The Built Environment and Public Health

Russell P. Lopez

• Publisher: Jossey-Bass
• Year: 2011
• ISBN:
  9781118122129
• Edition: 2
• Topic: Medicina
• Subtopic: Medicina in ambito lavorativo e industriale

THE BUILT ENVIRONMENT AND PUBLIC HEALTH

The Built Environment and Public Health explores the impact on our health of the environments we build for ourselves, and how public health and urban planning can work together to build settings that promote healthy living. This comprehensive text covers origins and foundations of the built environment as a public health focus and its joint history with urban planning, transportation and land use, infrastructure and natural disasters, assessment tools, indoor air quality, water quality, food security, health disparities, mental health, social capital, and environmental justice. The Built Environment and Public Health explores such timely issues as

• Basics of the built environment and evidence for its influences
• How urban planning and public health intersect
• How infrastructure improvements can address chronic diseases and conditions
• Meeting the challenges of natural disasters
• Policies to promote walking and mass transit
• Approaches to assess and improve air quality and our water supply
• Policies that improve food security and change how Americans get their food
• How the built environment can address needs of vulnerable populations
• Evidence-based design practices for hospitals and health care facilities
• Mental health, stressors, and health care environments
• Theories and programs to improve social capital of low-income communities
• How the built environment addresses issues of health equity and environmental justice

This important textbook and resource includes chapter learning objectives, summaries, questions for discussion, and listings of key terms.

Companion Web site: www.josseybass.com/go/lopez

Part I

Background and History

iStockphoto/© Algimantas Balezentis

Chapter 1

Introduction to the Built Environment and Health

Learning Objectives

• Compare the three domains that make up the broader concept known as the environment.
• Assess whether the built environment is consistent with the defining characteristics of environmental health.
• Describe the health, equity, and sustainability framework for evaluating the built environment.
• Name some of the professions that are associated with built environment research and practice.
• Describe the processes that shape the built environment.

How does the built environment affect your health? Consider the many different ways. Your apartment, home, dorm, or other place you spend the night protects you from the cold and rain. Curbs separate pedestrians from cars, and schools and commercial buildings have fire alarms, emergency exit signs, and other safety features. For the next twenty-four hours, look around and try to identify the many ways the built environment has been modified for your protection. Were you aware of all of these features? Do you think most people know how much the built environment shapes their daily lives? We will come back to these factors of the built environment in more detail later in this book. For right now, just consider the range and variety of built factors specifically added to the environment for your health and safety.

This book is a survey of the many pathways between the built environment and health, with an emphasis on issues in the United States. The built environment refers to all the many ways humanity builds or manipulates the world around it. The health effects of the built environment occur on multiple scales, including houses, streets, neighborhoods, metropolitan areas, regions, nations, and beyond. Some impacts operate on very large geographic and temporal ranges, including international or national effects on millions of people over multiple generations. The U.S. interstate highway system, for example, transformed landscapes across the country and contributes to global climate change.1 Other effects operate at a very local level and may only affect a few individuals for relatively brief moments in time. For example, a temporary sidewalk closing due to building construction may force pedestrians to walk in the street, potentially putting them at risk from passing cars. Including large- and small-scale impacts, those transitory and permanent, the collective impact of the built environment on health may be large.2

The built environment provides the framework for how daily lives are conducted, influences health across life spans, and represents important pathways through which individuals come into contact with many health risks. Though the associations between the built environment and health have only been subject to modern epidemiological scrutiny for the past two decades, and efforts to use the power of built environment interventions to address our current health concerns are only in their infancy, there is growing evidence that some environments can promote health while others increase morbidity and mortality.3 This book provides an overview of the evidence that links the built environment with health, and it describes some of the program, policies, and projects that have been used to modify the environment to promote health.

Dimensions of the Environment

The term environment is very broad and can mean many things to different people. Even scientists from different disciplines can utilize varying conceptions of what constitutes the environment. To the geneticist, for example, the environment can be everything outside the genome including features operating on or below the cellular level that influence gene expression or modify genetic material.4 To the sociologist, however, environment might mean factors beyond what is physically existent in an individual's body and describes the interactions between and among individuals, groups, and societies.5

For the purposes of this book, the environment is divided into three broad domains: the physical, social, and built environments. The physical environment includes all the various features that are part of mainstream environmental literature: forests, prairies, watersheds, plants, animals, and so on. It also includes the factors that are of concern to classic environmental health: air and water pollutants, radiation hazards, and so forth. These exposures are well known to be associated with certain diseases and to be linked to better or poorer health. Many of these physical environment problems are discussed in this book because the likelihood of exposure to them can be influenced by the built environment. For example, factories, prominent features of the built environment, can influence the degree to which an individual who lives near these facilities may be exposed to air pollutants, and thus impact health.6 Physical environment attributes may arise from a built environment feature.

The social environment represents the many features that result from or are part of how humans interact with each other. These include the distribution of income, the role of race in society, political power, and other similar factors. There is a large body of evidence showing that the social environment can have profound impacts on health, a field that is also known as social determinants of health. For example, even though race is a social rather than a biological construct,7 how an individual's race is perceived can have important lifelong impacts on health, from the risk of infant mortality to the incidence of prostate cancer in later life.8 Race interacts with the built environment in many ways. It can influence income and wealth, which can then lead to an individual's ability to live near parks and other environmental amenities.9 It may limit access to certain neighborhoods, affecting an individual's exposure to hazardous wastes or influencing access to nutritious food.10 Thus the social environment is also included in this book.

