Prenatal, Early-Life, and Childhood Exposure to Air Pollution and Lung Function: The ALSPAC Cohort

The relationship between early life course air pollution exposure and general health in adolescence in the United Kingdom

Air pollution is associated with health in childhood. However, there is limited evidence on sensitive periods during the first 18 years of life. Data were drawn from the Millennium Cohort Study, a large and nationally representative cohort born in 2000/2002. Self-reported general health was assessed at age 17; number of hospital records were derived from linked health data (Hospital Episode Statistics) for consented participants. Residential history was linked to 25 × 25 m grid resolution annual PM2.5, PM10 and NO2 maps between 2000 and 2019; year-specific air pollution exposure in 200-m buffers around postcode centroids were computed. After adjusting for individual and time-variant area-level confounders, children exposed to higher air pollution in early (2-4 y) (n = 9137; PM2.5: OR = 1.06, 95% CI: 1.01-1.11; PM10: OR = 1.05, 95% CI: 1.01-1.09; NO2: OR = 1.01, 95% CI: 1.00-1.02) and middle childhood (5-7) (n = 9171; PM2.5: OR = 1.04, 95% CI: 1.00-1.07; PM10: OR = 1.03, 95% CI: 1.01-1.06) reported worse general health at age 17. Higher PM2.5 and NO2 exposure in adolescence increased the number of hospital episodes in young adulthood. Individuals from non-White and disadvantaged backgrounds were exposed to higher levels of air pollution. Air pollution in early and middle childhood might contribute to worse general health, with ethnic minority and disadvantaged children being more exposed.

Impacts of night market on indoor air quality and lung function of children in nearby households

BACKGROUND

Night markets-a unique element of Asian culture-involve various cooking methods and combustion, generating air pollutants with adverse health effects. However, there is no scientific literature on whether air pollutants from night markets affect indoor air quality and the lung function of children in nearby households.

OBJECTIVE

We evaluated the impacts of night market, specifically market opening days and household distance from the market, on indoor air quality and the lung function of children in nearby households.

METHODS

Using real-time monitoring equipment, we measured concentrations of particulate matter (PM)1, PM2.5, PM10, carbon dioxide (CO2), carbon monoxide (CO), nitrogen dioxide, sulfur dioxide (SO2), ozone, total volatile organic compound (TVOC), airborne bacteria, and fungi in 58 households located near a night market. Additionally, we assessed the lung function values of children living in these households.

RESULTS

PM1 and PM2.5 concentrations were significantly higher during opening days than during closing days. The lung function values for children were significantly lower in households located ≤595 m from the market (near group) than in those located >595 m from the market (far group). Higher CO2, CO, SO2, TVOCs, and PM10 concentrations and poor lung function were observed in children in the near group.

IMPACT STATEMENT

PM1 and PM2.5 concentrations were significantly higher during opening days of the night market than during closing days. Children residing near the night market (≤595 m) exhibited significantly lower lung function values than those living in houses located >595 m from the market.

How does air quality affect the health of children and adolescents?

OBJECTIVES

To assess how air quality and pollutants affect the health of children and adolescents.

SOURCE OF DATA

A narrative review of recent literature was conducted using PubMed databases, focusing on studies published between 2015 and 2023. The keywords included "air pollution", "child health", "adolescents", "respiratory diseases" and "cognitive development". The studies were selected based on their relevance to the pediatric community and impacts on air quality, emphasizing original peer-reviewed research and meta-analyses.

SYNTHESIS OF DATA

Exposure to pollutants in the air during the formative and development years can lead to respiratory disorders, neurodevelopmental impairment, and exacerbated chronic conditions. This review synthesizes current evidence on the relationship between air quality and pediatric health, emphasizing the effects of specific pollutants, mechanisms of harm, and long-term implications.

CONCLUSIONS

From respiratory disorders to neurodevelopmental problems, air pollution, remains a widespread threat, particularly to vulnerable populations. Immediate actions at the political, community, individual, and industry levels are necessary to mitigate these risks.

Kids' Environment and Health Cohort: Database Protocol: supplementary appendix

Introduction

Environmental exposures are known to affect the health and well-being of populations throughout the life course. Children are particularly susceptible to environmental impacts on educational and health outcomes as they spend more time in their local environments compared to adults. In England, no national, longitudinal dataset linking information about the physical and social environment in and around homes and schools to children's health and education outcomes currently exists. This limits our understanding of how environments might impact the health and well-being of children as they grow up.

Objective

To establish the Kids' Environment and Health Cohort, a research-ready, de-identified and annually updated national birth cohort of all children born in England from 2006 onwards.

Methods

The Kids' Environment and Health Cohort will link birth and mortality records, health and educational attainment datasets, to maternal health (up to 12 months prior to their child's birth), and environmental data for all children born in England from 2006 - approximately 11 million children at first build. A subset of children born between 2010 and 2012, and between 2020 and 2022 will be linked to their mothers' 2011 or 2021 Census records, respectively. The cohort database will be held in, and accessed via, a trusted research environment (TRE) at the Office for National Statistics (ONS). All geographical identifiers in the cohort, allowing for linkage to further environmental data, will be securely held by the ONS, separately to the main cohort, and will be encrypted before being shared with researchers.

Conclusion

The Kids' Environment and Health Cohort will, for the first time, link administrative health and education data to longitudinal environmental exposures for children at national level in England. It will serve as a data resource to support research about the health and well-being of children via improved home and school environments.

Life-course exposure to air pollution and the risk of dementia in the Lothian Birth Cohort 1936

Background

Air pollution in later life has been associated with dementia; however, limited research has investigated the association between air pollution across the life course, either at specific life periods or cumulatively. The project investigates the association of air pollution with dementia via a life-course epidemiological approach.

Methods

Participants of the Lothian Birth Cohort, born in 1936, provided lifetime residential history in 2014. Participant's air pollution exposure for time periods 1935, 1950, 1970, 1980, 1990, 2001, and 2007 was modeled using an atmospheric chemistry transport model. Lifetime cumulative exposures were calculated as time-weighted mean exposure. Of 572 participants, 67 developed all-cause dementia [35 with Alzheimer's dementia (AD)] by wave 5 (~82 years). Cox proportional hazards and competing risk models assessed the association between all-cause dementia and AD with particulate matter (diameter of ≤2.5 µm) PM2.5 and nitrogen dioxide (NO2) exposure at specific life periods and cumulatively. False discovery rate (FDR) correction was applied for multiple testing.

Results

The mean follow-up was 11.26 years. One standard deviation (SD) higher exposure to air pollution in 1935 (PM2.5 = 14.03 μg/m3, NO2 = 5.35 μg/m3) was positively linked but not statistically significant to all-cause dementia [PM2.5 hazard ratio (HR) = 1.16, 95% confidence interval (CI) = 0.90, 1.49; NO2 HR = 1.13, 95% CI = 0.88, 1.47] and AD (PM2.5 HR = 1.38, 95% CI = 1.00, 1.91; NO2 HR = 1.35, 95% CI = 0.92, 1.99). In the competing risk model, one SD elevated PM2.5 exposure (1.12 μg/m3) in 1990 was inversely associated with dementia (subdistribution HR = 0.82, 95% CI = 0.67, 0.99) at P = 0.034 but not after FDR correction (P FDR = 0.442). Higher cumulative PM2.5 per one SD was associated with an increased risk of all-cause dementia and AD for all accumulation models except for the early-life model.

Conclusion

The in-utero and early-life exposure to PM2.5 and NO2 was associated with higher AD and all-cause dementia risk, suggesting a sensitive/critical period. Cumulative exposure to PM2.5 across the life course was associated with higher dementia risk. Midlife PM2.5 exposure's negative association with all-cause dementia risk may stem from unaddressed confounders or bias.

Impact of environmental exposures on exhaled breath and lung function: NELA Birth Cohort

Introduction

Exposure to environmental factors (i.e. air pollution and second-hand tobacco smoke) have been associated with impaired lung function. However, the impact of environmental factors on lung health is usually evaluated separately and not with an exposomic framework. In this regard, breath analysis could be a noninvasive tool for biomonitoring of global human environmental exposure.

Methods

Data come from 337 mother-child pairs from the Nutrition in Early Childhood Asthma (NELA) birth cohort. Levels of BTEX (benzene, toluene, ethylbenzene and xylenes) in exhaled breath from mothers and children at 3 months after birth were estimated using gas chromatography-mass spectrometry. Short-term residential exposures (breath sampling day and 15 days before breath sampling) to nitrogen dioxide, particulate matter (PM2.5) and ozone were determined by chemical dispersion/transport modelling. Forced vital capacity, forced expiratory volume in 0.5 s (FEV0.5) and forced expiratory flow at 75% of FVC and at 25%-75% of FVC were measured in infants according to the raised-volume rapid thoracoabdominal compression technique.

