Urban Environmental Exposures Research Articles

3D built virtual arctic environment increase vigor through connectedness in older people.

While the life expectancy of older people has increased significantly, this is often related to more long-term care in healthcare residences and nursing homes. Staying in these facilities can lead to a reduction in the sense of connection with others and the world around, as well as in vigor, with significant psychophysical repercussions in the long term. Although previous studies have shown that the virtual nature can benefit both, there are no significant studies that have tested its effect in generating these positive outcomes in the older population. Therefore, our study sought to investigate, in a sample of 53 older people in care at a nursing home or healthcare residence, the indirect effect of a 3D built virtual arctic environment (vs. a 3D built virtual urban environment) exposure in virtual reality on vigor through connectedness. Both the virtual scenarios were designed with a first-person view, with no translation around the environment and only in-situ rotation. Results highlighted that exposure to the 3D built virtual arctic environment leads to higher connectedness than the 3D built virtual urban environment, and this, in turn, leads to an increase in vigor. Findings were discussed based on the potential of adopting virtual nature in facilities to improve older people's sense of connectedness and, in turn, improve their well-being.

Urban Environmental Exposures and Hypertensive Disease in the Helsinki Capital Region

Urban Environmental Exposures and Hypertensive Disease in the Helsinki Capital Region

Objective and subjective accounts of urban exposures for epidemiological research on mental health. Measurement and analysis

The interest in the impact of urban environmental exposures (UrbEEs) on mental health has greatly increased in the last two decades. Researchers have tended to measure said exposures either via...

Urban environment exposures, energy balance-related behaviors and their combination in preschoolers from three European countries

BackgroundUrban environments are characterized by many factors that may influence children’s energy balance-related behaviors (EBRBs), but there is limited research on the impact of prospective exposure to multiple urban factors in preschoolers. We evaluated prospective associations between various urban exposures and EBRBs in preschoolers across Europe, with EBRBs considered both individually and combined into lifestyle patterns. MethodsWe used data from 4,073 preschoolers (aged 3–4 years) participating in three European cohorts from the EU Child Cohort Network: BiB (United Kingdom), EDEN (France), and INMA (Spain). Eighteen built and food environment, green spaces, road traffic and ambient air pollution exposures were characterized at residential addresses. Various EBRBs were considered as the outcomes including screen time, sleep duration and diet (fruit, vegetables, discretionary sweet foods, sweet beverages) individually and combined into unhealthy lifestyle patterns, using principal components analysis. Associations between urban exposures and outcomes were estimated using a single-exposure analysis and the deletion-substitution-addition algorithm was used to construct multi-exposure models. ResultsIn multi-exposure models, greater walkability and smaller distance to the nearest road were associated with higher scores on the unhealthy lifestyle patterns. Likewise, greater walkability was associated with higher screen time and more frequent discretionary sweet food consumption. A smaller distance to the nearest road was also associated with lower sleep duration and more frequent sweet beverages consumption. On the other hand, higher levels of street connectivity showed an inverse association with the unhealthy lifestyle patterns. In the same vein, greater street connectivity was associated with decreased screen time. ConclusionThis comprehensive examination of multiple urban exposures indicates that residing in walkable environments and in close proximity to roads in densely-populated areas may not be advantageous for children EBRBs, while residing in neighborhoods with higher street connectivity appears to supposedly be beneficial.

Urban environment and health: a cross-sectional multiregional project based on population health surveys in Spain (DAS-EP project) – study protocol

IntroductionThe European Environment Agency estimates that 75% of the European population lives in cities. Despite the many advantages of city life, the risks and challenges to health arising from urbanisation...

The EMPOWER program: a history and guide for increasing diversity using integrated research and education.

