The Urban Environment and Cardiometabolic Health.

Urban environments contribute substantially to the rising burden of cardiometabolic diseases worldwide. Cities are complex adaptive systems that continually exchange resources, shaping exposures relevant to human health such as air pollution, noise, and chemical exposures. In addition, urban infrastructure and provisioning systems influence multiple domains of health risk, including behaviors, psychological stress, pollution, and nutrition through various pathways (eg, physical inactivity, air pollution, noise, heat stress, food systems, the availability of green space, and contaminant exposures). Beyond cardiometabolic health, city design may also affect climate change through energy and material consumption that share many of the same drivers with cardiometabolic diseases. Integrated spatial planning focusing on developing sustainable compact cities could simultaneously create heart-healthy and environmentally healthy city designs. This article reviews current evidence on the associations between the urban exposome (totality of exposures a person experiences, including environmental, occupational, lifestyle, social, and psychological factors) and cardiometabolic diseases within a systems science framework, and examines urban planning principles (eg, connectivity, density, diversity of land use, destination accessibility, and distance to transit). We highlight critical knowledge gaps regarding built-environment feature thresholds for optimizing cardiometabolic health outcomes. Last, we discuss emerging models and metrics to align urban development with the dual goals of mitigating cardiometabolic diseases while reducing climate change through cross-sector collaboration, governance, and community engagement. This review demonstrates that cities represent crucial settings for implementing policies and interventions to simultaneously tackle the global epidemics of cardiovascular disease and climate change.

Cooling cities through urban green infrastructure: a health impact assessment of European cities.

BACKGROUND: High ambient temperatures are associated with many health effects, including premature mortality. The combination of global warming due to climate change and the expansion of the global built environment mean that the intensification of urban heat islands (UHIs) is expected, accompanied by adverse effects on population health. Urban green infrastructure can reduce local temperatures. We aimed to estimate the mortality burden that could be attributed to UHIs and the mortality burden that would be prevented by increasing urban tree coverage in 93 European cities. METHODS: We did a quantitative health impact assessment for summer (June 1-Aug 31), 2015, of the effect of UHIs on all-cause mortality for adults aged 20 years or older in 93 European cities. We also estimated the temperature reductions that would result from increasing tree coverage to 30% for each city and estimated the number of deaths that could be potentially prevented as a result. We did all analyses at a high-resolution grid-cell level (250 × 250 m). We propagated uncertainties in input analyses by using Monte Carlo simulations to obtain point estimates and 95% CIs. We also did sensitivity analyses to test the robustness of our estimates. FINDINGS: The population-weighted mean city temperature increase due to UHI effects was 1·5°C (SD 0·5; range 0·5-3·0). Overall, 6700 (95% CI 5254-8162) premature deaths could be attributable to the effects of UHIs (corresponding to around 4·33% [95% CI 3·37-5·28] of all summer deaths). We estimated that increasing tree coverage to 30% would cool cities by a mean of 0·4°C (SD 0·2; range 0·0-1·3). We also estimated that 2644 (95% CI 2444-2824) premature deaths could be prevented by increasing city tree coverage to 30%, corresponding to 1·84% (1·69-1·97) of all summer deaths. INTERPRETATION: Our results showed the deleterious effects of UHIs on mortality and highlighted the health benefits of increasing tree coverage to cool urban environments, which would also result in more sustainable and climate-resilient cities. FUNDING: GoGreenRoutes, Spanish Ministry of Science and Innovation, Institute for Global Health, UK Medical Research Council, European Union's Horizon 2020 Project Exhaustion.

Urban green spaces and behavioral and cognitive development in children: A health impact assessment of the Barcelona "Eixos Verds" Plan (Green Axis Plan).

