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Improving Health Through Transportation and Land-Use Policies

Policy Date: 11/10/2009
Policy Number: 20099

Transportation and land-use policies are significant factors in the built environment that affect (a) rates of injury and death caused by traffic crashes, (b) ease and safety of physical activity, (c) air quality, (d) greenhouse gas emissions, and (e) access to key community resources such as health care and healthy food. Land-use policies pertain not only to the movement of people but also to the movement of freight and goods from ships through ports and on trucks and trains, which affects communities and workers across the country. In the United States, transportation and land-use patterns have historically favored automobile travel, spawned sprawling development, and taken an unnecessary toll on human life.1 Traffic injuries and fatalities are an enormous public health and health care problem in the United States, accounting for more than 41,000 deaths annually,2 2.5 million nonfatal injuries,3 and more than $200 billion in annual expenditures.4 In 2007, there were 4,654 pedestrian and 698 bicyclist fatalities in the United States and more than 100,000 combined injuries from nonmotorized travel.5 The health costs associated with motor vehicle emissions were estimated to be $40 to $65 billion in 2000,6 and climate change is estimated to be responsible for more than 150,000 deaths per year along with devastating effects on global climate patterns.7,8 Although transportation and land-use policies affect all people, the cumulative health impacts are disproportionately borne by low-income communities and some communities of color.
National health care expenditures in the United States surpassed $2 trillion annually in 2006 [approximately 16% gross domestic product (GDP)] and are projected to constitute 17% of GDP by 2011.9 Effective transportation and land-use strategies can not only improve the health and well-being of Americans but also decrease demand on an already overextended health care system. This resolution explores 4 major health impacts of transportation and land-use policies that take some of the largest tolls on health, equity, and the economy: traffic injuries and fatalities, physical activity and nonmotorized transportation, air quality, and health equity and the disparate impact on vulnerable populations. This policy is in accordance with action steps 1 through 6, previously adopted by the American Public Health Association in American Public Health Association (APHA) policy 2004-04, Creating Policies on Land-Use and Transportation Systems that Promote Public Health.10

Traffic Injuries and Fatalities
Traffic crashes are the leading cause of death in the United States for people younger than 34.11 By 2030, traffic-related deaths will be the fifth leading cause of death worldwide.12 Native Americans are 1.5 times more likely to die from traffic crashes than other Americans 13 African Americans make up approximately 12% of the population, but they account for 20% of pedestrian deaths.14 However, traffic injuries and fatalities can be prevented through effective traffic safety policies and practices.15 Strong evidence indicates that traffic safety legislation has been effective and largely responsible for increasing people’s use of passenger and occupant safety features.16,17 Enforcement of stricter laws and public education has contributed to personal choices that favor safety (e.g., avoiding impaired driving, reducing speed, wearing helmets, and using child safety seats and safety belts).18 An estimated 301,000 lives were saved between 1970 and 2006 because of legislation associated with occupant protection, motorcycle helmets, and drinking age.19 Diversifying transportation options to accommodate safe walking, bicycling, and public transportation use can result in fewer traffic injuries compared with communities built to accommodate motor vehicles alone.20 Contrary to the widespread belief that increased bicycle and foot traffic will lead to more cyclist and pedestrian injuries, increasing the numbers of nonmotorized travelers may actually make walking and bicycling safer.21 Residents of transit-oriented communities also tend to have lower per capita traffic fatality rates.22

Physical Activity and Nonmotorized Transportation
According to the US Surgeon General, 60% of US adults do not meet recommended levels of physical activity, and 25% are completely sedentary.23 The causal link between physical activity and health is well established, with sedentary lifestyles estimated to contribute to as many as 255,000 preventable deaths per year and physical inactivity being a major contributor to the rising rates of chronic illnesses such as type II diabetes and heart disease.24 An emerging body of evidence shows that particular transportation and land-use patterns can influence people’s decision to engage in physical activity, making transportation and land-use decisions an opportunity to increase levels of physical activity.25–28 These land-use characteristics include high-density and mixed use development, good public transportation, and proximity to destinations.29,30 Characteristics such as bicycle and pedestrian facilities, good street connectivity, presence of parks and open space, and residents’ perceived safety have also been shown to enhance physical activity in some communities.31–34 Particularly in low-income communities where only 73.5% of low-income households own cars compared with 91.7% of all U.S. households, nonmotorized transportation is a good opportunity to meet daily recommended levels of physical activity.30 However, the quality of nonmotorized infrastructure is often lower in low-income and minority communities, contributing to higher pedestrian fatality rates.35 Forty percent of the lowest income transit users meet the recommended levels of physical activity solely from walking to and from transit, making public transportation an important strategy to improve activity rates among vulnerable populations.30 Because walking and bicycling remain more dangerous than motorized travel, per trip and per mile,36 improving the safety of bicyclists and pedestrians must have a high priority. Ensuring that public fears regarding violence and overall safety are fully addressed may also increase levels of physical activity.37,38