The prevalence and pervasive nature of emerging chemicals of concern have created widespread environmental injustice apprehensions in vulnerable communities. To alleviate and address these concerns, identifying, engaging, and training a diverse environmental health research workforce will be critical and necessary steps to combat and prevent the consequences of environmental injustice. While there is an obvious need to enhance diversity in environmental health research, this process is hampered by facets of systemic racism that reduce access to educational resources needed to build interest and knowledge in students and teachers. We present here a historical perspective to offer a guide for building programs and relationships with underserved schools to help overcome limiting factors that have plagued certain public school systems. With the proper training and mentorship, the untapped workforce present within these schools will be empowered to understand and address current and emerging environmental health and safety threats. Through this transformative 8-week high school research program, we will develop well-prepared, ethical researchers committed to scientific inquiry, intensive fieldwork, and collaborative problem solving to address environmental health challenges. Following the four-step risk assessment process, students, teachers, and faculty mentors will work collaboratively to identify toxicants, potential hazards and risks, and environmental disparities in urban neighborhoods, which provides the necessary training to formulate critical thinking skills for use in academic or nonacademic careers.NEW & NOTEWORTHY The Engaging Multidisciplinary Professional Opportunities for Women in Environmental Research (EMPOWER) program is a one-of-a-kind research summer experience for minority female high school students in the state of Georgia. In addition, this program provides high school teachers with hands-on experiences that can be adapted to use in the classrooms. This combination of lab and field research immerses participants in understanding urban environmental exposures and their health effects. The EMPOWER program was established to meet the critical need for increasing diversity in science, technology, engineering, and mathematics.

Effects of green and urban environment exposure during classroom breaks in a video-based setting

AbstractNatural environments are beneficial for cognitive functioning and affect. Appraisals of such benefits can lead to the development of pro-environmental attitudes and behaviors in the long run. This study aimed to investigate the effects of an indirect exposure to a natural and urban environment during a short break in a school day, using a ‘green’ video depicting a walk through a lush forest and comparing it to an urban video portraying a walk through a busy city. We involved 91 fourth and fifth graders in a within-participants design. Results show that students decreased their performance in an arithmetic calculation task after watching the urban video, while no significant differences were observed before and after the exposure to the green environment. Students also reported experiencing more negative affect in relation to the exposure to the urban than the natural environment. Moreover, the students perceived the natural environment as more restorative than the urban environment. Taken together, our findings suggest that exposure to urban environments, in contrast to natural environments, may have negative effects on cognitive and affective functioning during school breaks. Educational implications suggest that when it is not possible to stay in a natural environment around the school, or there is no access to nature due to distance, videos of natural environments can be used during short breaks. They have potential to cognitively and affectively benefit students’ who may often be exposed to environmental stressors.

Urban environment in pregnancy and postpartum depression: An individual participant data meta-analysis of 12 European birth cohorts

BackgroundUrban environmental exposures associate with adult depression, but it is unclear whether they are associated to postpartum depression (PPD). ObjectivesWe investigated associations between urban environment exposures during pregnancy and PPD. MethodsWe included women with singleton deliveries to liveborn children from 12 European birth cohorts (N with minimum one exposure = 30,772, analysis N range 17,686–30,716 depending on exposure; representing 26–46 % of the 66,825 eligible women). We estimated maternal exposure during pregnancy to ambient air pollution with nitrogen dioxide (NO2) and particulate matter (PM2.5 and PM10), road traffic noise (Lden), natural spaces (Normalised Difference Vegetation Index; NDVI, proximity to major green or blue spaces) and built environment (population density, facility richness and walkability). Maternal PPD was assessed 3–18 months after birth using self-completed questionnaires. We used adjusted logistic regression models to estimate cohort-specific associations between each exposure and PPD and combined results via meta-analysis using DataSHIELD. ResultsOf the 30,772 women included, 3,078 (10 %) reported having PPD. Exposure to PM10 was associated with slightly increased odds of PPD (adjusted odd ratios (OR) of 1.08 [95 % Confidence Intervals (CI): 0.99, 1.17] per inter quartile range increment of PM10) whilst associations for exposure to NO2 and PM2.5 were close to null. Exposure to high levels of road traffic noise (≥65 dB vs. < 65 dB) was associated with an OR of 1.12 [CI: 0.95, 1.32]. Associations between green spaces and PPD were close to null; whilst proximity to major blue spaces was associated with increased risk of PPD (OR 1.12, 95 %CI: 1.00, 1.26). All associations between built environment and PPD were close to null. Multiple exposure models showed similar results. DiscussionThe study findings suggest that exposure to PM10, road traffic noise and blue spaces in pregnancy may increase PPD risk, however future studies should explore this causally.