BACKGROUND: Urban environments lack natural features, while nature exposure in cities has been associated with health benefits, including children's neurodevelopment. Through extensive street greening, Barcelona's Eixos Verds (Green Axis) Plan enhances safety, environment, and climate resilience. We aimed to assess the Eixos Verds Plan's potential impact on children's behavioral and cognitive development due to the increased green space expected under the Eixos Verds implementation. METHODS: We performed a quantitative health impact assessment for Barcelona children at census-tract level (n = 1068). We assessed the Eixos Verds Plan's impact by comparing baseline green space distribution with the proposed plan, translating it into percentage green area (%GA) and Normalized Difference Vegetation Index (NDVI). By combining these exposure metrics with child-specific risk estimates and population data, we estimated potential improvements in children's behavioral and cognitive development due to full Eixos Verds implementation. RESULTS: With the full Eixos Verds implementation, citywide, %GA increased by 6.9% (IQR: 6.4%; range: 0-23.1%) and NDVI by 0.065 (IQR: 0.083; range: 0.000-0.194). Child behavioral and cognitive development outcomes are expected to improve compared to the baseline. Based on NDVI increases, children's Total Difficulties and Hyperactivity/Inattention scores, based on the Strengths and Difficulties Questionnaire (SDQ), are projected to decrease by 5% (95% CI: 0-15%) and 6% (95% CI: 0-17%). Working Memory and Superior Working Memory scores are expected to increase by 4% and 5%, respectively, based on the computerized n-back test, while the Inattentiveness score could be reduced by 1%, based on the computerized attentional test (ANT). INTERPRETATION: Urban greening as planning tool can improve behavioral and cognitive development in city children. Methods and results of our study are applicable to many cities worldwide, and similar results for children of real-life urban greening interventions can be expected.

Mechanisms underlying the associations between different types of nature exposure and sleep duration: An 18-country analysis.

Whilst green space has been linked to healthier sleep outcomes, the roles of specific types of nature exposure, potential underlying mechanisms, and between-country variations in nature-sleep associations have received little attention. Drawing on cross-sectional survey data from an 18-country sample of adults (N = 16,077) the current study examined: 1) the relative associations between six different types of nature exposure (streetscape greenery, blue view from home, green space within 1 km, coast within 1 km, green space visits, blue space visits) and insufficient sleep (<6 h vs. 7-10 h per day); 2) whether these relationships were mediated by better mental wellbeing and/or physical activity; and 3) the consistency of these pathways among the different countries. After controlling for covariates, neighbourhood nature measures (green space, coast within 1 km) were not significantly associated with insufficient sleep; but nature visible from home (streetscape greenery, blue views) and recreational visits to green and blue spaces were each associated with less insufficient sleep. Significant nature-sleep associations were mediated, to varying degrees, by better mental wellbeing, but not self-reported physical activity. Country-level heterogeneity in the strength of nature-sleep associations was observed. Increasing nature visible from the home may represent a promising strategy for promoting healthier sleep duration at the population level, whilst nature-based interventions encouraging individuals to spend time in local green/blue spaces may be an appropriate target to assist individuals affected by insufficient sleep.

Associations between combined urban and lifestyle factors and respiratory health in European children.

INTRODUCTION: Previous studies identified some environmental and lifestyle factors independently associated with children respiratory health, but few focused on exposure mixture effects. This study aimed at identifying, in pregnancy and in childhood, combined urban and lifestyle environment profiles associated with respiratory health in children. METHODS: This study is based on the European Human Early-Life Exposome (HELIX) project, combining six birth cohorts. Associations between profiles of pregnancy (38 exposures) and childhood (84 exposures) urban and lifestyle factors, identified by clustering analysis, and respiratory health were estimated by regression models adjusted for confounders. RESULTS: Among the 1033 included children (mean ± standard-deviation (SD) age: 8.2 ± 1.6 years old, 47% girls) the mean ± SD forced expiratory volume in 1s (FEV1) and forced vital capacity (FVC) were 99 ± 13% and 101 ± 14%, respectively, and 12%, 12% and 24% reported ever-asthma, wheezing and rhinitis, respectively. Four profiles of pregnancy exposures and four profiles of childhood exposures were identified. Compared to the reference childhood exposure profile (low exposures), two exposure profiles were associated with lower levels of FEV1. One profile was characterized by few natural spaces in the surroundings and high exposure to the built environment and road traffic. The second profile was characterized by high exposure to meteorological factors and low levels of all other exposures and was also associated with an increased risk of ever-asthma and wheezing. A pregnancy exposure profile characterized by high exposure levels to all risk factors, but a healthy maternal lifestyle, was associated with a lower risk of wheezing and rhinitis in children, compared to the reference pregnancy profile (low exposures). CONCLUSION: This comprehensive approach revealed pregnancy and childhood profiles of urban and lifestyle exposures associated with lung function and/or respiratory conditions in children. Our findings highlight the need to pursue the study of combined exposures to improve prevention strategies for multifactorial diseases such as asthma.

