Traffic-Related Air Pollution

Haneen Khreis, Mark Nieuwenhuijsen, Josias Zietsman, Tara Ramani

• Publisher: Elsevier
• Year: 2020
• Print ISBN: 9780128181225
• eBook ISBN: 9780128181232
• Topic: Technology & Engineering
• Subtopic: Environmental Management
• Index: Technology & Engineering

Traffic-Related Air Pollution synthesizes and maps TRAP and its impact on human health at the individual and population level. The book analyzes mitigating standards and regulations with a focus on cities. It provides the methods and tools for assessing and quantifying the associated road traffic emissions, air pollution, exposure and population-based health impacts, while also illuminating the mechanisms underlying health impacts through clinical and toxicological research. Real-world implications are set alongside policy options, emerging technologies and best practices. Finally, the book recommends ways to influence discourse and policy to better account for the health impacts of TRAP and its societal costs.- Overviews existing and emerging tools to assess TRAP's public health impacts- Examines TRAP's health effects at the population level- Explores the latest technologies and policies--alongside their potential effectiveness and adverse consequences--for mitigating TRAP- Guides on how methods and tools can leverage teaching, practice and policymaking to ameliorate TRAP and its effects

Chapter 1: Traffic-related air pollution: Emissions, human exposures, and health: An introduction

Haneen Khreis^a,b,c,d; Mark J. Nieuwenhuijsen^b,c,d; Josias Zietsman^a; Tara Ramani^{a a} Center for Advancing Research in Transportation Emissions, Energy, and Health (CARTEEH), Texas A&M Transportation Institute (TTI), College Station, TX, United States
^b Barcelona Institute for Global Health (ISGlobal), Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
^c Universitat Pompeu Fabra (UPF), Barcelona, Spain
^d CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain

Abstract

The research on traffic-related air pollution (TRAP) and human health has greatly evolved in the past few decades leading to improved practices and policy decision-making in many regions. Significant advances have been made including advancing the methods to assess traffic activity, vehicle emissions, air pollution, and human exposures. Furthermore, the associations between TRAP and numerous health effects have been established in epidemiology and emerging health effects are continuously being studied. The strength of the overall body of evidence is assessed and the case for biological plausibility has been strengthened through toxicological and mechanistic studies and novel high-resolution and high-throughput technologies interrogating -omics (genomics, transcriptomics, proteomics, or metabolomics). More stringent air quality guidelines have been developed and research is yet showing health risks occurring below these thresholds. Burden of disease and health impact assessments are being used more often to qualitatively asses and quantify the health burden attributable to TRAP and demonstrate the unequal distribution of that burden according to socioeconomic and sociodemographic factors. Policy options to mitigate TRAP and its adverse health effects are expanding and so are the studies quantifying the potential impacts and the cost effectiveness of a wide range of policies. The potential health impacts of emerging technologies are being discussed and best practices to achieve TRAP reductions and a multitude of goals, beyond air quality, are now documented. We have come a long way, but there are as yet critical knowledge gaps which need to be filled offering exciting research opportunities and a pathway to push and track progress toward the goal of clean air and protection of the public’s health. This book synthesizes the state-of-the-art knowledge on TRAP and human health.

Keywords

Traffic-related; Air pollution; Public health; Mortality; Morbidity; Exposure; Policy; Technology; Best practices; Environmental justice

Abbreviations

BC black carbon

BoD burden of disease

CARTEEH Center for Advancing Research in Transportation Emissions, Energy, and Health.

CO carbon monoxide

COPD chronic obstructive pulmonary disease

EC European Commission

EPA US Environmental Protection Agency

HC hydrocarbons

HIA Health Impact Assessment

NO₂ nitrogen dioxide

NO_x nitrogen oxides

O₃ ozone

PM particulate matter

PM₁₀ particulate matter with diameter < 10 μm

PM_2.5 particulate matter with diameter < 2.5 μm

ROS reactive oxygen species

SO₂ sulfur dioxide

SO₄ sulfates

TRAP traffic-related air pollution

UFP ultrafine particles

UK United Kingdom

US United States

WHO World Health Organization

Acknowledgments

Fig. 1.1 was created with funding from the Texas A & M Transportation Institute’s Center for Advancing Research in Transportation Emissions, Energy, and Health (CARTEEH), a US Department of Transportation’s University Transportation Center, College Station, TX. The grant number is 69A3551747128. More information about the Center for Advancing Research in Transportation Emissions, Energy, and Health is available at: https://www.carteeh.org/.

Introduction

Traditionally, air pollution was recognized as an issue associated with domestic heating, coal burning, and industrial emissions (Vardoulakis et al., 2003). The most recent estimates by the Global Exposure Mortality Model reported over a doubling in the number of global deaths attributable to outdoor air pollution placing them at 8.9 million deaths in 2015 (95% confidence interval: 7.5–10.3); more than the number of deaths from cigarette smoking (Burnett et al., 2018). In the present postindustrial city scape, however, outdoor air pollution in many cities of the world (e.g., high-income countries) has become dominated by emissions attributable to road traffic, including dust, tailpipe, and non-tailpipe emissions of a wide variety of pollutants harmful to human health and well-being (Anderson, Favarato, & Atkinson, 2013; European Environment Agency, E.E.A, 2007). Nowadays, traffic-related air pollution (TRAP) represents a public health crisis, the extent and magnitude of which are large and keep growing as new knowledge and quantification methods become available.