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.

Prenatal Urban Environment and Blood Pressure Trajectories From Childhood to Early Adulthood

BackgroundPrenatal urban environmental exposures have been associated with blood pressure in children. The dynamic of these associations across childhood and later ages is unknown. ObjectivesThe purpose of this study was to assess associations of prenatal urban environmental exposures with blood pressure trajectories from childhood to early adulthood. MethodsRepeated measures of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were collected in up to 7,454 participants from a UK birth cohort. Prenatal urban exposures (n = 43) covered measures of noise, air pollution, built environment, natural spaces, traffic, meteorology, and food environment. An exposome-wide association study approach was used. Linear spline mixed-effects models were used to model associations of each exposure with trajectories of blood pressure. Replication was sought in 4 independent European cohorts (up to 9,261). ResultsIn discovery analyses, higher humidity was associated with a faster increase (mean yearly change in SBP for an interquartile range increase in humidity: 0.29 mm Hg/y, 95% CI: 0.20-0.39) and higher temperature with a slower increase (mean yearly change in SBP per interquartile range increase in temperature: −0.17 mm Hg/y, 95% CI: −0.28 to −0.07) in SBP in childhood. Higher levels of humidity and air pollution were associated with faster increase in DBP in childhood and slower increase in adolescence. There was little evidence of an association of other exposures with change in SBP or DBP. Results for humidity and temperature, but not for air pollution, were replicated in other cohorts. ConclusionsReplicated findings suggest that higher prenatal humidity and temperature could modulate blood pressure changes across childhood.

Toolkit for conducting citizen science activities in environmental epidemiology

Scientists and practitioners implementing citizen science projects, in which the involvement of citizens is key, often need ideas and tools that help in reaching citizens, engaging them in the project and maximizing their contributions. In this paper, we describe the creation of an open toolkit, a web-based portal citizensciencetoolkit.eu1 designed in the framework of the CitieS-Health project for the development and promotion of citizen science (CS) projects. The main focus is on projects linking urban environmental exposures and health, but it has applicability to other settings. The toolkit comprises the steps and phases during the implementation of CS activities in environmental epidemiology. A total of 28 tools are currently included, of which most were co-designed and tested within CitiesS-Health, as well as some resulting from external projects. For each tool, in addition to the details of its purpose and the specific challenges it poses, downloadable support content is available. To help facilitate inspiration and the adoption of tools provided, an illustrative step-by-step demonstration and description of its use in a CS project in a real-life setting is included, focusing on recommendations derived from the user experience. The portal is designed as a live inventory of tools, enabling interested CS practitioners not only to replicate, but also to continuously update and enrich it is content. To this end, the long-term objective of the portal is to act as a hub of resources that would enable the active inclusion of citizens in all the phases of the participatory research projects.

Policy relevant health related liveability indicator datasets for addresses in Australia’s 21 largest cities

Measuring and monitoring the spatial distribution of liveability is crucial to ensure that implemented urban and transport planning decisions support health and wellbeing. Spatial liveability indicators can be used to ensure these decisions are effective, equitable and tracked across time. The 2018 Australian National Liveability Study datasets comprise a suite of policy-relevant health-related spatial indicators of local neighbourhood liveability and amenity access estimated for residential address points and administrative areas across Australia’s 21 most populous cities. The indicators and measures encompass access to community and health services, social infrastructure, employment, food, housing, public open space, transportation, walkability and overall liveability. This national ’baseline’ liveability indicators dataset for residential address points and areas can be further linked with surveys containing geocoded participant locations, as well as Census data for areas from the Australian Statistical Geography Standard. The datasets will be of interest to planners, policy makers and researchers interested in modelling and mapping the spatial distribution of urban environmental exposures and their relationship with health and other outcomes.

