In Brazil, thanks to a road ring, air pollution was reduced by up to 25%

São Paulo is one of the most populated cities in Latin America and the world with 11,253,000 inhabitants, according to the 2010 IBGE Census. The city is also one of the most congested; according to the signature Inrix, drivers lose approximately 86 hours a year stuck in traffic jams during peak hours.

Leer en español: Las vías periféricas no solo ayudarían al tráfico, también a la salud

The Rodoanel Mário Covas is a 177 kilometer road ring that surrounds the center of the Metropolitan Region of São Paulo and arose in response to the need to improve traffic. This road ring deviates the heavy traffic of commercial routes that cross the city every day, between Puerto Santos and the interior of Brazil.

In a study published in the Journal of the European Economic Association, researchers from the National University of Signapur (NUS) and the University of São Paulo examined the impact of the opening of the South Rodoanel on megacity traffic, air quality and public health. The opening of this section in April 2010 allowed the diversion of commercial traffic from the city, especially from Avenida dos Bandeirantes, important in the route that connects with the Port of Santos and key corridor of the interior of the city. It is estimated that since the inauguration 20 thousand heavy vehicles stopped circulating daily in the city.

Researchers report that the number of hospital admissions and deaths related to respiratory and cardiovascular problems in the vicinity of major city avenues decreased, particularly in vulnerable age groups.

Traffic congestion

The researchers examined 5100 monitored road segments and found that the effect of the measure was immediate, the traffic congestion of the city was alleviated by 20% due to the diversion of trucks. However, the decongestion was not maintained over time, since 2012 the space left by the trucks was occupied by light vehicles. This answer is not surprising in a system saturated with constantly collapsed roads as in São Paulo.

Thanks to the measure, air pollution by nitrogen oxides (NOx) in the most important corridors of the city was reduced by up to 25%.

Air quality and public health

Although the objective of the road ring was to improve traffic to the interior of São Paulo and provide an easier access route to the Port of Santos, the policy had desirable, though not voluntary, effects. One of them was the improvement of air quality by reducing the circulation of vehicles moved to diesel inside the city, which emit highly polluting particles.

Thanks to the measure, air pollution by nitrogen oxides (NOx) in the most important corridors of the city was reduced by up to 25%. These toxic gases are produced by the burning of diesel and in high concentrations are associated with respiratory problems, cardiovascular diseases and cancer. They also increase the concentration of ozone and remain in the atmosphere for a long time.

The decrease in air pollution levels remained even after the rebound in vehicular traffic due to the occupation of light cars with gasoline and ethanol from the space left by diesel trucks, because a diesel engine produces much higher emissions of oxides of nitrogen (NOx). Faced with this panorama, the researchers emphasize the critical importance of the composition of the fleet instead of the size of it considering its relationship with air pollution.

As a consequence of the initial decongestion and the subsequent change in the composition of traffic, there was a positive effect on the health of the residents of the city. The researchers report that the number of hospital admissions and deaths related to respiratory and cardiovascular problems in the vicinity of major city avenues decreased, particularly in vulnerable age groups.

The results of this research can serve as an example for other densely populated cities whose inhabitants are constantly exposed to emissions of polluting gases due to high vehicular traffic. Similar interventions could improve air quality and life in the metropolis.

Latin American Post | Alisson Cupaban
Translated from “ Las vías periféricas no solo ayudarían al tráfico, también a la salud”