Exploring the nexus of urban form, transport, environment and health in large-scale urban studies: A state-of-the-art scoping review.

BACKGROUND: As the world becomes increasingly urbanised, there is recognition that public and planetary health relies upon a ubiquitous transition to sustainable cities. Disentanglement of the complex pathways of urban design, environmental exposures, and health, and the magnitude of these associations, remains a challenge. A state-of-the-art account of large-scale urban health studies is required to shape future research priorities and equity- and evidence-informed policies. OBJECTIVES: The purpose of this review was to synthesise evidence from large-scale urban studies focused on the interaction between urban form, transport, environmental exposures, and health. This review sought to determine common methodologies applied, limitations, and future opportunities for improved research practice. METHODS: Based on a literature search, 2958 articles were reviewed that covered three themes of: urban form; urban environmental health; and urban indicators. Studies were prioritised for inclusion that analysed at least 90 cities to ensure broad geographic representation and generalisability. Of the initially identified studies, following expert consultation and exclusion criteria, 66 were included. RESULTS: The complexity of the urban ecosystem on health was evidenced from the context dependent effects of urban form variables on environmental exposures and health. Compact city designs were generally advantageous for reducing harmful environmental exposure and promoting health, with some exceptions. Methodological heterogeneity was indicative of key urban research challenges; notable limitations included exposure and health data at varied spatial scales and resolutions, limited availability of local-level sociodemographic data, and the lack of consensus on robust methodologies that encompass best research practice. CONCLUSION: Future urban environmental health research for evidence-informed urban planning and policies requires a multi-faceted approach. Advances in geospatial and AI-driven techniques and urban indicators offer promising developments; however, there remains a wider call for increased data availability at local-levels, transparent and robust methodologies of large-scale urban studies, and greater exploration of urban health vulnerabilities and inequities.

Childhood exposure to outdoor air pollution in different microenvironments and cognitive and fine motor function in children from six European cohorts.

BACKGROUND: Exposure to air pollution during childhood has been linked with adverse effects on cognitive development and motor function. However, limited research has been done on the associations of air pollution exposure in different microenvironments such as home, school, or while commuting with these outcomes. OBJECTIVE: To analyze the association between childhood air pollution exposure in different microenvironments and cognitive and fine motor function from six European birth cohorts. METHODS: We included 1301 children from six European birth cohorts aged 6-11 years from the HELIX project. Average outdoor air pollutants concentrations (NO2, PM2.5) were estimated using land use regression models for different microenvironments (home, school, and commute), for 1-year before the outcome assessment. Attentional function, cognitive flexibility, non-verbal intelligence, and fine motor function were assessed using the Attention Network Test, Trail Making Test A and B, Raven Colored Progressive Matrices test, and the Finger Tapping test, respectively. Adjusted linear regressions models were run to determine the association between each air pollutant from each microenvironment on each outcome. RESULTS: In pooled analysis we observed high correlation (rs = 0.9) between air pollution exposures levels at home and school. However, the cohort-by-cohort analysis revealed correlations ranging from low to moderate. Air pollution exposure levels while commuting were higher than at home or school. Exposure to air pollution in the different microenvironments was not associated with working memory, attentional function, non-verbal intelligence, and fine motor function. Results remained consistently null in random-effects meta-analysis. CONCLUSIONS: No association was observed between outdoor air pollution exposure in different microenvironments (home, school, commute) and cognitive and fine motor function in children from six European birth cohorts. Future research should include a more detailed exposure assessment, considering personal measurements and time spent in different microenvironments.

The Superblock model: A review of an innovative urban model for sustainability, liveability, health and well-being.