Exposure to outdoor residential noise during pregnancy, embryonic size, fetal growth, and birth outcomes

IntroductionPrevious literature suggested that noise exposure during pregnancy was not associated with adverse birth outcomes. However, no studies evaluated the association between noise exposure and embryonic and fetal growth, or mutually assessed other urban environmental exposures such as traffic-related air pollution or natural spaces. MethodsWe included 7947 pregnant women from the Generation R Study, the Netherlands. We estimated total (road traffic, aircraft, railway, and industry), road traffic, and railway noise at the participants' home addresses during pregnancy using environmental noise maps. We estimated traffic-related air pollution using land-use regression models, greenness within a 300 m buffer using the normalized difference vegetation index, and distance to blue spaces using topographical maps at the home addresses. Embryonic size (crown-rump length) and fetal growth parameters (head circumference, femur length, and estimated fetal weight) were measured by ultrasound at several gestational ages. Information on neonatal anthropometrics at birth (head circumference, length, and weight) and adverse birth outcomes (preterm birth, low birth weight, and small for gestational age) were retrieved from medical records. ResultsHigher total noise exposure during pregnancy was associated with larger crown-rump length (0.07 SDS [95%CI 0.00 to 0.14]). No association was found with fetal growth parameters, neonatal anthropometrics, and adverse birth outcomes. Similar results were observed for road traffic noise exposure, while railway noise exposure was not associated with any of the outcomes. Traffic-related air pollution was not associated with crown-rump length. Total noise exposure mediated 15% of the association between exposure to greenness and smaller crown-rump length. No association was observed between distance to blue spaces and total noise exposure. ConclusionExposure to outdoor residential noise during pregnancy was associated with larger embryonic size. Moreover, a reduction of total noise exposure during pregnancy partially mediated the association between exposure to greenness and smaller embryonic size. Additional research is warranted to confirm and further understand these novel findings.

The impact of urban environmental exposures on health: An assessment of the attributable mortality burden in Sao Paulo city, Brazil

The impact of urban environmental exposures on health: An assessment of the attributable mortality burden in Sao Paulo city, Brazil

Using an Exposome-Wide Approach to Explore the Impact of Urban Environments on Blood Pressure among Adults in Beijing-Tianjin-Hebei and Surrounding Areas of China.

Existing studies mostly explored the association between urban environmental exposures and blood pressure (BP) in isolation, ignoring correlations across exposures. This study aimed to systematically evaluate the impact of a wide range of urban exposures on BP using an exposome-wide approach. A multicenter cross-sectional study was conducted in ten cities of China. For each enrolled participant, we estimated their urban exposures, including air pollution, built environment, surrounding natural space, and road traffic indicator. On the whole, this study comprised three statistical analysis steps, that is, single exposure analysis, multiple exposure analysis and a cluster analysis. We also used deletion-substitution-addition algorithm to conduct variable selection. After considering multiple exposures, for hypertension risk, most significant associations in single exposure model disappeared, with only neighborhood walkability remaining negatively statistically significant. Besides, it was observed that SBP (systolic BP) raised gradually with the increase in PM2.5, but such rising pattern slowed down when PM2.5 concentration reached a relatively high level. For surrounding natural spaces, significant protective associations between green and blue spaces with BP were found. This study also found that high population density and public transport accessibility have beneficially significant association with BP. Additionally, with the increase in the distance to the nearest major road, DBP (diastolic BP) decreased rapidly. When the distance was beyond around 200 m, however, there was no obvious change to DBP anymore. By cluster analysis, six clusters of urban exposures were identified. These findings reinforce the importance of improving urban design, which help promote healthy urban environments to optimize human BP health.