The built environment itself consists of all the many features that have been constructed and modified by humanity. These include everything from how rooms are laid out, to the construction of homes, to the various land uses in a neighborhood, to the structure of neighborhoods and metropolitan areas, to the way regional and national geography and infrastructure interact to protect (or not protect) people from natural disasters. All of these levels of the built environment will be discussed here.

These three domains are not totally discrete, that is, there is considerable overlap between them. For example, racial residential segregation, the degree to which racial groups are concentrated in certain neighborhoods in many metropolitan areas, is both a social and a built environment factor.11 It is a social factor because race itself is a social construct, only defined in the context of the society in which an individual lives. But when individuals can only buy or rent in certain neighborhoods, and thus their access to supermarkets, pharmacies, and hospitals is constrained, then it is also a built environment factor. Furthermore, when the influence of segregation is considered in the study of the distribution of environmental hazards and amenities, it includes the physical environment as well.

Is the Built Environment Really an Environmental Factor?

For those who consider the term environment in a more traditional manner, for example, those who think of the word in the context of narrow national pollution laws, there may be concern that the built environment is not a part of the environment at all. Some may believe that the term environment should be restricted to those attributes that exclude human-made features completely, or they at least place cities and intensely developed areas at the bottom of a hierarchy that places natural areas yet untouched by human influence at the pinnacle of desirable environments; others, however, have long advocated for the inclusion of humanity when considering the natural environment. But traditionally, the field of environmental health, the branch of public health from which concerns regarding the built environment first reemerged in the 1990s, has defined its agenda by posing a series of questions that set out to include or exclude certain health risks from consideration. By applying these criteria to the health effects of the built environment, we can determine whether or not the built environment is properly considered to be part of environmental health studies. These questions include:

Does the risk occur outside the body?

The source of the problem should originate externally for it to be considered environmental. For example, even though environmental health is very concerned about environmental features that promote hypertension, high blood pressure itself is not traditionally considered to be an environmental disease and is rarely discussed in environmental literature. The proximal causes of hypertension, and its health effects, are observed internally; thus, hypertension is not an environmental health risk. In contrast, some distal factors are environmental stressors for hypertension and are within consideration here, including noise exposures, the distribution and availability of healthy food choices, the influence of the built environment on physical activity, and so on.12 Therefore, sodium consumption, a major risk factor for high blood pressure, is not often discussed in the context of environmental health, but neighborhood food environments that offer few healthy options yet have ubiquitous sources of high-sodium foods are considered here. In general, though the health consequences of the built environment are almost always internally observed, their causes lie outside the body: in a person's home, neighborhood, metropolitan area, or rural community. Thus built environmental factors are not internal to the body—the risks are external.

Is the exposure or health risk voluntary?

Generally, environmental health includes involuntary rather than voluntary risks. Smoking is considered to be voluntary (though, as will be discussed in this book, there are features of the built environment that affect the likelihood that someone will smoke), and thus it is not generally considered to be an environmental health problem. In contrast, exposure to secondhand smoke is considered to be an environmental issue, as suggested by secondhand smoke's alternative name, environmental tobacco smoke.13 Nonsmokers exposed to tobacco smoke do not cause the exposure but rather become exposed because of the actions of others.14 Considering the built environment, though, there is some individual choice regarding in what sort of environment one lives. For the most part, the broad parameters of the built environment—streets, the need to use a car to get to work, the construction of public works, and so forth—are set by society and an individual has little control over these features.15 Thus the health risks and benefits of the built environment are not voluntarily accepted or individually produced.

Is the health risk caused by a biological agent?

Though very concerned about malaria and other vector-borne diseases as well as diseases spread by contaminated water, for the most part environmental health does not address diseases caused by viruses, bacteria, and other organisms. Thus, as important an issue as it may be, HIV/AIDS is not a major subject in the environmental health literature. However, the built environment's influences on risk behaviors are considered here.16 In general, the risks outlined in this book act on individual health without the intervention of biological agents.

Taken together, built environment to health pathways tend to originate outside an individual's body and health issues associated with the built environment tend to result from involuntary exposures to nonbiological factors. Based on these criteria, the built environment may be properly considered to be part of environmental health. This does not mean that everyone will agree about this application of these guidelines, only that built environment factors are consistent with the generally accepted parameters of environmental health.

How to Evaluate the Built Environment?

A recurring theme of this book is how do we measure and assess the built environment? How can we objectively describe its features and impacts? As will be seen, there are many ways to evaluate the built environment. For the most part, this book uses epidemiological evidence whenever possible. These include peer-reviewed articles published in academic journals that use standard health research methods. Among the epidemiological tools included here are case-control studies; cohort designs; and qualitative, ecological, and multilevel analysis. The book also uses engineering reports, case studies, architectural assessments, theoretical texts, and other sources as well.

Public Perceptions and Assumptions Regarding the Built Environment

The modern study of the built environment is a fairly new field of research. Although there have been concerns that some environments were healthier than others even back in ancient times17 and the fields of urban planning and public health had common beginnings that resulted from problems posed by urbanization in the nineteenth century, the majority of research on the built environment that meets current standards of scientific validity dates back to the last two decades.18 Thus it is likely that the full range of health effects may not yet be identified and it is always possible that a connection between the built environment and health accepted today may prove to be discounted in the future when additional evidence is analyzed...