Results

The results showed significant associations between short-term exposure to external agents and levels of benzene and toluene in exhaled breath. It was observed that exhaled levels of benzene and toluene were influenced by smoking status and outdoor air pollution in mothers, and by air pollution in infants (3 months of age). No significant relationship was observed between exposure to maternal tobacco smoking and/or short-term air pollution and lung function in healthy infants. However, there was a significant relationship between FEV0.5 and exhaled toluene in children.

Discussion

These findings indicated a significant relationship between environmental exposures and exhaled levels of benzene and toluene, suggesting that breath analysis could be a helpful exposure biomonitoring tool.

Approaches in landscape fire smoke pregnancy research and the impact on offspring: A review of knowledge gaps and recommendations

The increase in wildfires and bushfires due to climate change means that more people, including pregnant women and their fetuses will be exposed to landscape fire smoke. Although there is evidence to suggest that pregnancy landscape fire exposure is associated with lower birth weight, preterm birth and pregnancy loss, there is a lack of information on many other perinatal outcomes, as well as information on subsequent respiratory outcomes in children. Furthermore, due to the generally short term (hours/days) and intermittent nature of landscape fire smoke exposure, the knowledge to date has largely relied on natural experiments and ecological studies which can be subject to misclassification of exposure and a lack of precision. On the other hand, general urban outdoor air pollution exposure during pregnancy and subsequent perinatal and respiratory effects has been well studied. In particular, as air exposure modelling has improved so have the adaptations of methods to analyze the effects of air pollution exposure during pregnancy enabling critical windows of exposure to be identified. In this narrative review we summarize the current state of knowledge about the perinatal and respiratory effects of pregnancy landscape fire and particulate matter <2.5 μm in diameter (PM2.5) air pollution exposure, including a comment on analysis methods to date, and an assessment of how methodologies used in general air pollution research in relation to pregnancy exposure can be further harnessed for landscape fire smoke exposure pregnancy research.

Air pollution exposure during pregnancy and lung function in childhood: The LUIS study

BACKGROUND

The adverse effects of high air pollution levels on childhood lung function are well-known. Limited evidence exists on the effects of moderate exposure levels during early life on childhood lung function. We investigated the association of exposure to moderate air pollution during pregnancy, infancy, and preschool time with lung function at school age in a Swiss population-based study.

METHODS

Fine-scale spatiotemporal model estimates of particulate matter with a diameter <2.5 µm (PM2.5) and nitrogen dioxide (NO2) were linked with residential address histories. We compared air pollution exposures within different time windows (whole pregnancy, first, second, and third trimester of pregnancy, first year of life, preschool age) with forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) measured cross-sectionally using linear regression models adjusted for potential confounders.

RESULTS

We included 2182 children, ages 6-17 years. Prenatal air pollution exposure was associated with reduced lung function at school age. In children aged 12 years, per 10 µg·m-3 increase in PM2.5 during pregnancy, FEV1 was 55 mL lower (95% CI -84 to -25 mL) and FVC 62 mL lower (95% CI -96 to -28 mL). Associations were age-dependent since they were stronger in younger and weaker in older children. PM2.5 exposure after birth was not associated with reduced lung function. There was no association between NO2 exposure and lung function.

CONCLUSION

In utero lung development is most sensitive to air pollution exposure, since even modest PM2.5 exposure during the prenatal time was associated with reduced lung function, most prominent in younger children.

Pollution exposure in the first 3 months post transplant is associated with lower baseline FEV1 and higher CLAD risk

BACKGROUND

Exposure to air pollution post-lung transplant has been shown to decrease graft and patient survival. This study examines the impact of air pollution exposure in the first 3 months post-transplant on baseline (i.e., highest) forced expiratory volume in 1 second (FEV1) achieved and development of chronic lung allograft dysfunction (CLAD).

METHODS

Double-lung transplant recipients (n = 82) were prospectively enrolled for comprehensive indoor and personal environmental monitoring at 6- and 12-week post transplant and followed for >4 years. Associations between clinical and exposure variables were investigated using an exposomics approach followed by analysis with a Cox proportional hazards model. Multivariable analyses were used to examine the impact of air pollution on baseline % predicted FEV1 (defined as the average of the 2 highest values post transplant) and risk of CLAD.

RESULTS

Multivariable analysis revealed a significant inverse relationship between personal black carbon (BC) levels and baseline % FEV1. The multivariable model indicated that patients with higher-than-median exposure to BC (>350 ng/m3) attained a baseline % FEV1 that was 8.8% lower than those with lower-than-median BC exposure (p = 0.019). Cox proportional hazards model analysis revealed that patients with high personal BC exposure had a 2.4 times higher hazard risk for CLAD than patients with low BC exposure (p = 0.045).

CONCLUSIONS

Higher personal BC levels during the first 3 months post-transplant decrease baseline FEV1 and double the risk of CLAD. Strategies to reduce BC exposure early following a lung transplant may help improve lung function and long-term outcomes.

Windows of susceptibility and joint effects of prenatal and postnatal ambient air pollution and temperature exposure on asthma and wheeze in Mexican children

INTRODUCTION

Prenatal and early-life exposure to air pollution and extreme temperatures are associated with childhood asthma and wheeze. However, potential windows of susceptibility and their sex-specific and interactive effects have not been fully elucidated. We aimed to identify critical windows of susceptibility and evaluate sex-specific effects in these associations, and evaluate exposure interactions.

METHODS

We analyzed data from 468 mother-child pairs enrolled in the PROGRESS birth cohort in Mexico City. Daily residential levels of PM2.5, NO2, and temperature were generated from our validated spatiotemporally resolved models from conception to age 4 years. Childhood asthma and wheeze outcomes were collected at 4-6 and 7-8 years. Distributed lag nonlinear models (DLNMs) were used to identify susceptible windows for prenatal weekly-specific and postnatal monthly-specific associations of air pollution and temperature with respiratory outcomes adjusting for covariates. To evaluate sex-specific effects, DLNMs were stratified. Joint effects were assessed using relative excess risk due to interaction and attributable proportion.

RESULTS

Mid-gestation was a critical window for both PM2.5 (weeks 20-28, cumulative OR: 1.18 [95% CI: 1.01, 1.37]; weeks 19-26, cumulative OR: 1.18 [95% CI: 1.02, 1.36]) and NO2 (weeks 18-25, cumulative OR: 1.16 [95% CI: 1.02, 1.31]) exposure, associated with higher odds of wheeze. Postnatal exposure to PM2.5 and NO2 during the first year of life was also linked to higher odds of wheeze. The warmer and colder temperatures showed mixed effects on respiratory outcomes. We observed a synergistic interaction between high PM2.5 and high temperature exposure during the first year of life, associated with higher odds of current wheeze. The associations of prenatal air pollution and temperature exposure with respiratory outcomes were more pronounced in males.

CONCLUSIONS

Early-life air pollution exposure contributes to the development of childhood asthma and wheeze, while exposure to temperature showed mixed associations with respiratory outcomes.

Effect of environmental air pollutants on placental function and pregnancy outcomes: a molecular insight

Air pollution has become a major health concern, particularly for vulnerable populations such as the elderly, children, and pregnant women. Studies have reported a strong association between prenatal exposure to air pollutants and adverse pregnancy outcomes, including lower birth weight, reduced fetal growth, and an increased frequency of preterm births. This review summarizes the harmful effects of air pollutants, such as particulate matter, on pregnancy and outlines the mechanistic details associated with these adverse outcomes. Particulate pollutant matter may be able to cross the placenta barrier, and alterations in placental functions are central to the detrimental effects of these pollutants. In addition to associations with preeclampsia and gestational hypertension, air pollutants also induce oxidative stress, inflammation, and epigenetic alteration in the placenta. These pollutants can also affect placental homeostasis and endocrine function, contributing to pregnancy complications and possible transgenerational effects. Prenatal air pollution exposure has been linked to reduced cognitive and motor function in infants and newborns, increasing the predisposition to autism spectrum disorders and other neuropsychiatric disorders. This review also summarizes the use of various animal models to study the harmful effects of air pollution on pregnancy and postnatal outcomes. These findings provide valuable insight into the molecular events associated with the process and can aid in risk mitigation and adopting safety measures. Implementing effective environmental protocols and taking appropriate steps may reduce the global disease burden, particularly for developing nations with poor regulatory compliance and large populations of pregnant women.

Impact of ambient air pollution on lung function in preterm-born school-aged children

RATIONALE

Increased outdoor air pollution worsens lung function in children. However, these associations are less well studied in preterm-born individuals.

OBJECTIVES

We assessed associations between ambient air pollutants and spirometry measures in preterm-born children.

