Vox Civitatis the New Colonist weblog
02/07/2006: "Study Shows Poor Planning Harms Health in Several Ways"
Researchers have shown for the first time that the same pattern of unwise land use can adversely affect a wide range of health indicators, including obesity and air pollution. This comprehensive study is the first to be commissioned by a local government to assess multiple health impacts of the built environment. The study's findings were reported in the winter edition of the Journal of the American Planning Association (JAPA), the scholarly journal of the American Planning Association. The study examined the impacts the built environment could have on residents' health if it reduces opportunities for active transportation (walking or biking) and encourages more time spent in vehicles that can lead to an increase in vehicle emissions and air pollution. The authors explained that such a built environment could lead to an increased risk for several major chronic diseases, obesity, exposure to pollutants and risk of respiratory ailments.
The findings were generated from two studies conducted in King County, Washington. Use of the same walkability index in each study in the same region allowed for a strong comparison of association across multiple outcomes.
The first study conducted was the Neighborhood Quality of Life Study. It concentrated on the relationship of urban form to physical activity and obesity. The results from this study were consistent with findings of previous studies.
The second study was the King County Land Use, Transportation, Air Quality, and Health Study that assessed the effects of land use and transportation network design on travel patterns and per capita vehicle emissions, which influences air quality.
The authors found that a modest 5 percent increase in neighborhood walkability was associated with 32.1 percent more minutes per week of physically active travel, approximately a one-quarter point lower BMI (about 1.5 pounds), 6.5 percent fewer vehicle miles traveled per capita and lower vehicle emissions (5.6 fewer grams of oxides of nitrogen (NOx) and 5.5 percent fewer grams of volatile organic compounds (VOC) per capita). These compounds react in sunlight to form harmful ozone.


