March 26| 2018

The Association between Lifelong Greenspace Exposure and 3-Dimensional Brain Magnetic Resonance Imaging in Barcelona Schoolchildren

Payam Dadvand, Jesus Pujol, Dídac Macià, Gerard Martínez-Vilavella, Laura Blanco-Hinojo, Marion Mortamais, Mar Alvarez-Pedrerol, Raquel Fenoll, Mikel Esnaola, Albert Dalmau-Bueno, Mónica López-Vicente, Xavier Basagaña, Michael Jerrett, Mark J. Nieuwenhuijsen, and Jordi Sunyer

Environ Health Perspect; February 2018, Volume 126, Issue 2 https://doi.org/10.1289/EHP1876

ABSTRACT

BACKGROUND:

Proponents of the biophilia hypothesis believe that contact with nature, including green spaces, has a crucial role in brain development in children. Currently, however, we are not aware of evidence linking such exposure with potential effects on brain structure.

OBJECTIVE:

We determined whether lifelong exposure to residential surrounding greenness is associated with regional differences in brain volume based on 3-dimensional magnetic resonance imaging (3D MRI) among children attending primary school.

METHODS:

We performed a series of analyses using data from a subcohort of 253 Barcelona schoolchildren from the Brain Development and Air Pollution Ultrafine Particles in School Children (BREATHE) project. We averaged satellite-based normalized difference vegetation index (NDVI) across 100-m buffers around all residential addresses since birth to estimate each participant’s lifelong exposure to residential surrounding greenness, and we used high-resolution 3D MRIs of brain anatomy to identify regional differences in voxel-wise brain volume associated with greenness exposure. In addition, we performed a supporting substudy to identify regional differences in brain volume associated with measures of working memory (d′ from computerized n-back tests) and inattentiveness (hit reaction time standard error from the Attentional Network Task instrument) that were repeated four times over one year. We also performed a second supporting substudy to determine whether peak voxel tissue volumes in brain regions associated with residential greenness predicted cognitive function test scores.

RESULTS:

Lifelong exposure to greenness was positively associated with gray matter volume in the left and right prefrontal cortex and in the left premotor cortex and with white matter volume in the right prefrontal region, in the left premotor region, and in both cerebellar hemispheres. Some of these regions partly overlapped with regions associated with cognitive test scores (prefrontal cortex and cerebellar and premotor white matter), and peak volumes in these regions predicted better working memory and reduced inattentiveness.

CONCLUSION:

Our findings from a study population of urban schoolchildren in Barcelona require confirmation, but they suggest that being raised in greener neighborhoods may have beneficial effects on brain development and cognitive function.

March 19 | 2018

Associations Between the Built Environment and Objective Measures of Sleep: The Multi-Ethnic Study of Atherosclerosis.

Johnson DA, Hirsch JA, Moore KA, Redline S, Diez Roux AV.

Am J Epidemiol. 2018 Mar 14. doi: 10.1093/aje/kwx302. [Epub ahead of print] https://doi.org/10.1093/aje/kwx302

Abstract

Although dense neighborhood built environments support increased physical activity and lower obesity, these features may also disturb sleep. Therefore, we sought to understand the association between the built environment and objectively measured sleep. From 2010 to 2013, we analyzed data from examination 5 of the Multi-Ethnic Study of Atherosclerosis, a diverse population from 6 US cities. We fit multilevel models that assessed the association between the built environment (Street Smart Walk Score, social engagement destinations, street intersections, and population density) and sleep duration or efficiency from 1-week wrist actigraphy in 1,889 individuals. After adjustment for covariates, a 1-standard-deviation increase in Street Smart Walk Score was associated with 23% higher odds of short sleep duration (≤6 hours; odds ratio = 1.2, 95% confidence interval: 1.0, 1.4), as well as shorter average sleep duration (mean difference = -8.1 minutes, 95% confidence interval: -12.1, -4.2). Results were consistent across other built environment measures. Associations were attenuated after adjustment for survey-based measure of neighborhood noise. Dense neighborhood development may have multiple health consequence. In promoting denser neighborhoods to increase walkability, it is important to also implement strategies that reduce the adverse impacts of this development on sleep, such as noise reductions efforts.