METHODS

The Respiratory Health Outcomes in Neonates study recruited preterm-born children aged 7-12 years who were born at ≤34 week's gestation. We associated four ambient air pollutants (particulate matter with aerodynamic diameter ≤2.5 µm (PM2.5), PM10, nitrogen dioxide (NO2) and sulfur dioxide) at time of birth and spirometry assessment and averaged exposure between these two time points with spirometry measures, using linear regression analyses. Gestational age was banded into 23-28, 29-31 and 32-34 week's. Regression models estimated spirometry values against pollutant levels at birth and at the time of spirometry.

MEASUREMENTS AND MAIN RESULTS

From 565 preterm-born children, 542 (96%) had satisfactory data. After adjustments for early and current life factors, significant detrimental associations were noted between PM10 at birth and per cent predicted forced vital capacity (%FVC) for the 23-28 and 29-31 week's gestation groups and between current PM2.5 and NO2 exposure and %FVC for the 23-28 week's gestation group. No associations with spirometry were noted for the averaged pollution exposure between birth and spirometry. Predictive models showed 5.9% and 7.4% differences in %FVC between the highest and lowest current pollution exposures for PM2.5 and NO2, respectively, in the 23-28 week group.

CONCLUSIONS

Birth and current exposures to road-traffic-associated pollutants detrimentally affected %FVC in preterm-born school-aged children, who already have compromised lung function.

A single-cell atlas of lung homeostasis reveals dynamic changes during development and aging

Aging is a global challenge, marked in the lungs by function decline and structural disorders, which affects the health of the elderly population. To explore anti-aging strategies, we develop a dynamic atlas covering 45 cell types in human lungs, spanning from embryonic development to aging. We aim to apply the discoveries of lung's development to address aging-related issues. We observe that both epithelial and immune cells undergo a process of acquisition and loss of essential function as they transition from development to aging. During aging, we identify cellular phenotypic alternations that result in reduced pulmonary compliance and compromised immune homeostasis. Furthermore, we find a distinctive expression pattern of the ferritin light chain (FTL) gene, which increases during development but decreases in various types of lung cells during the aging process.

Association of Fetal Lung Development Disorders with Adult Diseases: A Comprehensive Review

Fetal lung development is a crucial and complex process that lays the groundwork for postnatal respiratory health. However, disruptions in this delicate developmental journey can lead to fetal lung development disorders, impacting neonatal outcomes and potentially influencing health outcomes well into adulthood. Recent research has shed light on the intriguing association between fetal lung development disorders and the development of adult diseases. Understanding these links can provide valuable insights into the developmental origins of health and disease, paving the way for targeted preventive measures and clinical interventions. This review article aims to comprehensively explore the association of fetal lung development disorders with adult diseases. We delve into the stages of fetal lung development, examining key factors influencing fetal lung maturation. Subsequently, we investigate specific fetal lung development disorders, such as respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD), congenital diaphragmatic hernia (CDH), and other abnormalities. Furthermore, we explore the potential mechanisms underlying these associations, considering the role of epigenetic modifications, transgenerational effects, and intrauterine environmental factors. Additionally, we examine the epidemiological evidence and clinical findings linking fetal lung development disorders to adult respiratory diseases, including asthma, chronic obstructive pulmonary disease (COPD), and other respiratory ailments. This review provides valuable insights for healthcare professionals and researchers, guiding future investigations and shaping strategies for preventive interventions and long-term care.

Urban environment during pregnancy and lung function, wheezing, and asthma in school-age children. The generation R study

The urban environment during pregnancy may influence child's respiratory health, but scarce evidence exists on systematic evaluation of multiple urban exposures (e.g., air pollution, natural spaces, noise, built environment) on children's lung function, wheezing, and asthma development. We aimed to examine the association of the urban environment during pregnancy with lung function, preschool wheezing, and school-age asthma. We included 5624 mother-child pairs participating in a population-based prospective birth cohort. We estimated 30 urban environmental exposures including air pollution, road traffic noise, traffic, green spaces, blue spaces, and built environment during pregnancy. At 10 years of age, lung function was measured by spirometry. Information on preschool wheezing and physician-diagnosed school-age asthma was obtained from multiple questionnaires. We described single-exposure associations with respiratory outcomes using an exposome-wide association study. We also identified patterns of urban exposures with hierarchical clustering on principal components analysis and examined their associations with respiratory outcomes using multivariate regression models. Single-exposure analyses showed associations of higher particulate matter (PM) with lower mid-expiratory flow (FEF25-75%) (e.g., for PM < 2.5 μm of diameter [PM2.5] z-score = -0.06 [-0.09, -0.03]) and higher forced expiratory volume in 1s (FEV1) and forced vital capacity (FVC) (e.g., for PM2.5 FEV1 0.05 [0.02, 0.08]) after correction for multiple-hypothesis testing. Cluster analysis described three patterns of urban exposures during pregnancy and showed that the cluster characterised by higher levels of air pollution, noise, walkability, street connectivity, and lower levels of natural spaces were associated with lower FEF25-75% (-0.08 [-0.17, 0.00]), and higher odds of preschool wheezing (1.21 [1.03, 1.43]). This study shows that the characteristics of the urban environment during pregnancy are of relevance to the offspring's respiratory health during childhood.

Joint association of air pollution exposure and inflammation-related proteins in relation to infant lung function

BACKGROUND AND AIM

Systemic inflammation is one potential mechanism underlying negative impact of air pollution on lung function. Levels of inflammation-related proteins have the potential to characterize infants' susceptibility to air pollution induced lung function impairment. This study aimed to examine the interplay between air pollution exposure and inflammation-related proteins on lung function in 6-months-old infants.

METHODS

In the EMIL birth cohort from Stockholm (n = 82), dynamic spirometry, along with measurement of plasma levels of 92 systemic inflammation-related proteins (Olink Proseek Multiplex Inflammation panel) have been carried out in infants aged six months. Time-weighted average exposure to particles with an aerodynamic diameter of <10 μm (PM10), <2.5 μm (PM2.5), and nitrogen dioxide (NO2) at residential addresses from birth and onwards was estimated via validated dispersion models. To characterize the abnormality of inflammation-related protein profile, for each protein in each infant, we calculated the relative deviance of the protein level from age- and sex-specific median in terms of its age- and sex-specific interquartile range (IQR), followed by computing the absolute value of the smallest relative deviance, "minimum absolute deviance". Using linear regression models, interaction of air pollution and the abnormal inflammatory profile on lung function was estimated on the additive scale.

RESULTS

We found joint association of PM exposure and an abnormal inflammatory protein profile in relation to FEV0.5 and FVC. For 0.1 unit increase in minimum absolute deviance, one IQR increase in PM10 was associated with 85.9 ml (95% CI: -122.9, -48.9) additional decrease in FEV0.5, and 72.3 ml (95% CI: -121.5, -23.2) additional decrease in FVC. Similar results were obtained with PM2.5 exposure, while less apparent for NO2.

CONCLUSIONS

Early life air pollution exposure and abnormal inflammation-related protein profiles may interact synergistically towards lower lung function in infants.

Analysis of inequalities in personal exposure to PM2.5: A modelling study for the Greater London school-aged population

Exposure to air pollution can lead to negative health impacts, with children highly susceptible due to their immature immune and lung systems. Childhood exposure may vary by socio-economic status (SES) due to differences in both outdoor and indoor air pollution levels, the latter of which depends on, for example, building quality, overcrowding and occupant behaviours; however, exposure estimates typically rely on the outdoor component only. Quantifying population exposure across SES requires accounting for variations in time-activity patterns, outdoor air pollution concentrations, and concentrations in indoor microenvironments that account for pollution-generating occupant behaviours and building characteristics. Here, we present a model that estimates personal exposure to PM2.5 for ~1.3 million children aged 4-16 years old in the Greater London region from different income groups. The model combines 1) A national time-activity database, which gives the percentage of each group in different residential and non-residential microenvironments throughout a typical day; 2) Distributions of modelled outdoor PM2.5 concentrations; 3) Detailed estimates of domestic indoor concentrations for different housing and occupant typologies from the building physics model, EnergyPlus, and; 4) Non-domestic concentrations derived from a mass-balance approach. The results show differences in personal exposure across socio-economic groups for children, where the median daily exposure across all scenarios (winter/summer and weekends/weekdays) is 17.2 μg/m3 (95%CIs: 12.1 μg/m3-41.2 μg/m3) for children from households in the lowest income quintile versus 14.5 μg/m3 (95%CIs: 11.5 μg/m3 - 27.9 μg/m3) for those in the highest income quintile. Though those from lower-income homes generally fare worse, approximately 57 % of London's school-aged population across all income groups, equivalent to 761,976 children, have a median daily exposure which exceeds guideline 24-h limits set by the World Health Organisation. The findings suggest residential indoor sources of PM2.5 are a large contributor to personal exposure for school children in London. Interventions to reduce indoor exposure in the home (for example, via the maintenance of kitchen extract ventilation and transition to cleaner cooking fuels) should therefore be prioritised along with the continued mitigation of outdoor sources in Greater London.