TRAP refers to ambient air pollution resulting from the use of motorized vehicles such as heavy-duty and light-duty vehicles, buses, coaches, passenger cars, and motorcycles. TRAP is often also referred to as air pollution originating from on-road mobile sources. These vehicles emit a variety of air pollutants including but not limited to black carbon (BC), elemental carbon, carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO_x), nitrogen dioxide (NO₂), particulate matter with a diameter < 2.5 μm (PM_2.5), particulate matter with a diameter < 10 μm (PM₁₀), and particles with a diameter < 0.1 μm which are referred to as ultrafine particles (UFP). These pollutants can be directly emitted through the vehicle exhaust, and are known as tailpipe emissions (Khreis, 2020). They can also be emitted through non-exhaust mechanisms such as evaporative emissions, the resuspension of dust, the wear of brakes and tires, and the abrasion of road surfaces, and are known as non-tailpipe emissions (Askariyeh et al., 2020; Khreis, 2020). The tailpipe emissions for key pollutants such as CO, NO_x, PM_2.5, and PM₁₀, and even particles number for UFP in Europe, are regulated (Khreis, 2020) and differ depending on the vehicle’s fuel type (e.g., diesel versus petrol) and age. However, non-tailpipe emissions are not entirely regulated and their relative importance is growing with the expected widespread introduction of electric vehicles (Timmers & Achten, 2016). Vehicle emissions disperse into ambient air depending on multiple factors which are highly variable such as wind speed, wind direction and atmospheric stability, local and regional terrain, and background air pollution concentrations from other sources such as industry, agricultural emissions, and coal and wood burning (Khreis, 2020). The result of this dispersion is elevated concentrations of air pollutants, through primary emissions or through the formation of secondary pollutants. Humans are then exposed to these air pollutants in ambient air, or indoors through the infiltration of outdoor air pollutants. Human exposures and their inhaled doses which reach target organs or tissues are also determined by various dynamic factors such as mobility patterns, distance from the source, age, height, physical activity, respiratory rates, and transport mode choice (Khreis, 2020). Human exposures to TRAP can elicit a wide range of adverse health effects. The full chain of events covering traffic activity, vehicle emissions, the dispersion of these emissions, human exposures, and their ultimate health impacts as described in this chapter is depicted in Fig. 1.1.

Fig. 1.1 The full chain of events linking TRAP to health impacts. Source: Center for Advancing Research in Transportation Emissions, Energy and Health (CARTEEH), available from: https://www.carteeh.org/.

The health effects of TRAP are very similar to the health effects of ambient air pollution in general. However, recent evidence shows that certain health effects, such as the onset of childhood asthma, are more strongly associated with the local (intra-urban) variation in air pollution, usually dominated by TRAP and not the region...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Contributors
• Chapter 1: Traffic-related air pollution: Emissions, human exposures, and health: An introduction
• Chapter 2: Air pollution, air quality, vehicle emissions, and environmental regulations
• Chapter 3: Traffic monitoring and modeling for energy, air quality, and health
• Chapter 4: Vehicle emissions measurement and modeling
• Chapter 5: Air pollution monitoring and modeling
• Chapter 6: Traffic-related air pollution and exposure assessment
• Chapter 7: Air pollution epidemiology
• Chapter 8: Systematic reviews and metaanalyses of air pollution epidemiological studies
• Chapter 9: Established and emerging effects of traffic-related air pollution
• Chapter 10: Evidence from toxicological and mechanistic studies
• Chapter 11: Biomarkers and omics of health effects associated with traffic-related air pollution
• Chapter 12: Qualitative health impact assessment
• Chapter 13: Quantitative health impact and burden of disease assessment of traffic-related air pollution
• Chapter 14: Impacts of traffic-related air pollution on policy- and decision-making
• Chapter 15: Policy option generation and selection
• Chapter 16: Best practices for air quality and active transportation
• Chapter 17: Air pollution mitigation through vegetation barriers and green space
• Chapter 18: Cost-effectiveness of projects and policies
• Chapter 19: The social, environmental, health, and economic impacts of low carbon transport policy: A review of the evidence
• Chapter 20: Environmental justice: Disproportionate impacts of transportation on vulnerable communities
• Chapter 21: Emerging transportation technologies and implications for traffic-related emissions, air pollution exposure, and health
• Chapter 22: Traffic-related air pollution, human exposure, and commercially available market solutions: Perspectives from the developing nation context
• Chapter 23: The state of the literature on traffic-related emissions, air pollution, human exposures, and health
• Chapter 24: How emerging technology and its integrations is advancing our understanding of urban and traffic-related air pollution
• Chapter 25: Traffic-related air pollution: Emissions, human exposures, and health—The way forward
• Index