INTRODUCTION: Current urban and transport planning practices have significant negative health, environmental, social and economic impacts in most cities. New urban development models and policies are needed to reduce these negative impacts. The Superblock model is one such innovative urban model that can significantly reduce these negative impacts through reshaping public spaces into more diverse uses such as increase in green space, infrastructure supporting social contacts and physical activity, and through prioritization of active mobility and public transport, thereby reducing air pollution, noise and urban heat island effects. This paper reviews key aspects of the Superblock model, its implementation and initial evaluations in Barcelona and the potential international uptake of the model in Europe and globally, focusing on environmental, climate, lifestyle, liveability and health aspects. METHODS: We used a narrative meta-review approach and PubMed and Google scholar databases were searched using specific terms. RESULTS: The implementation of the Super block model in Barcelona is slow, but with initial improvement in, for example, environmental, lifestyle, liveability and health indicators, although not so consistently. When applied on a large scale, the implementation of the Superblock model is not only likely to result in better environmental conditions, health and wellbeing, but can also contribute to the fight against the climate crisis. There is a need for further expansion of the program and further evaluation of its impacts and answers to related concerns, such as environmental equity and gentrification, traffic and related environmental exposure displacement. The implementation of the Superblock model gained a growing international reputation and variations of it are being planned or implemented in cities worldwide. Initial modelling exercises showed that it could be implemented in large parts of many cities. CONCLUSION: The Superblock model is an innovative urban model that addresses environmental, climate, liveability and health concerns in cities. Adapted versions of the Barcelona Superblock model are being implemented in cities around Europe and further implementation, monitoring and evaluation are encouraged. The Superblock model can be considered an important public health intervention that will reduce mortality and morbidity and generate cost savings for health and other sectors.

The methodology of quantitative risk assessment studies.

Once an external factor has been deemed likely to influence human health and a dose response function is available, an assessment of its health impact or that of policies aimed at influencing this and possibly other factors in a specific population can be obtained through a quantitative risk assessment, or health impact assessment (HIA) study. The health impact is usually expressed as a number of disease cases or disability-adjusted life-years (DALYs) attributable to or expected from the exposure or policy. We review the methodology of quantitative risk assessment studies based on human data. The main steps of such studies include definition of counterfactual scenarios related to the exposure or policy, exposure(s) assessment, quantification of risks (usually relying on literature-based dose response functions), possibly economic assessment, followed by uncertainty analyses. We discuss issues and make recommendations relative to the accuracy and geographic scale at which factors are assessed, which can strongly influence the study results. If several factors are considered simultaneously, then correlation, mutual influences and possibly synergy between them should be taken into account. Gaps or issues in the methodology of quantitative risk assessment studies include 1) proposing a formal approach to the quantitative handling of the level of evidence regarding each exposure-health pair (essential to consider emerging factors); 2) contrasting risk assessment based on human dose-response functions with that relying on toxicological data; 3) clarification of terminology of health impact assessment and human-based risk assessment studies, which are actually very similar, and 4) other technical issues related to the simultaneous consideration of several factors, in particular when they are causally linked.

Associations of Maternal Educational Level, Proximity to Greenspace During Pregnancy, and Gestational Diabetes With Body Mass Index From Infancy to Early Adulthood: A Proof-of-Concept Federated Analysis in 18 Birth Cohorts.

International sharing of cohort data for research is important and challenging. We explored the feasibility of multi-cohort federated analyses by examining associations between three pregnancy exposures (maternal education, exposure to green vegetation and gestational diabetes) with offspring BMI from infancy to 17 years. We used data from 18 cohorts (n=206,180 mother-child pairs) from the EU Child Cohort Network and derived BMI at ages 0-1, 2-3, 4-7, 8-13 and 14-17 years. Associations were estimated using linear regression via one-stage IPD meta-analysis using DataSHIELD. Associations between lower maternal education and higher child BMI emerged from age 4 and increased with age (difference in BMI z-score comparing low with high education age 2-3 years = 0.03 [95% CI 0.00, 0.05], 4-7 years = 0.16 [95% CI 0.14, 0.17], 8-13 years = 0.24 [95% CI 0.22, 0.26]). Gestational diabetes was positively associated with BMI from 8 years (BMI z-score difference = 0.18 [CI 0.12, 0.25]) but not at younger ages; however associations attenuated towards the null when restricted to cohorts which measured GDM via universal screening. Exposure to green vegetation was weakly associated with higher BMI up to age one but not at older ages. Opportunities of cross-cohort federated analyses are discussed.