Air pollution and pregnancy

Increased fossil fuel usage and extreme climate change events have led to global increases in greenhouse gases and particulate matter with 99% of the world's population now breathing polluted air that exceeds the World Health Organization's recommended limits. Pregnant women and neonates with exposure to high levels of air pollutants are at increased risk of adverse health outcomes such as maternal hypertensive disorders, postpartum depression, placental abruption, low birth weight, preterm birth, infant mortality, and adverse lung and respiratory effects. While the exact mechanism by which air pollution exerts adverse health effects is unknown, oxidative stress as well as epigenetic and immune mechanisms are thought to play roles. Comprehensive, global efforts are urgently required to tackle the health challenges posed by air pollution through policies and action for reducing air pollution as well as finding ways to protect the health of vulnerable populations in the face of increasing air pollution.

Low-dose bisphenols exposure sex-specifically induces neurodevelopmental toxicity in juvenile rats and the antagonism of EGCG

Bisphenols (BPs) can negatively affect neurobehaviors in rats, whereas the mechanism remains unclear. Here, the mechanism of BPs-induced neurodevelopmental toxicity and its effective detoxification measures were investigated in vitro and in vivo. In in vitro experiments, primary hippocampal neurons from neonatal rats of different genders were treated with bisphenol A (BPA), bisphenol S (BPS) and bisphenol B (BPB) at 1 nM-100 μM, epigallocatechin gallate (EGCG) and G15, an antagonist of G protein-coupled estrogen receptor (GPER) for 7 d. Results indicated that BPs affected neuronal morphogenesis, impaired GABA synthesis and Glu/GABA homeostasis. Neuronal morphogenetic damage induced by low-doses BPA may be mediated by GPER. Neurotoxicity of BPS is weaker than BPA and BPB. In in vivo studies, exposure to BPA (0.5 μg/kg·bw/day) on PND 10-40 caused oxidative stress and inflammation in rat hippocampus, disrupted neuronal morphogenesis and neurotransmitter homeostasis, ultimately impaired spatial memory of rats. Males are more sensitive to BPA exposure than females. Both in vivo and in vitro studies indicated that EGCG, a phytoestrogen, can alleviate BPA-induced neurotoxicity. Taken together, low-doses BPA exposure sex-specifically disrupted neurodevelopment and further impaired learning and memory ability in rats, which may be mediated by GPER. Promisingly, EGCG effectively mitigated the BPA-induced neurodevelopmental toxicity.

Air quality and respiratory health in children

Air pollution is a leading modifiable risk factor for various cardio-respiratory outcomes globally, both for children and for adults. Children are particularly susceptible to the adverse effects of air pollution due to various physiological and behavioural factors. Children are at a higher risk of outcomes such as acute respiratory infections, asthma and decreased lung function due to air pollution exposure; the risk varies in different geographical regions, depending on the source of air pollution, duration of exposures and concentration. Prenatal exposure to air pollution may also contribute to adverse respiratory outcomes later in life.

Prebirth effects of climate change on children's respiratory health

PURPOSE OF REVIEW

To date, there is no evidence that humanity will implement appropriate mitigation measures to avoid the catastrophic impact of climate change on the planet and human health. Vulnerable populations such as pregnant women and children will be the most affected. This review highlights epidemiologic data on climate change-related prenatal environmental exposures affecting the fetus and children's respiratory health.

RECENT FINDINGS

Research on outcomes of prenatal exposure to climate change-related environmental changes and pediatric pulmonary health is limited. In addition to adverse pregnancy outcomes known to affect lung development, changes in lung function, increased prevalence of wheezing, atopy, and respiratory infections have been associated with prenatal exposure to increased temperatures, air pollution, and maternal stress. The mechanisms behind these changes are ill-defined, although oxidative stress, impaired placental functioning, and epigenetic modifications have been observed. However, the long-term impact of these changes remains unknown.

SUMMARY

The detrimental impact of the climate crisis on pediatric respiratory health begins before birth, highlighting the inherent vulnerability of pregnant women and children. Research and advocacy, along with mitigation and adaptation measures, must be implemented to protect pregnant women and children, the most affected but the least responsible for the climate crisis.

Pre-natal exposure to NO2 and PM2.5 and newborn lung function: An approach based on repeated personal exposure measurements

CONTEXT

While strong evidence supports adverse effects of pre-natal air pollution on child's lung function, previous studies rarely considered fine particulate matter (PM_2.5) or the potential role of offspring sex and no study examined the effects of pre-natal PM_2.5 on the lung function of the newborn.

AIM

We examined overall and sex-specific associations of personal pre-natal exposure to PM_2.5 and nitrogen (NO₂) with newborn lung function measurements.

METHODS

This study relied on 391 mother-child pairs from the French SEPAGES cohort. PM_2.5 and NO₂ exposure was estimated by the average concentration of pollutants measured by sensors carried by the pregnant women during repeated periods of one week. Lung function was assessed with tidal breathing analysis (TBFVL) and nitrogen multiple breath washout (N₂MBW) test, performed at 7 weeks. Associations between pre-natal exposure to air pollutants and lung function indicators were estimated by linear regression models adjusted for potential confounders, and then stratified by sex.

RESULTS

Mean exposure to NO₂ and PM_2.5 during pregnancy was 20.2 μg/m³ and 14.3 μg/m³, respectively. A 10 μg/m³ increase in PM_2.5 maternal personal exposure during pregnancy was associated with an adjusted 2.5 ml (2.3%) decrease in the functional residual capacity of the newborn (p-value = 0.11). In females, functional residual capacity was decreased by 5.2 ml (5.0%) (p = 0.02) and tidal volume by 1.6 ml (p = 0.08) for each 10 μg/m³ increase in PM_2.5. No association was found between maternal NO₂ exposure and newborns lung function.

CONCLUSIONS

Personal pre-natal PM_2.5 exposure was associated with lower lung volumes in female newborns, but not in males. Our results provide evidence that pulmonary effects of air pollution exposure can be initiated in utero. These findings have long term implications for respiratory health and may provide insights into the underlying mechanisms of PM_2.5 effects.

Lung function and cognitive ability in children: a UK birth cohort study

BACKGROUND

Decreased adult lung function is associated with subsequent impairment in cognition. A similar relationship in early life could be of great policy importance, since childhood cognitive ability determines key adult outcomes, including socioeconomic status and mortality. We aimed to expand the very limited data available on this relationship in children, and hypothesised that reduced lung function would be longitudinally associated with decreased cognitive ability.

METHODS

Lung function was measured at age 8 (forced expiratory volume in one second (FEV₁), forced vital capacity (FVC); % predicted), and cognitive ability was measured at ages 8 (Wechsler Intelligence Scale for Children, third edition) and 15 (Wechsler Abbreviated Scale of Intelligence), in the Avon Longitudinal Study of Parents and Children. Potential confounders were identified as preterm birth, birth weight, breastfeeding duration, prenatal maternal smoking, childhood environmental tobacco smoke exposure, socioeconomic status and prenatal/childhood air pollution exposure. Univariable and multivariable linear models (n range=2332-6672) were fitted to assess the cross-sectional and longitudinal associations of lung function with cognitive ability, and change in cognitive ability between ages 8 and 15.

RESULTS

In univariate analyses, both FEV₁ and FVC at age 8 were associated with cognitive ability at both ages, but after adjustment, only FVC was associated with full-scale IQ (FSIQ) at ages 8 (β=0.09 (95% CI 0.05 to 0.12; p<0.001)) and 15 (β=0.06 (0.03 to 0.10; p=0.001)). We did not find evidence of an association between either lung function parameter and interval change in standardised FSIQ.

DISCUSSION

Reduced FVC, but not FEV₁, is independently associated with decreased cognitive ability in children. This low-magnitude association attenuates between ages 8 and 15, while no association is evident with longitudinal change in cognitive ability. Our results support a link between FVC and cognition across the life course, possibly due to shared genetic or environmental risk, rather than causation.

Associations between prenatal and early-life air pollution exposure and lung function in young children: Exploring influential windows of exposure on lung development

BACKGROUND

Evidence in the literature suggests that air pollution exposures experienced prenatally and early in life can be detrimental to normal lung development, however the specific timing of critical windows during development is not fully understood.

OBJECTIVES

We evaluated air pollution exposures during the prenatal and early-life period in association with lung function at ages 6-9, in an effort to identify potentially influential windows of exposure for lung development.

METHODS

Our study population consisted of 222 children aged 6-9 from the Fresno-Clovis metro area in California with spirometry data collected between May 2015 and May 2017. We used distributed-lag non-linear models to flexibly model the exposure-lag-response for monthly average exposure to fine particulate matter (PM2.5) and ozone (O3) during the prenatal months and first three years of life in association with forced vital capacity (FVC), and forced expiratory volume in the first second (FEV1), adjusted for covariates.

