Synergistic effects of air pollution and psychosocial stressors on adolescent lung function

D, Mandal S, Menon JS, Roy A, Dixit S, Gupta R, Swaminathan S, Thankachan P, Bhavnani S, Divan G, Prabhakaran P, van Schayck OCP, Babu GR, Srinivas PN, Mukherjee D. Protocol of the Nutritional, Psychosocial, and Environmental Determinants of Neurodevelopment and Child Mental Health (COINCIDE) study

Background

Over 250 million children are developing sub-optimally due to their exposure to early life adversities. While previous studies have examined the independent effects of nutritional status, psychosocial adversities, and environmental pollutants on children's outcomes, little is known about their interaction and cumulative effects.

Objectives

This study aims to investigate the independent, interaction, and cumulative effects of nutritional, psychosocial, and environmental factors on children's cognitive development and mental health in urban and rural India. It also seeks to explain pathways leading to inequities in child outcomes at the individual, household, and neighbourhood levels.

Methods

A mixed-methods prospective cohort study will be conducted on 1600 caregiver-child dyads (child age 3-10 years) in urban and rural India. Nutritional status, psychosocial adversities, environmental pollutants, and child mental health outcomes will be assessed using parent-report questionnaires. Performance-based measures will be used to assess cognitive outcomes. Venous blood and urine samples will be used to measure nutritional and pesticide biomarkers in 500 children. Indoor air pollution will be monitored in 200 households twice, during two seasons. Multilevel regression, weighted quantile sum regression, and Bayesian kernel machine regression will assess the individual and combined effects of exposures on child outcomes. Thematic analysis of in-depth interviews and focus group discussions will explore pathways to middle-and late childhood development inequities.

Discussion

The data will be used to formulate a Theory of Change (ToC) to explain the biological, psychosocial, and environmental origins of children's cognitive and mental health outcomes across the first decade of life in diverse Indian settings, which can inform interventions targets for promoting children's outcomes beyond the first 1000 days, potentially generalizable to similar under-resourced global settings. The COINCIDE research infrastructure will comprise a valuable global health resource, including prospective cohort data, validated study tools, and stored biological and environmental samples for future studies.

NPCC4: Climate change and New York City's health risk

This chapter of the New York City Panel on Climate Change 4 (NPCC4) report considers climate health risks, vulnerabilities, and resilience strategies in New York City's unique urban context. It updates evidence since the last health assessment in 2015 as part of NPCC2 and addresses climate health risks and vulnerabilities that have emerged as especially salient to NYC since 2015. Climate health risks from heat and flooding are emphasized. In addition, other climate-sensitive exposures harmful to human health are considered, including outdoor and indoor air pollution, including aeroallergens; insect vectors of human illness; waterborne infectious and chemical contaminants; and compounding of climate health risks with other public health emergencies, such as the COVID-19 pandemic. Evidence-informed strategies for reducing future climate risks to health are considered.

Fine Particulate Matter Metal Composition, Oxidative Potential, and Adverse Birth Outcomes in Los Angeles

BACKGROUND

Although many studies have linked prenatal exposure to PM 2.5 to adverse birth outcomes, little is known about the effects of exposure to specific constituents of PM 2.5 or mechanisms that contribute to these outcomes.

OBJECTIVES

Our objective was to investigate effects of oxidative potential and PM 2.5 metal components from non-exhaust traffic emissions, such as brake and tire wear, on the risk of preterm birth (PTB) and term low birth weight (TLBW).

METHODS

For a birth cohort of 285,614 singletons born in Los Angeles County, California, in the period 2017-2019, we estimated speciated PM 2.5 exposures modeled from land use regression with cokriging, including brake and tire wear related metals (barium and zinc), black carbon, and three markers of oxidative potential (OP), including modeled reactive oxygen species based on measured iron and copper (ROS), OH formation (OP OH ), and dithiothreitol (DTT) loss (OP DTT ). Using logistic regression, we estimated odds ratios (OR) and 95% confidence intervals (CI) for PTB and TLBW with speciated PM 2.5 exposures and PM 2.5 mass as continuous variables scaled by their interquartile range (IQR).

