We find that reductions in traffic congestion generated by E-ZPass reduced the incidence of prematurity and low birth weight among mothers within 2km of a toll plaza by 6.7-9.1% and 8.5-11.3% respectively, with larger effects for African-Americans, smokers, and those very close to toll plazas. There were no immediate changes in the characteristics of mothers or in housing prices in the vicinity of toll plazas that could explain these changes, and the results are robust to many changes in specification. The results suggest that traffic congestion is a significant contributor to poor health in affected infants. Estimates of the costs of traffic congestion should account for these important health externalities.
While Ken Houghton is citing this to make a point about the harm delays in publishing cause–this is information people should know–the result itself is important.
Simply put, we have never adequately internalized the cost of automobile travel. We can argue about the extent to which road construction and gasoline manufacture and transport are subsidized, but I would like to think that “incidence of prematurity and low birth weight” are unacceptable ‘subsidies.’