RESULTS

PM2.5 exposure during the prenatal period and the first 3-years of life was associated with lower FVC and FEV1 assessed at ages 6-9. Specifically, an increase from the 5th percentile of the observed monthly average exposure (7.55 μg/m3) to the median observed exposure (12.69 μg/m3) for the duration of the window was associated with 0.42 L lower FVC (95% confidence interval (CI): -0.82, -0.03) and 0.38 L lower FEV1 (95% CI: -0.75, -0.02). The shape of the lag-response indicated that the second half of pregnancy may be a particularly influential window of exposure. Associations for ozone were not as strong and typically CIs included the null.

CONCLUSIONS

Our findings indicate that prenatal and early-life exposures to PM2.5 are associated with decreased lung function later in childhood. Exposures during the latter months of pregnancy may be especially influential.

Outdoor Air Pollution and Childhood Respiratory Disease: The Role of Oxidative Stress

The leading mechanisms through which air pollutants exert their damaging effects are the promotion of oxidative stress, the induction of an inflammatory response, and the deregulation of the immune system by reducing its ability to limit infectious agents' spreading. This influence starts in the prenatal age and continues during childhood, the most susceptible period of life, due to a lower efficiency of oxidative damage detoxification, a higher metabolic and breathing rate, and enhanced oxygen consumption per unit of body mass. Air pollution is involved in acute disorders like asthma exacerbations and upper and lower respiratory infections, including bronchiolitis, tuberculosis, and pneumoniae. Pollutants can also contribute to the onset of chronic asthma, and they can lead to a deficit in lung function and growth, long-term respiratory damage, and eventually chronic respiratory illness. Air pollution abatement policies, applied in the last decades, are contributing to mitigating air quality issues, but more efforts should be encouraged to improve acute childhood respiratory disease with possible positive long-term effects on lung function. This narrative review aims to summarize the most recent studies on the links between air pollution and childhood respiratory illness.

Associations between early-life exposure to PM2.5 and reductions in childhood lung function in two North American longitudinal pregnancy cohort studies

Data integration of epidemiologic studies across different geographic regions can provide enhanced exposure contrast and statistical power to examine adverse respiratory effects of early-life exposure to particulate matter <2.5 microns in diameter (PM2.5). Methodological tools improve our ability to combine data while more fully accounting for study heterogeneity.

Methods

Analyses included children enrolled in two longitudinal birth cohorts in Boston, Massachusetts, and Mexico City. Propensity score matching using the 1:3 nearest neighbor with caliper method was used. Residential PM2.5 exposure was estimated from 2 months before birth to age 6 years using a validated satellite-based spatiotemporal model. Lung function was tested at ages 6-11 years and age, height, race, and sex adjusted z scores were estimated for FEV1, FVC, FEF25-75%, and FEV1/FVC. Using distributed lag nonlinear models, we examined associations between monthly averaged PM2.5 levels and lung function outcomes adjusted for covariates, in unmatched and matched pooled samples.

Results

In the matched pooled sample, PM2.5 exposure between postnatal months 35-44 and 35-52 was associated with lower FEV1 and FVC z scores, respectively. A 5 µg/m3 increase in PM2.5 was associated with a reduction in FEV1 z score of 0.13 (95% CI = -0.26, -0.01) and a reduction in FVC z score of 0.13 (95% CI = -0.25, -0.01). Additionally PM2.5 during postnatal months 23-39 was associated with a reduction in FEF25-75% z score of 0.31 (95% CI = -0.57, -0.05).

Conclusions

Methodological tools enhanced our ability to combine multisite data while accounting for study heterogeneity. Ambient PM2.5 exposure in early childhood was associated with lung function reductions in middle childhood.

Air pollution associated acute respiratory inflammation and modification by GSTM1 and GSTT1 gene polymorphisms: a panel study of healthy undergraduates

Epidemiological evidence has linked air pollution with adverse respiratory outcomes, but the mechanisms underlying susceptibility to air pollution remain unclear. This study aimed to investigate the role of glutathione S-transferase (GST) polymorphism in the association between air pollution and lung function levels. A total of 75 healthy young volunteers aged 18-20 years old were recruited for six follow-up visits and examinations. Spirometry was conducted to obtain lung function parameters such as forced vital capacity (FVC), and forced expiratory volume in 1 s (FEV₁). Nasal fluid concentrations of interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α), and 8-epi-prostaglandin F2α (8-epi-PGF2a) were measured using ELISA kits. Linear mixed-effect models were used to evaluate the association of air pollutants with respiratory outcomes. Additionally, polymorphisms of glutathione S-transferase mu 1 (GSTM1) and glutathione S-transferase theta 1 (GSTT1) were estimated to explore its role in the association between air pollutants and lung function. We found that short-term exposure to atmospheric particulates such as PM_2.5 and PM₁₀ can cause an increase in nasal biomarkers of inflammation, oxidative stress, and lung function, while air gaseous pollutant exposure is linked with decreased lung function, except for CO. Stratification analyses showed that an increase in nasal inflammatory cytokines caused by exposure to atmospheric particulates is more obvious in subjects with GSTM1-sufficient (GSTM1⁺) than GSTM1-null (GSTM1^-), while elevated lung function levels due to air particles are more significant in subjects with the genotype of GSTM1^- when compared to GSTM1⁺. As for air gaseous pollutants, decreased lung function levels caused by O₃, SO₂, and NO₂ exposure is more manifest in subjects with the genotype of GSTM1^- compared to GSTM1⁺. Taken together, short-term exposure to air pollutants is associated with alterations in nasal biomarkers and lung function levels in young healthy adults, and susceptible genotypes play an important mediation role in the association between exposure to air pollutants and inflammation, oxidative stress, and lung function levels.

Emission of Industrial Air Pollution and Mortality Due to Respiratory Diseases: A Birth Cohort Study in Poland

BACKGROUND

Air pollution is a major risk factor for public health worldwide, but evidence linking this environmental problem with the mortality of children in Central Europe is limited.

OBJECTIVE

To investigate the relationship between air pollution due to the emission of industry-related particulate matter and mortality due to respiratory diseases under one year of age.

METHODS

A retrospective birth cohort analysis of the dataset including 2,277,585 children from all Polish counties was conducted, and the dataset was matched with 248 deaths from respiratory diseases under one year of age. Time to death during the first 365 days of life was used as a dependent variable. Harmful emission was described as total particle pollution (TPP) from industries. The survival analysis was performed using the Cox proportional hazards model for the emission of TPP at the place of residence of the mother and child, adjusted individual characteristics, demographic factors, and socioeconomic status related to the contextual level.

RESULTS

Infants born in areas with extremely high emission of TPP had a significantly higher risk of mortality due to respiratory diseases: hazard ratio (HR) = 1.781 [95% confidence interval (CI): 1.175, 2.697], p = 0.006, compared with those born in areas with the lowest emission levels. This effect was persistent when significant factors were adjusted at individual and contextual levels (HR = 1.959 [95% CI: 1.058, 3.628], p = 0.032). The increased risk of mortality was marked between the 50th and 150th days of life, coinciding with the highest exposure to TPP.

CONCLUSIONS

The emission of TPP from industries is associated with mortality due to respiratory diseases under one year of age. A considerable proportion of children's deaths could be prevented in Poland, especially in urban areas, if air pollution due to the emission of particle pollution is reduced.

Prenatal Exposure to PM2.5 Oxidative Potential and Lung Function in Infants and Preschool- Age Children: A Prospective Study

BACKGROUND

Fine particulate matter (PM 2.5 ) has been found to be detrimental to respiratory health of children, but few studies have examined the effects of prenatal PM 2.5 oxidative potential (OP) on lung function in infants and preschool children.

OBJECTIVES

We estimated the associations of personal exposure to PM 2.5 and OP during pregnancy on offspring objective lung function parameters and compared the strengths of associations between both exposure metrics.

METHODS

We used data from 356 mother-child pairs from the SEPAGES cohort. PM filters collected twice during a week were analyzed for OP, using the dithiothreitol (DTT) and the ascorbic acid (AA) assays, quantifying the exposure of each pregnant woman. Lung function was assessed with tidal breathing analysis (TBFVL) and nitrogen multiple-breath washout (N 2 MBW ) test, performed at 6 wk, and airwave oscillometry (AOS) performed at 3 y. Associations of prenatal PM 2.5 mass and OP with lung function parameters were estimated using multiple linear regressions.

RESULTS

In neonates, an interquartile (IQR) increase in OP v DTT (0.89  nmol / min / m 3 ) was associated with a decrease in functional residual capacity (FRC) measured by N 2 MBW [β = - 2.26 mL ; 95% confidence interval (CI): - 4.68 , 0.15]. Associations with PM 2.5 showed similar patterns in comparison with OP v DTT but of smaller magnitude. Lung clearance index (LCI) and TBFVL parameters did not show any clear association with the exposures considered. At 3 y, increased frequency-dependent resistance of the lungs (Rrs 7 - 19 ) from AOS tended to be associated with higher OP v DTT (β = 0.09  hPa × s / L ; 95% CI: - 0.06 , 0.24) and OP v AA (IQR = 1.14  nmol / min / m 3 ; β = 0.12  hPa × s / L ; 95% CI: - 0.04 , 0.27) but not with PM 2.5 (IQR = 6.9   μ g / m 3 ; β = 0.02  hPa × s / L ; 95% CI: - 0.13 , 0.16). Results for FRC and Rrs 7 - 19 remained similar in OP models adjusted on PM 2.5 .