The impact of urban environmental exposures on health: An assessment of the attributable mortality burden in Sao Paulo city, Brazil

BackgroundCurrently, more than half of the global population lives in cities. Contemporary urban planning practices result in environmental risk factors (e.g. air pollution, noise, lack of green space, excess heat) that put health and well-being of city dwellers at risk and contribute to chronic diseases and premature death. Despite a growing body of evidence on adverse health impacts related to current urban and transport planning practices, especially for cities in the Global North, not much is known about associated health impacts in South American cities. Therefore, we estimated the mortality burden attributable to breaching internationally-recommended or locally-preferable exposure levels of urban planning related environmental exposures in Sao Paulo, Brazil. MethodsWe carried out a health impact assessment study, following the comparative risk assessment framework, to assess preventable mortality impacts of breaching exposure recommendations for air pollution, green spaces and temperature at the census tract (CT) level (n = 18,363). We also assessed the distribution thereof by socioeconomic vulnerability. ResultsWe estimated that annually 11,372 (95% CI: 7921; 15,910) attributable deaths could be prevented by complying with recommended exposure levels. The largest proportion of preventable mortality was due to breaching air pollution limits (i.e. 8409 attributable deaths), followed by insufficient green space (i.e. 2593), and excess heat (i.e. 370). Adverse health impacts were larger in CTs of lower socioeconomic vulnerability, due to demographic profile, traffic density and residential area configurations. DiscussionNot complying with the health limits for air pollution, green space and temperature exposures resulted in a considerable preventable mortality burden (i.e. 17% of total expected deaths) in Sao Paulo. This burden can be reduced by improving current urban and transport planning practices.

Urban grey spaces are associated with increased allergy in the general population

Backgroundthe built environment in urban areas may have side effects on children's respiratory health, whilst less is known for adulthood. Aimto assess the association between increasing exposure to grey spaces and allergic status in an adult general population sample. Methods2070 subjects (age range 15–84 yrs), living in Pisa/Cascina, Italy, were investigated in 1991–93 through a questionnaire on health status and risk factors, skin prick test (SPT), serum Immunoglobulins E (IgE), and serum antibodies to benzo(a)pyrene diol epoxide (BPDE)-DNA adducts.Land-cover exposure within a 1000 m buffer from each subject's home address was assessed through the CORINE Land Cover program (CLC 1990) within the FP7/HEALS project (2013–2018). Participants' residential addresses were geocoded and the proportion of surrounding grey spaces was calculated.Through logistic regression models, adjusting for potential confounding factors, the effect of a 10% increase in grey spaces exposure on allergic biomarkers/conditions was assessed; the relationship with serum antibodies to BPDE-DNA adducts positivity was also analyzed. ResultsA 10% increase in grey spaces coverage was associated with a higher probability of having SPT positivity (OR 1.07, 95% CI 1.02-1.13), seasonal SPT positivity (OR 1.12, 1.05-1.19), polysensitization (OR 1.11, 1.04-1.19), allergic rhinitis (OR 1.10, 1.04-1.17), co-presence of SPT positivity and asthma/allergic rhinitis (OR 1.16, 1.08-1.25), asthma/allergic rhinitis (OR 1.06, 1.00-1.12), presence of serum antibodies to BPDE-DNA adducts positivity (OR 1.07, 1.01-1.14). Conclusionsgrey spaces have adverse effects on allergic status and are related to a biomarker of polycyclic aromatic hydrocarbons exposure in adulthood. Thus, they may be used as a proxy of urban environmental exposure.

1459Socioeconomic position influence on the early-life individual exposome in the Italian NINFEA birth cohort