RESULTS

For both metals and oxidative potential metrics, we estimated increased risks for PTB (ORs ranging from 1.01 to 1.03) and TLBW (ORs ranging from 1.02 to 1.05) per IQR exposure increment that were robust to adjustment for PM 2.5 mass. Associations for PM 2.5 mass, black carbon, metal components, and oxidative potential (especially ROS and OP OH ) with adverse birth outcomes were stronger in Hispanic, Black, and mixed-race or Native American women.

DISCUSSION

Our results indicate that exposure to PM 2.5 metals from brake and tire wear and particle components that contribute to oxidative potential were associated with an increased risk of PTB and TLBW in Los Angeles County, particularly among Hispanic, Black, and mixed-race or Native American women. Thus, reduction of PM 2.5 mass only may not be sufficient to protect the most vulnerable pregnant women and children from adverse effects due to traffic source exposures. https://doi.org/10.1289/EHP12196.

Ozone Pollution, Perceived Support at Home, and Asthma Symptom Severity in the Adolescent Sample of the California Health Interview Survey

BACKGROUND

Outdoor air pollution, including ozone (O₃) pollution, and childhood family environments may interact and impact asthma exacerbations in children. Previous epidemiology studies have primarily focused on stress in the home, rather than support, and whether psychosocial factors modify the association between pollution and health outcomes, rather than whether pollution exposure modifies associations between psychosocial factors and health outcomes.

METHODS

Data from the cross-sectional 2003 representative, population-based California Health Interview Survey were linked with air quality monitoring data on O₃ pollution from the California Air Resources Board. Adolescents (N = 209) ages 12-17 who reported an asthma diagnosis and lived within 5 mi of the nearest air monitoring station had linked O₃ data for a 12-month period preceding the survey interview date. Adolescents reported perceived available support from an adult at home and frequency of asthma symptoms.

RESULTS

In unadjusted models, for adolescents living in high O₃ pollution regions, greater perceived support was related to lower asthma symptom frequency. Follow-up analyses suggested that the most plausible interpretation of the interaction was that O₃ exposure modified the association between perceived support and symptom frequency. O₃ × perceived support interactions were not statistically significant after adjusting for covariates.

CONCLUSIONS

These data provide preliminary evidence that the association between the lack of support in the home environment and worse asthma symptoms may be stronger in areas with higher O₃ exposure. Future work may benefit from incorporating personal pollution exposure assessments, comprehensive family environment assessments, and longitudinal follow-up of asthma exacerbations over time.

Ambient Air Pollution: Health Hazards to Children

Ambient air pollution is produced by sources including vehicular traffic, coal-fired power plants, hydraulic fracturing, agricultural production, and forest fires. It consists of primary pollutants generated by combustion and secondary pollutants formed in the atmosphere from precursor gases. Air pollution causes and exacerbates climate change, and climate change worsens health effects of air pollution. Infants and children are uniquely sensitive to air pollution, because their organs are developing and they have higher air per body weight intake. Health effects linked to air pollution include not only exacerbations of respiratory diseases but also reduced lung function development and increased asthma incidence. Additional outcomes of concern include preterm birth, low birth weight, neurodevelopmental disorders, IQ loss, pediatric cancers, and increased risks for adult chronic diseases. These effects are mediated by oxidative stress, chronic inflammation, endocrine disruption, and genetic and epigenetic mechanisms across the life span. Natural experiments demonstrate that with initiatives such as increased use of public transportation, both air quality and community health improve. Similarly, the Clean Air Act has improved air quality, although exposure inequities persist. Other effective strategies for reducing air pollution include ending reliance on coal, oil, and gas; regulating industrial emissions; reducing exposure with attention to proximity of residences, schools, and child care facilities to traffic; and a greater awareness of the Air Quality Index. This policy reviews both short- and long-term health consequences of ambient air pollution, especially in relation to developmental exposures. It examines individual, community, and legislative strategies to mitigate air pollution.