Exposure to low-level ambient air pollution and the relationship with lung and bladder cancer in older men, in Perth, Western Australia.

BACKGROUND: Air pollution is a cause of lung cancer and is associated with bladder cancer. However, the relationship between air pollution and these cancers in regions of low pollution is unclear. We investigated associations between fine particulate matter (PM2.5), nitrogen dioxide, and black carbon (BC), and both these cancers in a low-pollution city. METHODS: A cohort of 11,679 men ≥65 years old in Perth (Western Australia) were followed from 1996-1999 until 2018. Pollutant concentrations, as a time-varying variable, were estimated at participants' residential addresses using land use regression models. Incident lung and bladder cancer were identified through the Western Australian Cancer Registry. Risks were estimated using Cox proportional-hazard models (age as the timescale), adjusting for smoking, socioeconomic status, and co-pollutants. RESULTS: Lung cancer was associated with PM2.5 and BC in the adjusted single-pollutant models. A weak positive association was observed between ambient air pollution and squamous cell lung carcinoma but not lung adenocarcinoma. Positive associations were observed with bladder cancer, although these were not statistically significant. Associations were attenuated in two-pollutant models. CONCLUSION: Low-level ambient air pollution is associated with lung, and possibly bladder, cancer among older men, suggesting there is no known safe level for air pollution as a carcinogen.

Prenatal environmental exposures associated with sex differences in childhood obesity and neurodevelopment.

BACKGROUND: Obesity and neurodevelopmental delay are complex traits that often co-occur and differ between boys and girls. Prenatal exposures are believed to influence children's obesity, but it is unknown whether exposures of pregnant mothers can confer a different risk of obesity between sexes, and whether they can affect neurodevelopment. METHODS: We analyzed data from 1044 children from the HELIX project, comprising 93 exposures during pregnancy, and clinical, neuropsychological, and methylation data during childhood (5-11 years). Using exposome-wide interaction analyses, we identified prenatal exposures with the highest sexual dimorphism in obesity risk, which were used to create a multiexposure profile. We applied causal random forest to classify individuals into two environments: E1 and E0. E1 consists of a combination of exposure levels where girls have significantly less risk of obesity than boys, as compared to E0, which consists of the remaining combination of exposure levels. We investigated whether the association between sex and neurodevelopmental delay also differed between E0 and E1. We used methylation data to perform an epigenome-wide association study between the environments to see the effect of belonging to E1 or E0 at the molecular level. RESULTS: We observed that E1 was defined by the combination of low dairy consumption, non-smokers' cotinine levels in blood, low facility richness, and the presence of green spaces during pregnancy (ORinteraction = 0.070, P = 2.59 × 10-5). E1 was also associated with a lower risk of neurodevelopmental delay in girls, based on neuropsychological tests of non-verbal intelligence (ORinteraction = 0.42, P = 0.047) and working memory (ORinteraction = 0.31, P = 0.02). In line with this, several neurodevelopmental functions were enriched in significant differentially methylated probes between E1 and E0. CONCLUSIONS: The risk of obesity can be different for boys and girls in certain prenatal environments. We identified an environment combining four exposure levels that protect girls from obesity and neurodevelopment delay. The combination of single exposures into multiexposure profiles using causal inference can help determine populations at risk.

Health and economic benefits of meeting WHO air quality guidelines, Western Pacific Region.

Objective: To quantify the number of avoidable annual deaths and associated economic benefits from meeting the World Health Organization (WHO) air quality guidelines for ambient concentrations for fine particulate matter (PM2.5) for Member States of the WHO Western Pacific Region. Methods: Using the AirQ+ software, we performed a quantitative health impact assessment comparing country-level PM2.5 concentrations with the 2005 and 2021 air quality guidelines recommended maximum concentrations of 10 and 5 µg/m3, respectively. We obtained PM2.5 data from the WHO Global Health Observatory (latest available year 2016), and population and mortality estimates from the United Nations World Population Prospects database for the latest 5-year period available (2015-2019), which we averaged to 1-year estimates. A risk estimate for all-cause mortality, based on a meta-analysis, was embedded within AirQ+ software. Our economic assessment used World Bank value of a statistical life adjusted to country-specific gross domestic product (latest available year 2014). Findings: Data were complete for 21 of 27 Member States. If these countries achieved the 2021 guidelines for PM2.5, an estimated 3.1 million deaths would be avoided annually, which are 0.4 million more deaths avoided than meeting the 2005 guidelines. China would avoid the most deaths per 100 000 population (303 deaths) and Brunei Darussalam the least (5 deaths). The annual economic benefit per capita ranged from 5781 United States dollars (US$) in Singapore to US$ 143 in Solomon Islands. Conclusion: Implementing effective measures to reduce PM2.5 emissions would save a substantial number of lives and money across the Region.