Air Quality
According to the US Environmental Protection Agency (USEPA), 35 million people in the United States are exposed to air toxins emitted from road traffic.39 Particulate matter and other pollution are often present at high concentrations along traffic-heavy roads,40 especially when a large fraction of this traffic uses diesel fuel.41 Low-income communities and some communities of color are at risk for higher levels of pollutant exposure, because their homes are more likely to be located near busy roadways.42 Several studies have documented that children going to school near major roadways have higher rates of respiratory symptoms,43 asthma diagnoses, and allergic sensitization,44,45 and children living near major roadways are more likely to suffer from asthma.48–52 Adults living or working near roadways are also more likely to suffer from asthma53–55 and other respiratory diseases,56–60 as well as atherosclerosis and other cardiovascular problems.61,62 Other health effects associated with exposure to poor air quality near roadways include cancer,63–67 adverse reproductive outcomes,68 and impaired neurocognitive performance in children.69
The transportation sector is a significant source of harmful air pollutants, including greenhouse gases. Mobile sources emit more than half of the nation’s benzene, toluene, and acetaldehyde, the air toxics of greatest public health concern, as well as approximately 91 additional air toxics that are known carcinogens or have toxicity reference concentrations in the USEPA’s main risk assessment database, the Integrated Risk Information System.70 The US transportation sector emits approximately 10% of all energy-related greenhouse gas emissions worldwide and more than one third of all transportation emissions worldwide. Over the next 50 years, greenhouse gas emission from the US transportation sector is poised to grow another 80% beyond current levels.71

Health Equity and Disparate Impact on Vulnerable Populations
In addition to disparities in the incidence of traffic injuries and deaths, limited access to opportunities for physical activity, and exposure to poor air quality, barriers to necessary community resources have disproportionately contributed to poor health among particular populations in the United States, including low-income communities, communities of color, people with disabilities, children, and older adults.72 Nearly one third of the US population—including children, older adults, people with disabilities, low-income people, women, and rural residents—are transportation disadvantaged (e.g., they are unable to transport themselves or purchase transportation).73 Low-income households can spend up to 40% of their income on transportation expenses, further perpetuating the gap in economic disparities and isolation from essential opportunities and resources.74–78 Executive Order 12898, Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations, brought federal attention to the environmental conditions that have had disproportionately adverse health effects on low-income and minority communities,79 yet there have been no equivalent efforts to address inequities perpetuated by the built environment.
Therefore APHA urges public health and social justice practitioners, advocates, researchers, and philanthropists to advocate and support advancing transportation and land-use legislation that will ensure the following goals—
1. Federal transportation policy must prioritize health, equity, and safety for all travelers. Roadways should be safe and accessible for all travelers rather than being designed exclusively for motorized travelers.
a. A greater share of federal, state, and local transportation dollars should be invested in safe infrastructure for walking, bicycling, and public transportation (including transit operating funds).
b. All new construction and redevelopment of roadways should apply the Complete Streets model to make roadways safe for all users. Complete streets ensures that roadways are designed and operated with all users in mind, including bicyclists, public transportation vehicles and riders, and pedestrians of all ages and abilities.80
c. Federal, state, and local policy should create incentives for investing in underserved communities, particularly those with existing infrastructure to support nonmotorized travel- and transit-oriented development.
d. Roadways should be designed to have good visibility, have traffic-calming features, and create greater distances and barriers between moving traffic and nonmotorized travelers (i.e., pedestrians and bicyclists).
e. Community residents, public health, labor unions, transportation system employees, social justice, and other diverse stakeholders should be engaged in transportation policy development and planning.
2. Transportation policy and subsequent implementation must prioritize using cleaner energy sources and reducing harmful emissions, including greenhouse gases.
a. Reducing the transportation sector’s contributions to global climate change should be prioritized at the federal, state, and local level.
b. Environmental justice goals to reduce the disparate exposure to harmful emissions from mobile sources should be honored and advanced in transportation and land-use activities.
c. Reducing adverse health impacts of goods movement and freight transport on low-income, minority communities and workers should be a priority in transportation and land-use policymaking.
3. Community development and redevelopment activities should preserve historic, environmental, agricultural, and aesthetic resources.
4. State departments of transportation and local agencies should partner with community groups to conduct Health Impact Assessments for major transportation and land-use activities.
a. All agencies that make decisions that affect health should be held accountable and be responsible for these health outcomes.
b. Public health should work with transportation and city planners to identify the health indicators and performance measures by which to evaluate such activities.
5. State and local transportation and land-use decisions should promote equity by—
a. Improving transportation linkages and options between housing, employment hubs, health care facilities, healthy food retailers, and schools, particularly in low-income communities and communities of color.
b. Encouraging high-density, mixed-use, and transit-oriented development with affordable housing and transit options in these developments.
c. Building roadways to accommodate safe nonmotorized travel of people with disabilities and older adults.
d. Prioritizing local and regional food transportation networks and infrastructure over long-distance ones.

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