Sprawl and Health

Leung 1998 - "Evaluation of Personal Exposure to Monoaromatic Hydrocarbons"

Leung, Pei-Ling; Harrison, Roy M
"Evaluation of Personal Exposure to Monoaromatic Hydrocarbons"
Occupational and Environmental Medicine
April 1998; v.55, n.4; pp. 249-257
On the Web
Relevance: high

The authors measured the exposure of 50 volunteers in the UK to various monoaromatic hydrocarbons (MAHs) over the course of 12 hour days. They found that urban volunteers were exposed to more MAHs than non-urban volunteers. Most of the total exposure is from the home, despite low concentrations, due to the vast amount of time spent there. Although little time is spent driving, the high concentration of MAHs in vehicles made it a noticeable contributor for office workers (5% of total exposure) 

Allen 2004 - "Estimated Hourly Personal Exposures to Ambient and Nonambient Particulate Matter Among Sensitive Populations in Seattle"

Allen, Ryan; Wallace, Lance; et al.
"Estimated Hourly Personal Exposures to Ambient and Nonambient Particulate Matter Among Sensitive Populations in Seattle"
Journal of Air and Waste Management
September 2004; v.54; n.9; pp.1197-1411
On the Web
Relevance: High

The authors measured the concentration of particulate matter in various mircoenvironments (home indoors, home outdoors, work, school, in transit, other outdoors, other indoors) and the average exposure for 38 subjects in Seattle. The subjects selected were "sensetive populations" with asthma, coronary heart disease, or advanced age. The major findings were:

• The best air was indoors at home; the worst air was at work, followed by outdoors and in transit.
• Because subjects spend so much time at home, most of their exposure (79%) occured there.
• There was a low correlation between ambient and personal exposures (0.43) compared to findings from other studies. This means that localized sources highly affect personal exposure (i.e. cooking fumes vs.general air quality)

Nasar 1995 - "The Psychological Sense of Community in the Neighborhood"

Nasar, Julian
"The Psychological Sense of Community in the Neighborhood"
Journal of the American Planning Association
Spring 1995; v61, n2; pp 178-184
Relevance: high

There is more social capital--at least as conceived as neighborhood social ties--in mixed-use (and presumably higher density) communities than in single use communities. From the abstract: This paper describes the development and testing of an 11-item Likert scale of the sense of neighborhood community, using responses from 54 residents in three suburbs in Columbus, Ohio. One test of the scale with 100 residents in single-use and mixed-use areas near one another found significantly more sense of community in the mixed-use neighborhood. More sense of community emerged among married persons and couples with children as compared to singles and childless couples.

Much of this paper is devoted to justifying its research methodologies. Of particular interest is a list of 15 questions on page 181 that researchers used to ascertain neighborhood social ties. This could be of use in future primary research on social capital.

Hawe 2000 - "Social capital and health promotion: a review"

Penelope Hawe, Alan Shiell
"Social capital and health promotion: a review"
Social Science & Medicine    
September 2000; v51, n6, pp 871-885
On the Web
Relevance: Medium-low

This is a somewhat interesting perspective on the history of social capital. Written from a social science perspective it provides a different and broader context for social capital theory than the other scientific studies reviewed here. It also treats the metaphorical and rhetorical dimensions of the language of social capital.

The authors also briefly review the scientific literature on the relationship between social capital (and income inequality) and health. While the review is not as comprehensive or detailed as other studies reviewed here, it is clearly written and pithy, making it a handy reference.

Kingham 1998 - "Assessment of Exposure to Traffic-Related Fumes During the Journey to Work"

Kingham, Simon; Meaton, Julia; et al.
"Assessment of Exposure to Traffic-Related Fumes During the Journey to Work"
Transportation Research, Part D
July 1998; v.3, n.4; pp.271-274
On the Web
Relevance: medium-low

In a pilot study, the authors measured commuter's exposure to benzene and particulates using different modes (car, bus, train, road cyclist, path cyclist) but along similar routes(?). Findings include:

• The car driver had the highest mean exposure to benzene (108.3 micrograms/m^3) a factor of at least 4 and also the highest mean exposure to particulates (7.6 absorbance), but by a much smaller margin.
• Train riders had the lowest benzene exposure (12.9) and path cyclists had the lowest particulate exposure (2.7).
• The bus was slightly better than the road bike
• The exposure ratios for the car driver to the road cyclist were 4.05 for benzene and 1.26 for particulates.
• The exposure ratios for the road cyclist to the path cyclist were 1.73 for benzene and 2.41 for particulates.