DISCUSSION

Prenatal exposure to OP v DTT was associated with several offspring lung function parameters over time, all related to lung volumes. https://doi.org/10.1289/EHP11155.

Impact of air pollution exposure on lung function and exhaled breath biomarkers in children and adolescents

A growing number of scientific papers focus on the description and quantification of the detrimental effects of pollution exposure on human health. The respiratory system is one of the main targets of these effects and children are potentially a vulnerable population. Many studies analyzed the effects of short- and long-term exposure to air pollutants on children's respiratory function. Aim of the present narrative review is to summarize the results of the available cohort studies which investigated how children's lung function is affected by exposure to air pollution. In addition, an overview is provided on the association, in children, between pollution exposure and exhaled breath biomarkers, as possible indicators of the pathogenetic mechanisms involved in pollution-related lung damages. The identified cohort studies suggest that, beside the possible impact of recent exposure, early and lifetime exposure are the variables most consistently associated with a reduction in lung function parameters in both children and adolescents. As for the effect of air pollution exposure on exhaled breath biomarkers, the available studies show an association with increased exhaled nitric oxide, with increased concentrations of malondialdehyde and 8-isoprostane in exhaled breath condensate (EBC), and with EBC acidification. These studies, therefore, suggest lung inflammation and oxidative stress as possible pathogenetic mechanisms involved in pollution related lung damages. Taken together, the available data underscore the importance of the development and application of policies aimed at reducing air pollutant concentration, since the protection of children's lung function can have a beneficial impact on adults' respiratory health in the future.

Health Outcomes in Children Associated with Prenatal and Early-Life Exposures to Air Pollution: A Narrative Review

(1) Background: The developmental origins of health and disease (DOHaD) hypothesis links adverse fetal exposures with developmental mal-adaptations and morbidity later in life. Short- and long-term exposures to air pollutants are known contributors to health outcomes; however, the potential for developmental health effects of air pollution exposures during gestation or early-childhood have yet to be reviewed and synthesized from a DOHaD lens. The objective of this study is to summarize the literature on cardiovascular and metabolic, respiratory, allergic, and neuropsychological health outcomes, from prenatal development through early childhood, associated with early-life exposures to outdoor air pollutants, including traffic-related and wildfire-generated air pollutants. (2) Methods: We conducted a search using PubMed and the references of articles previously known to the authors. We selected papers that investigated health outcomes during fetal or childhood development in association with early-life ambient or source-specific air pollution exposure. (3) Results: The current literature reports that prenatal and early-childhood exposures to ambient and traffic-related air pollutants are associated with a range of adverse outcomes in early life, including cardiovascular and metabolic, respiratory and allergic, and neurodevelopmental outcomes. Very few studies have investigated associations between wildfire-related air pollution exposure and health outcomes during prenatal, postnatal, or childhood development. (4) Conclusion: Evidence from January 2000 to January 2022 supports a role for prenatal and early-childhood air pollution exposures adversely affecting health outcomes during development. Future studies are needed to identify both detrimental air pollutants from the exposure mixture and critical exposure time periods, investigate emerging exposure sources such as wildfire, and develop feasible interventional tools.

Association of ambient and household air pollution with lung function in young adults in an peri-urban area of South-India: A cross-sectional study

OBJECTIVE

Although there is evidence for the association between air pollution and decreased lung function in children, evidence for adolescents and young adults is scarce. For a peri-urban area in India, we evaluated the association of ambient PM_2.5 and household air pollution with lung function for young adults who had recently attained their expected maximum lung function.

METHODS

We measured, using a standardized protocol, forced expiratory volume in the first second (FEV₁) and forced vital capacity (FVC) in participants aged 20-26 years from the third follow-up of the population-based APCAPCS cohort (2010-2012) in 28 Indian villages. We estimated annual average PM_2.5outdoors at residence using land-use regression. Biomass cooking fuel (a proxy for levels of household air pollution) was self-reported. We fitted a within-between linear-mixed model with random intercepts by village, adjusting for potential confounders.

RESULTS

We evaluated 1,044 participants with mean age of 22.8 (SD = 1) years (range 20-26 years); 327 participants (31%) were female. Only males reported use of tobacco smoking (9% of all participants, 13% of males). The mean ambient PM_2.5 exposure was 32.9 (SD = 2.8) µg/m³; 76% reported use of biomass as cooking fuel. The adjusted association between 1 µg/m³ increase in PM_2.5 was -27 ml (95% CI, -89 to 34) for FEV₁ and -5 ml (95% CI, -93 to 76) for FVC. The adjusted association between use of biomass was -112 ml (95% CI, -211 to -13) for FEV₁ and -142 ml (95% CI, -285 to 0) for FVC. The adjusted association was of greater magnitude for those with unvented stove (-158 ml, 95% CI, -279 to -36 for FEV₁ and -211 ml, 95% CI, -386 to -36 for FVC).

CONCLUSIONS

We observed negative associations between ambient PM_2.5 and household air pollution and lung function in young adults who had recently attained their maximum lung function.

Air pollution exposure impairs lung function in infants

Aim

To assess associations between air pollution exposure and infant lung function.

Methods

Healthy infants from Stockholm were recruited to two cohorts (n = 99 and n = 78). Infant spirometry included plethysmography and raised volume forced expiratory flows. In pooled analyses, lung function at ~6 months of age was related to time‐weighted average air pollution levels at residential addresses from birth until the lung function test. The pollutants included particulate matter with an aerodynamic diameter < 10 μm (PM₁₀) or <2.5 μm and nitrogen dioxide.

Results

There were significant inverse relations between air pollution exposure during infancy and forced expiratory volume at 0.5 s (FEV_0.5) as well as forced vital capacity (FVC) for all pollutants. For example, the decline was 10.1 ml (95% confidence interval 1.3–18.8) and 10.3 ml (0.5–20.1) in FEV_0.5 and FVC, respectively, for an interquartile increment of 5.3 μg/m³ in PM₁₀. Corresponding associations for minute ventilation and functional residual capacity were 43.3 ml/min (−9.75–96.3) and 0.84 ml (−4.14–5.82).

Conclusions

Air pollution exposure was associated with impaired infant lung function measures related to airway calibre and lung volume, suggesting that comparatively low levels of air pollution negatively affect lung function in early life.

Prenatal Exposure to Traffic-Related Air Pollution and the DNA Methylation in Cord Blood Cells: MOCEH Study

Particulate matter with a diameter of ≤10 µm (PM₁₀) and nitrogen dioxide (NO₂) affect the DNA methylation in the fetus, but epigenetic studies regarding prenatal exposure to air pollution in Asia are lacking. Therefore, this study aimed to assess whether there is any association between the ambient concentrations of PM₁₀ and NO₂ and CpG methylation in the cord blood DNA by using a Korean birth cohort. The concentrations of the air pollutants were incorporated into the final LUR model by using the maternal address data. The methylation level was determined using HumanMethylationEPIC BeadChip and a linear regression analysis model. A multipollutant model including both PM₁₀ and NO₂ and models with single pollutants were used for each trimester exposure. The number of differentially methylated positions was the largest for midpregnancy exposure in both the single pollutant models and the multipollutant regression analysis. Additionally, gene-set analysis regarding midpregnancy exposure revealed four gene ontology terms (cellular response to staurosporine, positive regulation of cytoskeleton organization, neurotransmitter transport, and execution phase of apoptosis). In conclusion, these findings show an association between prenatal PM₁₀ and NO₂ exposure and DNA methylation in several CpG sites in cord blood cells, especially for midpregnancy exposure.

Climate changes, air pollution and allergic diseases in childhood and adolescence

OBJECTIVE

To analyze the impacts of climate change on the development of immature respiratory and immune systems in children.

SOURCE OF DATA

The authors of the present study performed a non-systematic review of English, Spanish, and Portuguese articles published in the last five years in databases such as PubMed, EMBASE, and SciELO. The terms used were air pollution OR climate changes OR smoke, AND children OR health.

SYNTHESIS OF DATA

The increase in the prevalence of some diseases, such as allergic ones, is attributed to the interactions between genetic potential and the environment. However, disordered growth combined with inadequate waste management has caused problems for the planet, such as heatwaves, droughts, forest fires, increased storms and floods, interference in food crops and their nutritional values, changes in the infectious disease pattern, and air pollution resulting from the continuous use of fossil fuels. Children, beings still in the development stage with immature respiratory and immune systems, are the primary victims of the climate crisis.