Public Health-Led Insights on Electric Micro-mobility Adoption and Use: a Scoping Review.

The advent of electric micro-mobility (EMM) has transformed the urban mobility landscape, with projections indicating a 5-10% increase in its modal share in European cities by 2030. In this scoping review, we aimed to comprehensively examine the key determinants of EMM adoption and usage from a public health perspective. Sixty-seven articles were included in the analysis, primarily covering e-bikes and e-scooters. The determinants were categorised into two broad categories: (1) contextual determinants that encompass enabling and hindering factors related to legal frameworks, transportation systems and infrastructure, and technology, and (2) individual-level determinants that pertain to intrinsic motivations and deterrents of individuals. Our findings reveal that EMM vehicles are widely perceived as a cost-effective, flexible, ad hoc, and fast mode of transportation within urban areas, augmenting accessibility and connectivity. Additionally, the lightweight, foldable, and transportable nature of these vehicles is highly appreciated by users. However, several barriers have also been identified, including inadequate infrastructure and end-of-trip facilities, limited capability to traverse diverse terrains and trip scenarios, acquisition and maintenance costs, limited carrying capacities, technical failures, and accident risks. Our results suggest that the interplay of contextual enablers and barriers and personal motivations and deterrents drive the emergence, adoption, and usage of EMM. Hence, a comprehensive understanding of both contextual and individual-level determinants is crucial for ensuring a sustainable and healthy uptake of EMM.

Health impact assessments of shipping and port-sourced air pollution on a global scale: A scoping literature review.

BACKGROUND: Globalisation has led to international trade expand rapidly. Seaborne transport moves 80% of traded goods across the globe, producing around 3% of greenhouse gases and other hazardous pollutants, such as PM, NOx and SOx, known to be harmful to health. METHODS: A scoping literature review was conducted reviewing peer-reviewed studies on health impact assessments (HIA) of global shipping and port-sourced air pollution. For review inclusion, studies had to (1) use a HIA methodology; (2) quantify the air pollution concentration attributable to at least one shipping or port activity scenario; (3) assess at least one health outcome (i.e. epidemiological measure or monetization); (4) quantify the attributable health burden of the respective scenario. RESULTS: Thirty-two studies were included, studying predominantly European Sea shipping/ port-sourced emissions with health impacts for global or respective European populations. Also, Global, Asian, North American and Australian Sea shipping/ port-sourced emissions were studied, with attributable health impacts for global or respective populations. The health outcome predominantly studied was mortality (all-cause, cause-specific, loss in life expectancy, years of life lost (YLLs)), but also morbidity (disease cases, hospital admissions, years lived with disability (YLDs)), disability-adjusted life-years (DALYs), restricted activity days and work loss days. The highest air pollution concentrations were identified along major shipping routes and ports, and the strongest health impacts occurred among respective riparian populations. Globally, ∼265,000 premature deaths were projected for 2020 (∼0.5% of global mortality) attributable to global shipping-sourced emissions. Emission control scenarios studied were predominantly sulphur fuel content caps and NOx emission reduction scenarios, consisting of technological interventions, cleaner fuels or fuel switches, and were assessed as effective in reducing shipping-sourced emissions, and hence, health burdens. CONCLUSIONS: Our review positions maritime transport an important source of air pollution and health risk factor, which needs more research and policy attention and rigorous emission control efforts, as shipping-sourced emissions are projected to increase with increases in global trade and shipping volumes.

Environmental health impacts and inequalities in green space and air pollution in six medium-sized European cities.