March 12 | 2018

Gene-by-environment interactions in urban populations modulate risk phenotypes

Marie-Julie Favé, Fabien C. Lamaze, David Soave, Alan Hodgkinson, Héloïse Gauvin, Vanessa Bruat, Jean-Christophe Grenier, Elias Gbeha, Kimberly Skead, Audrey Smargiassi, Markey Johnson, Youssef Idaghdour & Philip Awadalla

Nature Communications volume 9, Article number: 827 (2018)  https://www.nature.com/articles/s41467-018-03202-2

 

ABSTRACT

Uncovering the interaction between genomes and the environment is a principal challenge of modern genomics and preventive medicine. While theoretical models are well defined, little is known of the G × E interactions in humans. We used an integrative approach to comprehensively assess the interactions between 1.6 million data points, encompassing a range of environmental exposures, health, and gene expression levels, coupled with whole-genome genetic variation. From ∼1000 individuals of a founder population in Quebec, we reveal a substantial impact of the environment on the transcriptome and clinical endophenotypes, overpowering that of genetic ancestry. Air pollution impacts gene expression and pathways affecting cardio-metabolic and respiratory traits, when controlling for genetic ancestry. Finally, we capture four expression quantitative trait loci that interact with the environment (air pollution). Our findings demonstrate how the local environment directly affects disease risk phenotypes and that genetic variation, including less common variants, can modulate individual’s response to environmental challenges.

Urban Green and Built Infrastructure as a Tool to Mitigate Local Air Pollution | April 10 | 2018 | VIDEO AVAILABLE

VIDEO NOW AVAILABLE

For his presentation, Dr. Baldauf will summarize the U.S. EPA’s research program on the use of built and green infrastructure to mitigate local air pollution impacts from transportation facilities.  His presentation will describe the current scientific understanding of how urban infrastructure affects local air quality, including a review of projects conducted in the US and other parts of the world investigating solid noise barrier and roadside vegetation impacts in particular.  He will also summarize existing resources developed by the U.S. EPA to assist environmental and health professionals, urban planners, and developers to identify best practices to mitigate local air pollution impacts and avoid unintended consequences where urban infrastructure may exacerbate local air quality concerns.

 

 

Dr. Baldauf has over 20 years of experience conducting research on emissions, air quality impacts, and adverse health effects from exposures to air pollution emitted by transportation and industrial sources.  His research focuses on the development of policies and practices to mitigate air pollution emissions and impacts at local, urban, and global scales.  His research has led to national emissions standards and best practices to mitigate air pollution impacts using urban development including built and green infrastructure.  He has a joint affiliation with the U.S. Environmental Protection Agency’s Office of Research & Development and the Office of Transportation & Air Quality where he has led cross-disciplinary research teams focusing on air quality measurements, air dispersion modeling, and sustainable transportation and urban development issues.  He also maintains Adjunct Professor appointments in the School of Engineering at North Carolina State University and Texas A&M University.  Dr. Baldauf co-manages the U.S. EPA’s Mobile Source Emissions Research Laboratory and led the cross-agency Sustainable Transportation Initiative.  He has published over 100 peer-review journal articles and several book chapters on these topics during his career at the U.S. EPA.

March 5 | 2018

Assessing the Exposome with External Measures: Commentary on the State of the Science and Research Recommendations

Michelle C. Turner, Mark Nieuwenhuijsen, Kim Anderson, David Balshaw, Yuxia Cui, Genevieve Dunton, Jane A. Hoppin, Petros Koutrakis, and Michael Jerrett

Annual Review of Public Health Vol. 38:215-239 (Volume publication date March 2017) https://doi.org/10.1146/annurev-publhealth-082516-012802

Abstract

The exposome comprises all environmental exposures that a person experiences from conception throughout the life course. Here we review the state of the science for assessing external exposures within the exposome. This article reviews (a) categories of exposures that can be assessed externally, (b) the current state of the science in external exposure assessment, (c) current tools available for external exposure assessment, and (d) priority research needs. We describe major scientific and technological advances that inform external assessment of the exposome, including geographic information systems; remote sensing; global positioning system and geolocation technologies; portable and personal sensing, including smartphone-based sensors and assessments; and self-reported questionnaire assessments, which increasingly rely on Internet-based platforms. We also discuss priority research needs related to methodological and technological improvement, data analysis and interpretation, data sharing, and other practical considerations, including improved assessment of exposure variability as well as exposure in multiple, critical life stages.