Air Pollution, Stress, and Allostatic Load: Linking Systemic and Central Nervous System Impacts

 Air pollution is a risk factor for cardiovascular and respiratory morbidity and mortality. A growing literature also links exposure to diverse air pollutants (e.g., nanoparticles, particulate matter, ozone, traffic-related air pollution) with brain health, including increased incidence of neurological and psychiatric disorders such as cognitive decline, dementia (including Alzheimer’s disease), anxiety, depression, and suicide. A critical gap in our understanding of adverse impacts of pollutants on the central nervous system (CNS) is the early initiating events triggered by pollutant inhalation that contribute to disease progression. Recent experimental evidence has shown that particulate matter and ozone, two common pollutants with differing characteristics and reactivity, can activate the hypothalamic-pituitary-adrenal (HPA) axis and release glucocorticoid stress hormones (cortisol in humans, corticosterone in rodents) as part of a neuroendocrine stress response. The brain is highly sensitive to stress: stress hormones affect cognition and mental health, and chronic stress can produce profound biochemical and structural changes in the brain. Chronic activation and/or dysfunction of the HPA axis also increases the burden on physiological stress response systems, conceptualized as allostatic load, and is a common pathway implicated in many diseases. The present paper provides an overview of how systemic stress-dependent biological responses common to particulate matter and ozone may provide insight into early CNS effects of pollutants, including links with oxidative, inflammatory, and metabolic processes. Evidence of pollutant effect modification by non-chemical stressors (e.g., socioeconomic position, psychosocial, noise), age (prenatal to elderly), and sex will also be reviewed in the context of susceptibility across the lifespan.

Susceptibility Variations in Air Pollution Health Effects: Incorporating Neuroendocrine Activation

Diverse host factors/phenotypes may exacerbate or diminish biological responses induced by air pollutant exposure. We lack an understanding of biological indicators of environmental exposures that culminate in a physiological response versus those that lead to adversity. Variations in response phenotype might arise centrally and/or at the local tissue level. In addition to genetic differences, the current evidence supports the roles of preexisting cardiopulmonary diseases, diabetes, diet, adverse prenatal environments, neurobehavioral disorders, childhood infections, microbiome, sex, and psychosocial stressors in modifying the susceptibility to air pollutant exposures. Animal models of human diseases, obesity, nutritional inadequacies, and neurobehavioral conditions have been compared with healthy controls to understand the causes of variations in susceptibility. Although psychosocial stressors have been associated with increased susceptibility to air pollutant effects, the contribution of neuroendocrine stress pathways in mediating these effects is just emerging. The new findings of neuroendocrine activation leading to systemic metabolic and immunological effects of air pollutants, and the potential contribution to allostatic load, emphasize the consideration of these mechanisms into susceptibility. Variations in susceptibility to air pollution health effects are likely to underlie host genetic and physiological conditions in concert with disrupted neuroendocrine circuitry that alters physiological stability under the influence of stressors.

Wearable Ultrafine Particle and Noise Monitoring Sensors Jointly Measure Personal Co-Exposures in a Pediatric Population

Epidemiological studies have linked both traffic-related air pollution (TRAP) and noise to adverse health outcomes, including increased blood pressure, myocardial infarction, and respiratory health. The high correlation between these environmental exposures and their measurement challenges have constrained research on how simultaneous exposure to TRAP and traffic noise interact and possibly enhance each other’s effect. The objective of this study was to deploy two novel personal sensors for measuring ultrafine particles (UFP, <100 nm diameter) and noise to concurrently monitor real-time exposures. Personal UFP monitors (PUFP, Enmont, LLC) were paired with NEATVIBEwear™ (Noise Exposure, Activity-Time and Vibration wearable), a personal noise monitoring device developed by the authors (Douglas Leaffer, Steve Doroff). A field-test of PUFP monitors co-deployed with NEATVIBEwear logged UFP, noise and ambient temperature exposure levels at 1-s resolution in an adolescent population in Cincinnati, OH to measure real-time exposures in microenvironments (transit, home, school). Preliminary results show that the concurrent measurement of noise exposures with UFP is feasible in a sample of physically active adolescent participants. Personal measurements of UFP and noise, measured prospectively in future studies, will enable researchers to investigate the independent and/or joint-effects of these health-relevant environmental exposures.