CONCLUSIONS

The authors documented that prenatal and postnatal exposure to ambient air pollutants will accelerate or worsen the morbidity and mortality of many health conditions, including allergic diseases. Ambient air pollutants change the microbiota, interfere with the immune response, and take direct action on the skin and respiratory epithelium, which facilitates the penetration of allergens. Understanding how the children and adolescent health and well-being are affected by climate change is an urgent matter.

Associations between pre- and postnatal exposure to air pollution and lung health in children and assessment of CC16 as a potential mediator

BACKGROUND

Early life exposure to air pollution can affect lung health. Previous studies have not assessed the implications of both pre- and postnatal exposure to air pollutants on lung function at repeated ages during childhood. In addition, there is the need to identify potential mediators of such effect.

OBJECTIVES

To longitudinally assess the association between pre- and postnatal air pollution exposure and lung function during childhood. We also aimed to explore the role of Club cell secretory protein (CC16) as a potential mediator in this association.

METHODOLOGY

We included 487 mother-child pairs from the INMA (INfancia y Medio Ambiente) Sabadell birth cohort, recruited between 2004 and 2006. Air pollution exposure was estimated for pregnancy, pre-school age, and school-age using temporally adjusted land use regression (LUR) modelling. Lung function was measured at ages 4, 7, 9 and 11 by spirometry. At age 4, serum CC16 levels were determined in 287 children. Multivariable linear regression models and linear mixed modelling were applied, while considering potential confounders.

RESULTS

Prenatal exposure to Particulate Matter (PM)₁₀ and PM_coarse had the most consistent associations with reduced lung function in cross-sectional models. Associations with postnatal exposure were less consistent. Increasing CC16 levels at 4 years were associated with an increase in FEF_25-75 (β = 120.4 mL, 95% CI: 6.30, 234.5) from 4 to 11 years of age. No statistically significant associations were found between pre- or postnatal air pollution and CC16 at age 4.

CONCLUSION

Increasing levels of air pollution exposure, particularly prenatal PM₁₀ and PM_coarse exposure, were associated with a reduction in lung function. We were not able to confirm our hypothesis on the mediation role of CC16 in this association, however our results encourage further exploration of this possibility in future studies.

Cytokine profiles in cord blood in relation to prenatal traffic-related air pollution: The NELA cohort

BACKGROUND

Outdoor air pollution may disturb immune system development. We investigated whether gestational exposure to traffic-related air pollutants (TRAP) is associated with unstimulated cytokine profiles in newborns.

METHODS

Data come from 235 newborns of the NELA cohort. Innate response-related cytokines (IL-6, IFN-α, IL1-β, and TNF-α), Th1-related (IFN-γ and IL-2), Th2-related (IL-4, IL-5, and IL-13), Th17-related (IL-17 and IL-23), and immunomodulatory cytokine IL-10 were quantified in the supernatant of unstimulated whole umbilical cord blood cells after 7 days of culture using the Luminex technology. Dispersion/chemical transport modeling was used to estimate long-term (whole pregnancy and trimesters) and short-term (15 days before delivery) residential exposures to traffic-related nitrogen dioxide (NO₂ ), particulate matter (PM_2.5 and PM₁₀ ), and ozone (O₃ ). We fitted multivariable logistic regression, Bayesian kernel machine regression (BKMR), and weighted quantile sum (WQS) regression models.

RESULTS

NO₂ during the whole pregnancy increased the odds of detection of IL-1β (OR per 10 µg/m³ increase = 1.37; 95% CI, 1.02, 1.85) and IL-6 (OR per 10 µg/m³ increase = 1.32; 95% CI 1.00, 1.75). Increased odds of detected concentrations of IL-10 was found in newborns exposed during whole pregnancy to higher levels of NO₂ (OR per 10 µg/m³ increase = 1.30; 95% CI 0.99, 1.69), PM₁₀ (OR per 10 µg/m³ increase = 1.49; 95% CI 0.95, 2.33), and PM_2.5 (OR per 5 µg/m³ increase = 1.56; 95% CI 0.97, 2.51). Exposure to O₃ during the whole pregnancy increased the odds of detected IL-13 (OR per 10 µg/m³ increase = 1.22; 95% CI 1.01, 1.49). WQS model revealed first and third trimesters of gestation as windows of higher susceptibility.

CONCLUSIONS

Gestational exposure to TRAP may increase detection of pro-inflammatory, Th2-related, and T regulatory cytokines in newborns. These changes might influence immune system responses later in life.

Increased Impact of Air Pollution on Lung Function in Preterm versus Term Infants: The BILD Study

Rationale: Infants born prematurely have impaired capacity to deal with oxidative stress shortly after birth. Objectives: We hypothesize that the relative impact of exposure to air pollution on lung function is higher in preterm than in term infants. Methods: In the prospective BILD (Basel-Bern Infant Lung Development) birth cohort of 254 preterm and 517 term infants, we investigated associations of particulate matter ⩽10 μm in aerodynamic diameter (PM₁₀) and nitrogen dioxide with lung function at 44 weeks' postconceptional age and exhaled markers of inflammation and oxidative stress response (fractional exhaled nitric oxide [Fe_NO]) in an explorative hypothesis-driven study design. Multilevel mixed-effects models were used and adjusted for known confounders. Measurements and Main Results: Significant associations of PM₁₀ during the second trimester of pregnancy with lung function and Fe_NO were found in term and preterm infants. Importantly, we observed stronger positive associations in preterm infants (born 32-36 wk), with an increase of 184.9 (95% confidence interval [CI], 79.1-290.7) ml/min [Formula: see text]e per 10-μg/m³ increase in PM₁₀, than in term infants (75.3; 95% CI, 19.7-130.8 ml/min) (p_{prematurity × PM10 interaction} = 0.04, after multiple comparison adjustment p_adj = 0.09). Associations of PM₁₀ and Fe_NO differed between moderate to late preterm (3.4; 95% CI, -0.1 to 6.8 ppb) and term (-0.3; 95% CI, -1.5 to 0.9 ppb) infants, and the interaction with prematurity was significant (p_{prematurity × PM10 interaction} = 0.006, p_adj = 0.036). Conclusions: Preterm infants showed significantly higher susceptibility even to low to moderate prenatal air pollution exposure than term infants, leading to increased impairment of postnatal lung function. Fe_NO results further elucidate differences in inflammatory/oxidative stress response when comparing preterm infants with term infants.

Role of atmospheric particulate matter exposure in COVID-19 and other health risks in human: A review

Due to intense industrialization and urbanization, air pollution has become a serious global concern as a hazard to human health. Epidemiological studies found that exposure to atmospheric particulate matter (PM) causes severe health problems in human and significant damage to the physiological systems. In recent days, PM exposure could be related as a carrier for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus transmission and Coronavirus disease 2019 (COVID-19) infection. Hence, it is important to understand the adverse effects of PM in human health. This review aims to provide insights on the detrimental effects of PM in various human health problems including respiratory, circulatory, nervous, and immune system along with their possible toxicity mechanisms. Overall, this review highlights the potential relationship of PM with several life-limiting human diseases and their significance for better management strategies.

Air pollution and lung function in children

In this narrative review, we summarize the literature and provide updates on recent studies of air pollution exposures and child lung function and lung function growth. We include exposures to outdoor air pollutants that are monitored and regulated through air quality standards, and air pollutants that are not routinely monitored or directly regulated, including wildfires, indoor biomass and coal burning, gas and wood stove use, and volatile organic compounds. Included is a more systematic review of the recent literature on long-term air pollution and child lung function because this is an indicator of future adult respiratory health and exposure assessment tools have improved dramatically in recent years. We present "summary observations" and "knowledge gaps." We end by discussing what is known about what can be done at the individual/household, local/regional, and national levels to overcome structural impediments, reduce air pollution exposures, and improve child lung function. We found a large literature on adverse air pollution effects on children's lung function level and growth; however, many questions remain. Important areas needing further research include whether early-life effects are fixed or reversible; and what are windows of increased susceptibility, long-term effects of repeated wildfire events, and effects of air quality interventions.

Air Pollution Relates to Airway Pathology in Wheezing Children

Rationale: Outdoor air pollution contributes to asthma development and exacerbations, yet its effects on airway pathology have not been defined in children.

Objectives: To explore the possible link between air pollution and airway pathology, we retrospectively examined the relationship between environmental pollutants and pathological changes in bronchial biopsy specimens from children undergoing a clinically indicated bronchoscopy.

Methods: Structural and inflammatory changes (basement membrane [BM] thickness, epithelial loss, eosinophils, neutrophils, macrophages, mast cells, and lymphocytes) were quantified in biopsy specimens by using immunohistochemistry. The association between exposure to particulate matter less than 10 μm in aerodynamic diameter (PM₁₀), SO₂ and NO₂ and biopsy findings was evaluated by using a generalized additive model with Gamma family to allow for overdispersion, adjusted for atmospheric pressure, temperature, humidity, and wheezing.

