242454 Co-benefits from reduced car travel in the Midwestern United States

Wednesday, November 2, 2011: 12:51 PM

Maggie L. Grabow, MS, MPH , Nelson Institute for Environmental Studies, University of Wisconsin, Madison, WI

Automobile exhaust contains fine particulate matter and precursors to ozone, posing health risks.


To quantify health and economic benefits from reducing automobile usage for short urban trips.


Using census tract-level mobile emissions estimates, we remove short automobile round-trips less than 8 kilometers from 11 midwestern metropolitan areas and simulate changes in hourly pollutant concentrations, then estimate annual health and monetary outcomes from pollution reductions using the Community Multiscale Air Quality (CMAQ) Model and EPA's Benefits Mapping Analysis Program (BenMAP). We use WHO's Health Economic Assessment Tool (HEAT) to calculate benefits of increased physical activity.


Mortality declines 1,111 deaths/year (95% CI: 856 1,346), 38% from improved air quality and 62% to improved health from bicycling. Annual average urban PM2.5 declines 0.1 g/m3, while summer O3 increases slightly in cities but declines regionally. PM2.5 and O3 changes yield extensive economic benefits, with 25% of PM2.5 and most O3 benefits being outside metropolitan areas. Economic benefits from bicycling surpass those from air quality improvements. The combined benefit from improved air quality and physical fitness is billions of dollars per year.


Significant health and economic benefits are possible if bicycling replaces short car trips. Less auto dependence also improves health in downwind rural settings.

Learning Areas:
Environmental health sciences

Learning Objectives:
Analyze and discuss the different co-benefits of substituting bicycle trips for car trips.

Keywords: Air Quality, Physical Activity

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I conducted the majority of the research for this project.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.