicates that adjusting for discrepancies between different exposure measurement methods is not straightforward.

Background Exposure to environmental tobacco smoke (ETS) is arguably the most ubiquitous and hazardous, even at very low levels, starting in early life. The objective of this study was to describe the state of research and future trends on ETS exposure and Children’s Health (CH) topics with bibliometrics and altmetrics. Methods An electronic search was performed in Scopus database on January 31, 2023. Consensus was arrived on 100 most-cited articles by two reviewers. These papers were then cross matched with citations harvested from Web of Science (WoS) and Google Scholar. Altmetric Attention Score (AAS) and Dimension counts were also collected. Analysis and network visualization of authors, countries, and keywords were generated using VOSviewer software. Results Among a total of 1107 articles published on ETS and CH, the 100 top-cited articles appeared in 54 journals, with Pediatrics (n = 12) contributing a maximum number of articles. The time period between 2000 and 2009 accounted for 44% of all publications. With respect to the research design employed across these studies, cross-sectional design took precedence over others accounting for approximately 40%. Predominantly, articles focused on childhood asthma; however, current research trends have shifted towards emerging fields such as children’s oral health and DNA methylation. Twitter, policy documents, and news outlets were the main platforms where outputs were discussed. The AAS was not associated with journal impact factor or access type. Weak correlations were observed between AAS and citation count in Scopus, WoS, and Google Scholar (r = 0.17 to 0.27) while a positive association existed between dimension count and the number of citations across all three databases (r = 0.84 to 0.98). Conclusion This study demonstrates the evolution, digital dissemination and research hotspots in the field of ETS and CH, predicting the possible future research directions. High-quality studies with more specific exposure classification are warranted to better understand the relationship between ETS and CH.