Adams 2002 - "Assessment of Road Users' Elemental Carbon Personal Exposure Levels, London, UK"

Adams, HS; Nieuwenhuijsen, MJ; Colvile, RN.
"Assessment of Road Users' Elemental Carbon Personal Exposure Levels, London, UK"
Atmospheric Environment
November 2002; v.36, n.34; pp.5335-5342
On the Web
Relevance: low

The authors measured exposure to elemental carbon (EC) a component of diesel exhaust, along various routes, using different modes, and in summer vs. winter.  They found that exposure levels were higher:

• for cars, followed by buses and bicycles (cyclists may have lower exposure because they don't get stuck in traffic and keep "away from the central road 'tunnel of pollution'.";
• along the most congested central route, perhaps due to higher traffic density and a street canyon effect;
• in winter, perhaps due to colder engines and more stable meteorological conditions.

Fruin 2004 - "Black Carbon Concentrations in California Vehicles and Estimation of In-Vehicle Diesel Exhaust Particulate Matter Exposures"

Fruin, Scott A; Winer, Arthur M; Rodes, Charles E.
"Black Carbon Concentrations in California Vehicles and Estimation of In-Vehicle Diesel Exhaust Particulate Matter Exposures"
Atmospheric Environment
August 2004; v.38, n.25; pp.4123-4133
On the Web
Relevance: low

The authors measured black carbon (BC) concentrations inside vehicles driven around LA and Sacramento. BC is typically associated with diesel emissions. The authors found that the most important predictor of in-vehicles BC concentrations was the type of vehicle followed, with diesel buses and delivery trucks that had ground-level exhaust pipes being the worst. Following a gasoline powered car did not increase BC concentrations.

The authors also estimate daily exposure to diesel particulate matter (DPM), concluding that compared to earlier models, "in-vehicle DPM exposures appear to make very significant contributions to overall DPM exposures, randing from approximately 30-55% of total DPM exposure on a statewide, population basis.  Thus the in-vehicle microenvironment may be the most important route of overall DPM exposure, though only 1.5h day-1 is spend there, on average."

Friedman 2001 - "Impact of Changes in Transportation and Commuting Behaviors During the 1996 Summer Olympic Games in Atlanta on Air Quality and Childhood Asthma"

Friedman, Michael S; Powell, Kenneth E; et al.
"Impact of Changes in Transportation and Commuting Behaviors During the 1996 Summer Olympic Games in Atlanta on Air Quality and Childhood Asthma"
Journal of the American Medical Association
February 21, 2001; vol.285, n.7; pp.897-905.
On the Web
Relevance: low

The authors compared the level of air pollution and asthma events during the Atlanta Olympics to levels just before and after. They found that ozone levels and asthma events were lower during the Oympics, likely due to changes in traffic patterns. The number of asthma acute care events decreased 41.6% in the Georgia Medicaid claims file.  Organizers increased public transportation, closed the downtown to cars, encouraged workers to change work hours, and made other adjustments. There are several caveats to this study, so we may not want to quote it alone, but it could be one building block of the case.

Adams 2001 - "Determinants of Fine Particle (PM2.5) Personal Exposure Levels in Transport Microenvironments, London, UK"

Adams, HS; Nieuwenhuijsen, MJ; Colvile, RN
"Determinants of Fine Particle (PM2.5) Personal Exposure Levels in Transport Microenvironments, London, UK"
Atmospheric Environment
September 2001 v.35, n.27; pp.4557-4566
On the Web
Relevance: medium-low

The authors measured concentrations of fine PM on fixed routes using different modes (car, bus, bicycle) in London. They found that route was a significant factor, explaining 20% of the variation, but mode was not. Wind speed explained 18% of the variation. "Personal exposure levels were reasonable correlated with urban background FSM [fixed site monitor] concentrations."

CARB 1998 - "Measuring Concentrations of Selected Air Pollutants Inside California Vehicles"

California Air Resources Board (CARB)
"Measuring Concentrations of Selected Air Pollutants Inside California Vehicles"
December 1998, Contract No. 95-339, Final Report
On the Web
Relevance: medium-low

CARB measured concentrations of various air pollutants inside vehicles as a range-finding experiment. They studied the effect of freeway conditions (rush vs. non-rush), roadway types, vehicle types, air vent settings, time of day, and roadside/ambient air quality.

CARB found that pollutant concentrations were higher:

• in the regular vs. carpool lane
• during rush hour
• when following diesel or other high-emitting vehicles

Other findings include:

• Vent settings and vehicle type did not seem to make a big difference
• "Most pollutants levels, especially the VOC's, were elevated inside and outside the vehicles relative to either the roadside or ambient station concentrations"
• "Particle concentrations were typically significantly higher outside the vehicles than inside, presumably due to losses in the vehicle ventilation systems (and other factors) - while significant differences were not observed between inside and outside levels of gas phase pollutants for the same vehicle."

CAVEAT: this was a preliminary, range-finding study, so we should look at other studies for confirmation and hard numbers.