BACKGROUND: The GoGreenRoutes project aims to introduce co-created nature-based solutions (NBS) to enhance environmental quality in six medium-sized cities (Burgas, Lahti, Limerick, Tallinn, Umeå, and Versailles). We estimated the mortality and economic impacts attributed to suboptimal exposure to green space and air pollution, economic impacts, and the distribution thereof the adult population by socioeconomic status. METHODS: We retrieved data from publicly accessible databases on green space (NDVI and % Green Area), air pollution (NO2 and PM2.5) and population (≥20 years, n = 804,975) at a 250m × 250m grid-cell level, and mortality for each city for 2015. We compared baseline exposures at the grid-cell to World Health Organization's recommendations and guidelines. We applied a comparative risk assessment to estimate the mortality burden attributable to not achieving the recommendations and guidelines. We estimated attributable mortality distributions and the association with income levels. RESULTS: We found high variability in air pollution and green spaces levels. Around 60% of the population lacked green space and 90% were exposed to harmful air pollution. Overall, we estimated age-standardized mortality rates varying from 10 (Umeå) to 92 (Burgas) deaths per 100,000 persons attributable to low NDVI levels; 3 (Lahti) to 38 (Burgas) per 100,000 persons to lack of % Green Area; 1 (Umeå) to 88 (Tallinn) per 100,000 persons to exceedances of NO2 guidelines; and 1 (Umeå) to 206 (Burgas) per 100,000 persons to exceedances of PM2.5 guidelines. Lower income associated with higher or lower mortality impacts depending on whether deprived populations lived in the densely constructed, highly-trafficked city centre or greener, less polluted outskirts. CONCLUSIONS: We attributed a considerable mortality burden to lack of green spaces and higher air pollution, which was unevenly distributed across different social groups. NBS and health-promoting initiatives should consider socioeconomic aspects to regenerate urban areas while providing equally good environments.

Restoration in mental health after visiting urban green spaces, who is most affected? Comparison between good/poor mental health in four European cities.

Several mechanisms have been proposed to explain the association between green space and health, and one of these is the restoration theory, based on the idea that it is possible to increase mental health and decrease stress visiting a natural environment. The aims of the present study were to understand what activities are most related to restoration and if these are the same for people with poorer and better mental health. A questionnaire was administered in four European cities and data about restoration outcomes, type of activity carried out in green spaces and mental health were collected and analyzed. A cross sectional design was used and total of 3134 respondents participated to the questionnaire. The restoration experience was measured with the restoration outcome score, and the mental health was evaluated with a subscale related to mental health of the Medical Outcome Short Form. Participants were divided in two groups according to mental health score. A multiple regression analysis was performed to investigate the association between mental health, type of activity and restoration. The cities showed a similar trend in the association between restoration and type of activity performed in green environment. People with poorer mental health seem to be more sensitive to the positive effect of visiting the green environment and restoration was more evident in these people than in those with better mental health. At the same time, the type of activity was less evident in people with better mental health, and they seemed to be less influenced by the visiting of green space. Green prescription is important for the entire population: people with poorer mental health could have important restorative effects and people with better mental health could continue to protect their well-being using green space.

Environmental exposures in early-life and general health in childhood.

BACKGROUND: Early-life environmental exposures are suspected to be involved in the development of chronic diseases later in life. Most studies conducted so far considered single or few exposures and single-health parameter. Our study aimed to identify a childhood general health score and assess its association with a wide range of pre- and post-natal environmental exposures. METHODS: The analysis is based on 870 children (6-12 years) from six European birth cohorts participating in the Human Early-Life Exposome project. A total of 53 prenatal and 105 childhood environmental factors were considered, including lifestyle, social, urban and chemical exposures. We built a general health score by averaging three sub-scores (cardiometabolic, respiratory/allergy and mental) built from 15 health parameters. By construct, a child with a low score has a low general health status. Penalized multivariable regression through Least Absolute Shrinkage and Selection Operator (LASSO) was fitted in order to identify exposures associated with the general health score. FINDINGS: The results of LASSO show that a lower general health score was associated with maternal passive and active smoking during pregnancy and postnatal exposure to methylparaben, copper, indoor air pollutants, high intake of caffeinated drinks and few contacts with friends and family. Higher child's general health score was associated with prenatal exposure to a bluespace near residency and postnatal exposures to pets, cobalt, high intakes of vegetables and more physical activity. Against our hypotheses, postnatal exposure to organochlorine compounds and perfluorooctanoate were associated with a higher child's general health score. CONCLUSION: By using a general health score summarizing the child cardiometabolic, respiratory/allergy and mental health, this study reinforced previously suspected environmental factors associated with various child health parameters (e.g. tobacco, air pollutants) and identified new factors (e.g. pets, bluespace) warranting further investigations.