Abstract Background Early exposure to unhealthy lifestyles and environmental risk factors is known to affect health throughout the life-course. There is also evidence that the exposure patterns are influenced by the socioeconomic position (SEP). Methods We use the data of the Turin participants of the Italian NINFEA birth cohort (n∼2500) to study how family SEP drives the early life exposome. SEP at birth is measured through the EHII (Equivalized Household Income Indicator), while the exposome includes urban environment, diet and lifestyle exposures measured during infancy. We use standard regression models to evaluate the effect of EHII on each exposome variable accounting for multiple comparison and potential confounders (Drivers-Exposome Wide Association Study – DExWAS) and the hierarchical clustering on the principal components approach to identify groups with similar exposure pattern. Results The DExWAS show that low EHII is associated with lower consumption of fruit and vegetables, lower levels of NO2, building and facilities densities, traffic, walkability and connectivity index, higher land-use diversity index, and higher exposure to pets. The hierarchical cluster analysis identifies three groups, with subjects belonging to the cluster characterized by higher level of urban environment risk factors and a healthier diet having a higher mean EHII. Conclusions These SEP-early life exposome analyses will be replicated in several European birth cohorts participating in the H2020 ATHLETE and LifeCycle projects. Key messages In the Italian city of Turin children from low SEP family are exposed to higher levels of environmental risk factors and unhealthy lifestyles during infancy.

Urban Environment and Growth and Obesity in Preschool Children from Six European Birth Cohorts

BACKGROUND AND AIM: Urban environmental exposures have been investigated separately in relation to growth and childhood obesity. In this study we aim to determine which prenatal and postnatal outdoor exposures are associated with childhood BMI, weight and height at age 3-4 years. METHODS: Height and weight were measured in 11,325 children aged 3-4 years from a multi-centre European cohort (France, Greece, Lithuania, Norway, Spain, and UK). BMI was calculated using the formula weight/height². Age-and-sex–standardized {z}-scores were calculated for height, weight and BMI. Urban environment exposures were estimated during pregnancy and childhood, including air pollution, built environment, green spaces, traffic, noise, meteorology, and socioeconomic deprivation index. Exposure-wide association study was performed using multiple single exposure linear regression models and accounting for multiple testing. RESULTS:Non linear associations were observed between exposure to Normalized Difference Vegetation Index (NDVI), a measure of greeness, and the outcomes leading to its categorization into tertiles. Pregnancy and postnatal NDVI in the first tertile were associated with greater height compared to the reference (second tertile), and remained statistically significant after correction for multiple testing (prenatal corrected {p}-value threshold for significance = 0.002; postnatal corrected {p}-value = 0.003). Other prenatal and postnatal markers of the urban environment such as walkability, building density and land use, nitrogen dioxide and fine particles were also associated with greater height, but were no longer statistically significant after correction for multiple testing. Fine particles during pregnancy were associated with higher BMI, and prenatal NDVI in the first tertile and air pollution were also associated with higher weight, but the {p}-values for these associations were above the corrected threshold for multiple testing. CONCLUSIONS:Living in a less green and more densely built and walkable area may affect preschool height in a positve manner. KEYWORDS: External exposome, Green space, Built environment, Children's environmental health, Obesity and metabolic disorders

Early life environmental exposures have a minor impact on the gut ecosystem following a natural birth

ABSTRACT A growing body of evidence suggests that the environment is an important source of colonizing bacteria for the gastrointestinal tract of C-section delivered infants, who undergo multiple birth-related interventions; however, the extent to which environmental microbes impact vaginally delivered infants remains unclear. Here we investigated the impact of rural and urban environmental exposures on microbial establishment and immunity in vaginally delivered mice. We simulated rural and urban home environments by adding soil types to cages from breeding to weaning. Our aims were to determine the impact of rural and urban soil exposures on the gut microbiome in young mice and to understand whether these changes persisted into adulthood. Host immune cytokines and microbial short-chain fatty acids were quantified to understand the impact on immunity. We found that early-life soil exposure had a minor effect on the richness of the neonatal gut microbiota contributing 5% and 9% variation in the bacterial community structure between mice during early-life and adulthood, respectively. Exposure to urban soil increased Clostridiaceae and propionic acid which persisted into adulthood. While soil exposure had a limited effect on the gut taxa, systemic cytokine and chemokine profiles were altered in adulthood. The findings presented here show that unlike in C-section deliveries previously reported, environmental exposures following a natural birth have a limited impact on the gut microbial taxa but potentially play an important role in immune-mediated disease susceptibility later in life.