February 27 | 2018

Six research priorities for cities and climate change

Xuemei Bai, Richard J. Dawson, Diana Ürge-Vorsatz, Gian C. Delgado, Aliyu Salisu Barau, Shobhakar Dhakal, David Dodman, Lykke Leonardsen, Valerie Masson-Delmotte, Debra Roberts, Seth Schultz.

Nature 555, 23-25 (2018) doi: 10.1038/d41586-018-02409-z www.nature.com/articles/d41586-018-02409-z

Xuemei Bai and colleagues call for long-term, cross-disciplinary studies to reduce carbon emissions and urban risks from global warming.

February 19 | 2018

Impacts of Bicycle Infrastructure in Mid-Sized Cities (IBIMS): protocol for a natural experiment study in three Canadian cities

Meghan Winters, Michael Branion-Calles, Suzanne Therrien, Daniel Fuller, Lise Gauvin, David G T Whitehurst, and Trisalyn Nelson

BMJ Open. 2018; 8(1): e019130. Published online 2018 Jan 21. doi:  10.1136/bmjopen-2017-019130  PMCID: PMC5781157

Abstract

Introduction

Bicycling is promoted as a transportation and population health strategy globally. Yet bicycling has low uptake in North America (1%–2% of trips) compared with European bicycling cities (15%–40% of trips) and shows marked sex and age trends. Safety concerns due to collisions with motor vehicles are primary barriers.

To attract the broader population to bicycling, many cities are making investments in bicycle infrastructure. These interventions hold promise for improving population health given the potential for increased physical activity and improved safety, but such outcomes have been largely unstudied. In 2016, the City of Victoria, Canada, committed to build a connected network of infrastructure that separates bicycles from motor vehicles, designed to attract people of ‘all ages and abilities’ to bicycling.

This natural experiment study examines the impacts of the City of Victoria’s investment in a bicycle network on active travel and safety outcomes. The specific objectives are to (1) estimate changes in active travel, perceived safety and bicycle safety incidents; (2) analyse spatial inequities in access to bicycle infrastructure and safety incidents; and (3) assess health-related economic benefits.

February 12 | 2018

Effect of air quality alerts on human health: a regression discontinuity analysis in Toronto, Canada

Hong Chen, PhD, Qiongsi Li, MMath, Jay S Kaufman, PhD, Jun Wang, MSc, Ray Copes, MD, Yushan Su, PhD, Tarik Benmarhnia, PhD

The Lancet Planetary Health, Volume 2, No. 1, e19–e26, January 2018  DOI: https://doi.org/10.1016/S2542-5196(17)30185-7

Summary

Background

Ambient air pollution is a major health risk globally. To reduce adverse health effects on days when air pollution is high, government agencies worldwide have implemented air quality alert programmes. Despite their widespread use, little is known about whether these programmes produce any observable public-health benefits. We assessed the effectiveness of such programmes using a quasi-experimental approach.

Methods

We assembled a population-based cohort comprising all individuals who resided in the city of Toronto (Ontario, Canada) from 2003 to 2012 (about 2·6 million people). We ascertained seven health outcomes known to be affected by short-term elevation of air pollution, using provincial health administrative databases. These health outcomes were cardiovascular-related mortality, respiratory-related mortality, and hospital admissions or emergency-department visits for acute myocardial infarction, heart failure, stroke, asthma, and chronic obstructive pulmonary disease (COPD). We applied a regression discontinuity design to assess the effectiveness of an intervention (ie, the air quality alert programme). To quantify the effect of the air quality alert programme, we estimated for each outcome both the absolute rate difference and the rate ratio attributable to programme eligibility (by intention-to-treat analysis) and the alerts themselves (by two-stage regression approach), respectively.

Findings

Between Jan 1, 2003, and Dec 31, 2012, on average between three and 27 daily cardiovascular or respiratory events were reported in Toronto (depending on the outcome). Alert announcements reduced asthma-related emergency-department visits by 4·73 cases per 1 000 000 people per day (95% CI 0·55–9·38), or in relative terms by 25% (95% CI 1–47). Programme eligibility also led to 2·05 (95% CI 0·07–4·00) fewer daily emergency-department visits for asthma. We did not detect a significant reduction in any other health outcome as a result of alert announcements or programme eligibility. However, a non-significant trend was noted towards decreased asthma-related and COPD-related admissions.