Vegetation and vehicle emissions around primary schools across urban Australia: associations with academic performance.

BACKGROUND: Evolving evidence suggests that vegetation surrounding schools is beneficial to children's academic performance, however vehicle emissions are adversely related. Little is known about concurrent impacts of vegetation and vehicle emissions on academic performance. This study examined associations of vegetation and vehicle emissions near urban Australian primary schools with children's academic performance. METHODS: Vegetation within schoolyards and Euclidean buffers (100, 300 and 1000 m) was assessed using the Normalized Difference Vegetation Index (NDVI). Weighted road density (WRD) was computed for each buffer as a vehicle emissions proxy. Cross-sectional associations and mediating pathways between vegetation and vehicle emissions and standardized average academic scores in Literacy (Reading, Writing, Language Conventions) and Mathematics for Grades 3 and 5 attending 3745 primary schools in urban areas (population ≥10,000) of Australia in 2018 were assessed using generalised linear models adjusted for school socio-educational status. RESULTS: Significant positive associations were found between vegetation and Reading in Grades 3 and 5, Mathematics in Grade 3 (all buffers), Writing in Grade 3 (100 and 300 m), and Language Conventions in Grades 3 and 5 (most buffers). Increased vehicle emissions were negatively associated with Reading and Mathematics in Grades 3 and 5 (most buffers), and Language Conventions in Grade 3 (300 and 1000 m) and Grade 5 (100-1000 m). Within 300 m, vehicle emissions partially mediated associations between vegetation with Mathematics in Grade 3 (proportion mediated, 21%), Reading and Language Conventions in Grade 5 (15%, 37% respectively). CONCLUSIONS: Our findings contribute to growing evidence that vegetation around primary schools is associated with higher achievement in Literacy and Mathematics, with partial mediation by vehicle emissions. Future studies should conduct on-site measurement of vehicle emissions and audit vegetation around schools to confirm findings and inform urban/school planners and school leaders on designing and modifying school environments to support learning.

The evaluation of the 3-30-300 green space rule and mental health.

BACKGROUND AND AIMS: Urban green space has many health benefits, but it is still unclear how much actually is needed for better health. Recently a new 3-30-300 rule of thumb for urban forestry and urban greening has been proposed, but this rule has not been evaluated for benefits on health. The rule requires that every citizen should be able to see at least three trees from their home, have 30 percent tree canopy cover in their neighbourhood and not live more than 300 m away from the nearest park or green space. The aim of this study was to evaluate the relationship between the 3-30-300 green space rule and its components in relation to mental health. METHODS: We conducted a cross-sectional study based on a population-based sample of 3145 individuals aged 15-97 years from in Barcelona, Spain who participated in the Barcelona Health Survey (2016-2017). We created 3-30-300 green space indicators using questionnaire data, GIS, remote sensing and land cover maps. Mental health status was assessed with the 12-item General Health Questionnaire (GHQ-12) and also the use of tranquilizer/sedatives or antidepressants and psychiatrist or psychologist visits. Analyses were conducted using mixed effects logistic regression models with districts as the random effect, adjusted for relevant covariates. RESULTS: We found that people in Barcelona had relatively little exposure to green space, whether through window view, living in an area with sufficient greenness, or access to a major green space, and only 4.7% met a surrogate 3-30-300 green space rule. Residential surrounding greenness, but not tree window view or access to major green space, was significantly associated with better mental health, less medication use, and fewer psychologist or psychiatrist visits. Meeting the full surrogate 3-30-300 green space rule was associated with better mental health, less medication use, and fewer psychologist or psychiatrist visits, but only for the latter combined the association was statistically significant (Odds ratio = 0.31, 95% CI: 0.11, 0.91). CONCLUSION: Few people achieved the 3-30-300 green space in Barcelona and we used a surrogate measure. We observed health benefits when the full surrogate rule was met.