Using a Clustering Approach to Investigate Socio-Environmental Inequality in Preterm Birth-A Study Conducted at Fine Spatial Scale in Paris (France)

Background & Objectives: Today, to support public policies aiming to tackle environmental and health inequality, identification and monitoring of the spatial pattern of adverse birth outcomes are crucial. Spatial identification of the more vulnerable population to air pollution may orient health interventions. In this context, the objective of this study is to investigate the geographical distribution of the risk of preterm birth (PTB, gestational age ≤36 weeks) at the census block level in in city of Paris, France. We also aimed to assess the implication of neighborhood characteristics including air pollution and socio-economic deprivation. Material & Methods: Newborn health data are available from the first birth certificate registered by the Maternal and Child Care department of Paris. All PTB from January 2008 to December 2011 were geocoded at the mother residential census block. Each census block was assigned a socioeconomic deprivation level and annual average ambient concentrations of NO₂. A spatial clustering approach was used to investigate the spatial distribution of PTB. Results: Our results highlight that PTB is non-randomly spatially distributed, with a cluster of high risk in the northeastern area of Paris (RR = 1.15; p = 0.06). After adjustment for socio-economic deprivation and NO₂ concentrations, this cluster becomes not statistically significant or shifts suggesting that these characteristics explain the spatial distribution of PTB; further, their combination shows an interaction in comparison with SES or NO₂ levels alone. Conclusions: Our results may inform the decision makers about the areas where public health efforts should be strengthened to tackle the risk of PTB and to choose the most appropriate and specific community-oriented health interventions.

Chronic exposure to inhaled, traffic-related nitrogen dioxide and a blunted cortisol response in adolescents

BACKGROUND

Chronic health effects of traffic-related air pollution, like nitrogen dioxide (NO₂), are well-documented. Animal models suggested that NO₂ exposures dysregulate cortisol function.

OBJECTIVES

We evaluated the association between traffic-related NO₂ exposure and adolescent human cortisol concentrations, utilizing measures of the cortisol diurnal slope.

METHODS

140 adolescents provided repeated salivary cortisol samples throughout one day. We built a land use regression model to estimate chronic NO₂ exposures based on home and school addresses. We then generated model-based estimates of the association between cortisol and NO₂ exposure one year prior to cortisol sampling, examining changes in cortisol diurnal slope. The final model was adjusted other criteria pollutants, measures of psychosocial stress, anthropometry, and other demographic and covariates.

RESULTS

We observed a decrease in diurnal slope in cortisol for adolescents exposed to the estimated 75th percentile of ambient NO₂ (high exposure) relative to those exposed at the 25th percentile (low exposure). For a highly exposed adolescent, the log cortisol was lower by 0.06 µg/dl at waking (95% CI: -0.15, 0.02), 0.07 µg/dl at 30 min post waking (95% CI: -0.15, 0.02), and higher by 0.05 µg/dl at bedtime (95% CI: 0.05, 0.15), compared to a low exposed adolescent. For an additional interquartile range of exposure, the model-based predicted diurnal slope significantly decreased by 0.12 (95% CI: -0.23, -0.01).

CONCLUSIONS

In adolescents, we found that increased, chronic exposure to NO₂ and the mixture of pollutants from traffic sources was associated with a flattened diurnal slope of cortisol, a marker of an abnormal cortisol response which we hypothesize may be a mechanism through which air pollution may affect respiratory function and asthma in adolescents.

Advances in environmental and occupational disorders in 2016

In this review we highlight recent studies that advance the knowledge and understanding of the effects of various environmental factors and associated immune responses in patients with allergic diseases. This review will focus on new literature regarding allergic and immune responses to a variety of environmental factors, including aeroallergens, stinging insects, fungi, pollutants, viral respiratory tract infections, climate change, and microbial exposures.

Advances in asthma in 2016: Designing individualized approaches to management

In this year's Advances in Asthma review, we discuss viral infections in asthmatic patients and potential therapeutic agents, the microbiome, novel genetic associations with asthma, air quality and climate effects on asthma, exposures during development and long-term sequelae of childhood asthma, patient-centered outcomes research, and precision medicine. In addition, we discuss application of biomarkers to precision medicine and new information on asthma medications. New evidence indicates that rhinovirus-triggered asthma exacerbations become more severe as the degree of sensitization to dust mite and mouse increase. The 2 biggest drivers of asthma severity are an allergy pathway starting with allergic sensitization and an environmental tobacco smoke pathway. In addition, allergic sensitization and blood eosinophils can be used to select medications for management of early asthma in young children. These current findings, among others covered in this review, represent significant steps toward addressing rapidly advancing areas of knowledge that have implications for asthma management.