Results: Overall, 98 children were included (age 5.3 ± 2.9 yr; 53 with wheezing/45 without wheezing). BM thickness increased with prolonged exposure to PM₁₀ (rate ratio [RR], 1.29; 95% confidence interval [CI], 1.09–1.52), particularly in children with wheezing. Prolonged exposure to PM₁₀ was also associated with eosinophilic inflammation in children with wheezing (RR, 3.16; 95% CI, 1.35–7.39). Conversely, in children without wheezing, increased PM₁₀ exposure was associated with a reduction of eosinophilic inflammation (RR, 0.12; 95% CI, 0.02–0.6) and neutrophilic inflammation (RR, 0.36; 95% CI, 0.14–0.89). Moreover, NO₂ exposure was also linked to reductions in neutrophil infiltration (RR, 0.57; 95% CI, 0.34–0.93) and eosinophil infiltration (RR, 0.33; 95% CI, 0.14–0.77).

Conclusions: Different patterns of association were observed in children with wheezing and in children without wheezing. In children without wheezing, exposure to PM₁₀ and NO₂ was linked to reduced eosinophilic and neutrophilic inflammation. Conversely, in children with wheezing, prolonged exposure to PM₁₀ was associated with increased BM thickness and eosinophilic inflammation, suggesting that it might contribute to asthma development by promoting airway remodeling and inflammation.

The first 1000 days of life: traffic-related air pollution and development of wheezing and asthma in childhood. A systematic review of birth cohort studies

BACKGROUND

The first 1000 days of life -including pregnancy and the first 2 years after birth- represent a critical window for health interventions. This systematic review aimed to summarize the evidence on the relationship between traffic-related air pollutants exposure in the first 1000 days of life and the development of wheezing and asthma, with a particular focus on windows of exposure.

METHODS

Medline and Embase were searched from January 2000 to May 2020 to retrieve population-based birth-cohort studies, including registries, providing quantitative information on the association between exposure to traffic-related air pollutants during pregnancy or early life, and the risk of developing wheezing and asthma in childhood. Screening and selection of the articles were completed independently by three reviewers. The quality of studies was assessed using the Newcastle-Ottawa scale.

RESULTS

Out of 9681 records retrieved, 26 studies from 21 cohorts were included. The most common traffic-related air pollutant markers were particulate matter (PM) and nitric oxides (NOx). The variability in terms of pollutants, exposure assessment methods, and exposure levels chosen to present the results did not allow a meta-analysis. Exposure to PM and NOx in pregnancy (10 cohorts) was consistently associated with an increased risk of asthma development, while the association with wheezing development was unclear. The second trimester of pregnancy seemed to be particularly critical for asthma risk. As for exposure during early life (15 cohorts), most studies found a positive association between PM (7/10 studies) and NOx (11/13 studies) and the risk of asthma development, while the risk of wheezing development was controversial. The period of postnatal exposure, however, was less precisely defined and a partial overlap between the period of exposure measurement and that of outcome development was present in a consistent number of studies (14 out of 15) raising doubts on the associations found.

CONCLUSIONS

Traffic-related air pollution during pregnancy is associated with an increased risk of asthma development among children and adolescents. The relationship between exposure in the first two years of life and the development of wheezing and asthma needs to be confirmed in studies with more precise exposure assessment.

Long-term Air Pollution Exposure Under European Union Limits and Adolescents' Lung Function: Modifying Effect of Abnormal Weight in the GINIplus and LISA Birth Cohorts

BACKGROUND

Abnormal weights, eg, obesity, has shown a strong modifying effect on the association between air pollution exposure and lung function impairment in adults.

RESEARCH QUESTION

How might weight status modify the effects of long-term air pollution exposure on adolescents' lung function, particularly in areas with pollution levels much lower than the current European Union (EU) air quality standards?

STUDY DESIGN AND METHODS

In this observational study, we investigated 2,224 adolescents from the German Infant Study on the Influence of Nutrition Intervention Plus Environmental and Genetic Influences on Allergy Development and the Influence of Life Style Factors on the Development of the Immune System and Allergies in East and West Germany birth cohorts. Lung function was measured at age 15 years. Underweight, normal weight, and overweight or obese were defined using percentiles of BMI. Average concentrations of air pollution were modelled at residential addresses at four exposure windows between 0 and 15 years. Multivariate linear regression models were fitted by weight group on lung function with exposure at each window or cumulative exposure since birth.

RESULTS

The median air pollution concentrations were half to two-thirds of the EU standards. Significant associations were observed only for individuals who were underweight and overweight or obese. For example, per interquartile range increase in nitrogen dioxide at the 15-year exposure window, FEV₁ declined by -2.9% (95% CI, -5.2% to -0.5%) for the underweight group and -3.4% (95% CI, -5.4% to -1.2%) for the overweight or obese group. Similarly, longer exposure to moderate-level air pollution since birth was associated significantly with lung function impairment for groups with abnormal weight.

INTERPRETATION

Exposure to low to moderate levels of air pollution was associated with lung function impairment for adolescents with abnormal weight. Longer exposure aggravated the adverse effect. Whether a critical exposure window since birth exists warrants further exploration.

Air pollution during infancy and lung function development into adolescence: The GINIplus/LISA birth cohorts study

BACKGROUND

Limited evidence exists on how air pollution exposure during infancy, i.e. the first year of life, may affect lung function development into adolescence.

OBJECTIVES

To investigate the association between exposure to air pollution during the first-year of life and lung function development up to the age of 15 in Germany.

METHODS

We investigated 915 children from the GINIplus and LISA birth cohorts from Munich (n = 181) and Wesel (n = 734), who had at least two spirometric measurements at ages 6, 10 and 15. Z-scores of forced expiratory volume in one second (FEV₁) and forced vital capacity (FVC) were calculated. Annual average concentrations of nitrogen dioxide, particulate matter with diameters <2.5, <10 and 2.5-10 µm (PM_{2.5/10/coarse}), and PM_2.5 absorbance at home addresses during the first-year of life, were estimated by land-use regression models. Associations between infancy exposure and lung function changes were fitted using multivariable linear mixed models with adjustment for potential confounders.

RESULTS

For per interquartile range increase in air pollutants during the first-year life, FEV₁ z-scores declined annually by -0.012 (95% confidence interval (CI): -0.014, -0.009) for PM_2.5 to -0.023 (95%CI: -0.028, -0.018) for PM_coarse. The declines in FVC were lower than FEV₁ [-0.006 (95%CI: -0.008, -0.003) to -0.011 (95%CI: -0.019, -0.003)]. In Munich, the attenuations were only significant for FEV₁. Effect estimates of infancy exposure for certain air pollutants were higher for groups with asthma, older maternal age, and breastfeeding <12 weeks than their counterparts.

DISCUSSION

Infancy exposure to higher air pollution may reduce lung function development up to adolescence, with airway size more affected than lung volume restriction. The potential modifying effects of maternal age, asthmatic status of children and breastfeeding warrant further exploration.

In Utero Exposure to Particulate Air Pollution during Pregnancy: Impact on Birth Weight and Health through the Life Course

In high-income countries, and increasingly in lower- and middle-income countries, chronic non-communicable diseases (NCDs) have become the primary health burden. It is possible that in utero exposure to environmental pollutants such as particulate matter (PM) may have an impact on health later in life, including the development of NCDs. Due to a lack of data on foetal growth, birth weight is often used in epidemiologic studies as a proxy to assess impacts on foetal development and adverse birth outcomes since it is commonly recorded at birth. There are no research studies with humans that directly link PM exposure in utero to birth weight (BW) and subsequently, the effects of lower BW on health outcomes in old age. It is, however, plausible that such associations exist, and it is thus important to assess the potential public health impacts of PM across the life course, and it is plausible to use birth weight as an indicator of risk. We therefore split this narrative review into two parts. In the first part, we evaluated the strength of the evidence on the impact of PM exposure during the entire pregnancy on birth weight outcomes in ten meta-analyses. In the second part, we reviewed the literature linking lower birth weight to childhood and adult chronic cardiovascular disease to explore the potential implications of PM exposure in utero on health later in life. Within the reviewed meta-studies on birth weight, there is sufficient evidence that PM pollution is associated with lower birth weight, i.e., the majority of meta-studies found statistically significant reductions in birth weight. From the second part of the review, it is evident that there is good evidence of associations between lower birth weight and subsequent cardiovascular disease risk. It is thus plausible that in utero exposure to PM is associated with lower birth weight and persisting biological changes that could be associated with adverse health effects in adulthood. Based on the reviewed evidence, however, the magnitude of later life cardiovascular health impacts from in utero exposure and its impact on BW are likely to be small compared to health effects from exposure to particulate air pollution over a whole lifetime.