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) 

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.

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."

Rank 2001 - "Differences in Cyclists and Car Drivers Exposure to Air Pollution from Traffic in the City of Copenhagen"

Rank, Jette; Folke, Jens; Jespersen, Per Homann
"Differences in Cyclists and Car Drivers Exposure to Air Pollution from Traffic in the City of Copenhagen"
The Science of the Total Environment
2001; v.279; pp.131-136.
On the Web
Relevance: medium-high

The authors equipt two cyclists and two car drivers with air samplers for 4 hours at a time on 2 days. They found "The concentrations of particles and BTEX in the cabin of the cars were 2-4 times greater than in the cyclists' breathing zone, the greatest difference being for BTEX. Therefore, even after taking the increased respiration rate of cyclists into consideration, car drivers seem tot be more exposed to airborne pollution than cyclists.

Car/bicycle ratio

• Benzene: 2.8
• Toluene: 3.4
• Thylbenzene and Xylenes: 3.7
• Hydrocarbons: 3.7
• Particles (total dust):1.7.

ICTA 2000 - “In-Car Air Pollution: The Hidden Threat to Automobile Drivers"

International Center for Technology Assessment,
“In-Car Air Pollution: The Hidden Threat to Automobile Drivers"
Report No. 4, An Assessment of the Air Quality Inside Automobile Passenger Compartments
Washington, DC: July 2000
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Relevance: high

This report reviews 23 studies from between 1982 and 1998 covering the main pollutants inside cars: particulate matter, volatile organic compounds, carbon monoxide, nitrogen oxides, and ozone.  For all exhaust pollutants except CO and the largest PM, concentrations are typically higher inside cars in heavy traffic than elsewhere.

Kim 2001 - “Concentrations and Sources of VOCs in Urban Domestic and Public Microenvironments”

Kim, Young Min; Harrad, Stuart; Harrison, Roy M.
“Concentrations and Sources of VOCs in Urban Domestic and Public Microenvironments”
Environmental Science and Technology
March 15, 2001; v.35, n.6; pp.997-1004
On the Web
Relevance: high

Concentrations of volatile organic compounds (VOCs) were measured in a wide range of urban microenvironments (including homes, offices, shops, roadsides, buses, trains, and cars) in Birmingham, UK.  Of transportation microenvironments, cars had the highest mean concentrations of most of the VOCs measured; however the automobiles in the study were over 10 years old and smoking occurred in 6 of them during sampling.

Kim 2002 - “Levels and Sources of Personal Inhalation Exposure to Volatile Organic Compounds”

Kim, Young Min; Harrad, Stuart; Harrison, Roy M.
“Levels and Sources of Personal Inhalation Exposure to Volatile Organic Compounds” Environmental Science and Technology
December 15, 2002; v.36,n.24; pp.5405-5410
On the Web
Relevance: medium

Personal exposures to VOCs of 12 urban dwellers (Birmingham, UK) were measured over 5-10 days.  Exposure in the home contributed 50-80% of overall individual exposure to 2 main VOCs, mostly due to the large amount of time spent at home.  Smoking, vehicle use, and heating also contributed noticeably to personal exposure to VOCs.

Pucher 2003 - “Promoting Safe Walking and Cycling to Improve Public Health: Lessons from The Netherlands and Germany”

Pucher, John; Dijkstra, Lewis.
“Promoting Safe Walking and Cycling to Improve Public Health: Lessons from The Netherlands and Germany.”
American Journal of Public Health
September 2003; v.93, n.9; pp.1509-1516
On the Web
Relevance: high

Pucher and Dijkstra used data from national travel and crash surveys to compute fatality trends fatality and injury rates for pedestrians and cyclists in The Netherlands, Germany, and the United States.  The authors found that Americans walked/biked far less than do Dutch and Germans but were much more likely to be killed or injured than were Dutch and German pedestrians and cyclists, both on a per-trip and per-kilometer basis.  Causes include urban design and traffic regulations.

Retting 2003 - “A Review of Evidence-Based Traffic Engineering Measures Designed to Reduce Pedestrian-Motor Vehicle Crashes”

Retting, Richard A.; Ferguson, Susan A.; McCartt, Ann T.
“A Review of Evidence-Based Traffic Engineering Measures Designed to Reduce Pedestrian-Motor Vehicle Crashes”
American Journal of Public Health
September 2003; v.93, n.9.; pp. 1456-1463.
On the Web
Relevance: low

The authors reviewed studies on engineering measures used to reduce the risk of pedestrian injuries.  These measures were classified into speed control, separation of pedestrians from vehicles (in time and space), and increased visibility of pedestrians. Highly effective measures include:

• single-lane roundabouts,
• sidewalks,
• exclusive pedestrian signal phasing that stops all traffic while pedestrians cross all ways,
• pedestrian refuge islands, and,
• increased intensity of roadway lighting