Interpretation

In this population-based cohort, the air quality alert programme was related to some reductions in respiratory morbidity, but not any other health outcome examined. This finding suggests that issuing air quality alerts alone has a limited effect on public health and that implementing enforced public actions to reduce air pollution on high pollution days could be warranted. Together with accumulating evidence of substantial burden from long-term air pollution exposure, this study underscores the need for further strengthening of global efforts that can lead to long-term improvement of overall air quality.

Funding

Public Health Ontario, Canadian Institutes for Health Research.

February 5 | 2018

Evaluating street view exposure measures of visible green space for health research.

Larkin AHystad P.

J Expo Sci Environ Epidemiol. 2018 Jan 19. doi: 10.1038/s41370-018-0017-1. [Epub ahead of print]

Abstract

Urban green space, or natural environments, are associated with multiple physical and mental health outcomes. Several proposed pathways of action for these benefits (e.g., stress reduction and attention restoration) require visual perception of green space; however, existing green space exposure measures commonly used in epidemiological studies do not capture street-scale exposures. We downloaded 254 Google Street View (GSV) panorama images from Portland, Oregon and calculated percent of green in each image, called Green View Index (GVI). For these locations we also calculated satellite-based normalized difference vegetation index (NDVI), % tree cover, % green space, % street tree buffering, distance to parks, and several neighborhood socio-economic variables. Correlations between the GVI and other green space measures were low (-0.02 to 0.50), suggesting GSV-based measures captured unique information about green space exposures. We further developed a GVI:NDVI ratio, which was associated with the amount of vertical green space in an image. The GVI and GVI:NDVI ratio were weakly related to neighborhood socioeconomic status and are therefore less susceptible to confounding in health studies compared to other green space measures. GSV measures captured unique characteristics of the green space environment and offer a new approach to examine green space and health associations in epidemiological research.

January 29 | 2018

Human Health Risk Assessment for Gasoline Exhaust

Prepared by: Fuels Assessment Section Water and Air Quality Bureau Healthy Environments and Consumer Safety Branch Health Canada November 2017

http://publications.gc.ca/collections/collection_2017/sc-hc/H144-52-2017-eng.pdf

Excerpt from Executive Summary

Gasoline, or spark ignition, engines are used throughout Canada, representing 92% of on-road vehicles and 87% of off-road engines or equipment. It is reasonable to assume that exposure to gasoline engine exhaust (GE) is nearly ubiquitous, particularly for Canadians living in urban areas or in close proximity to a major roadway: it is estimated that approximately 2 million people live within 50 m of a major road in Canada. GE is a highly variable and complex mixture of particulate and gaseous pollutants, the composition of which depends on numerous factors, including fuel quality, engine and pollution control technologies, vehicle operating conditions and ambient temperature. GE is an important source of criteria air contaminants (CACs) associated with adverse effects on human health, including fine particulate matter (PM2.5), ground-level ozone (O3), nitrogen dioxide (NO2), volatile organic compounds (VOCs) and carbon monoxide (CO). In addition, GE constituents include air toxics that are recognized internationally as carcinogens, such as benzene and polycyclic aromatic hydrocarbons (PAHs).

Gasoline fuel, vehicles and engines are subject to multiple federal regulations that have successfully reduced air pollutant emissions from gasoline mobile sources, representing a major success in the management of air quality in Canada and the protection of human health. However, given the number of vehicles and engines in use, the age structure of the in-use fleets, and the vehicle kilometres travelled by Canadians, gasoline engines remain a key source of air pollution. The adverse health effects of individual pollutants in GE or produced secondarily in the atmosphere from primary GE emissions (e.g. PM2.5, O3, NO2, benzene and PAHs), are well characterized in the scientific literature and include increased risk of cardiorespiratory mortality and morbidity and of cancer, among other outcomes.

This report is a comprehensive review and analysis of the potential adverse health effects associated with gasoline fuel use in Canada. Two distinct approaches are used. Part A provides an evaluation of scientific studies that have examined the health effects associated with exposure to GE as a mixture. Studies on the health effects of individual GE constituents, such as PM2.5 and benzene, were not considered, as these substances have been extensively reviewed by Health Canada elsewhere. Part B provides a quantitative assessment of the contribution of on-road and off-road gasoline mobile source emissions to individual air pollutant concentrations in Canada and the population health impacts associated with that incremental contribution. The health impact analysis in Part B, which is based on well-established quantitative estimates of risk of adverse health impacts associated with incremental changes in air concentrations of individual pollutants, is complementary to the traditional risk assessment approach presented in Part A.