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Comprehensive policies to improve Mexico City´s Metropolitan Area´s air quality

Comprehensive policies to improve Mexico City´s Metropolitan Area´s air quality
“A day without a car” Program

Mario Molina Center, 2014

Public health care should be a priority for both public policies implemented by the government and the daily actions we undertake as citizens. Poor air quality has adverse health effects, resulting in high impact economic and social problems. The proximity to vehicle emissions is a latent risk factor and it is imperative to have a comprehensive scheme at a metropolitan level that includes responsible measures of control and the optimization of public transportation and vehicular control.

Mexico City’s Metropolitan Area (MCMA) is the most polluted area in the country in terms of ozone and fourth in terms of PM10 suspended particles. Exposure to air pollution is, according to the World Health Organization (WHO), the main environmental risk factor in the world, especially affecting the elderly, children, people of lower socioeconomic strata and athletes. In Mexico, premature deaths associated with air pollution increased from 17,000 in 2005 to over 21,000 in 2010. In the case of suspended particles when they enter the lungs they can reach the bloodstream, causing heart problems, asthma and lower respiratory tract infections.

Also, children population is greatly affected, since long-term exposure to small particulate matter shows a clear relationship with deficits in lung growth in school age kids.

Air pollution derives from many different sources; nevertheless, the transportation sector is one of the largest emitters of pollutants, especially in terms of small particles, and volatile organic compounds (VOCs) and nitrogen oxides (NOx), which are precursors to ozone formation. This becomes more important because the contribution of this sector maintains an increasing trend; in only 22 years (1990 to 2012) vehicles in MCMA increased from less than three million to over five million. MCMA has experienced in the last twenty years, a significant improvement in air quality. However, the levels of ozone and particulates exceed national and international standards for air quality; for more than one hundred days during 2013 the inhabitants of MCMA were exposed to levels above the daily standards for these pollutants.

Given the apparent involvement of mobile source emissions, government measures have been implemented to improve air quality in MCMA. Recently two of these were announced: 1) the approval of vehicle emission inspection, in which vehicles from entities that make-up the Megalopolis will have the same standards; and 2) updating the No Drive Day program (NDD), whose main objective is to reduce pollution by the renewal of the vehicle fleet and avoid the use of vehicles that do not have emission control systems.

Updating the NDD program by Mexico City’s Government and the State of Mexico is due to the urgent need to address this growing threat in MCMA, as well as to protect more than 20 million people who inhabit the area. However, the implementation of this program in isolation does not solve the problem of air pollution; it is one of multiple necessary measures within a comprehensive strategy to ensure the welfare and health of the population.

The NDD has evolved over the years and has been optimized in order to achieve its main objective: reduce air pollution. The survey conducted by the Mario Molina Center (MMC) in 2013 indicates that, before vehicle restrictions, 64 percent of surveyed households decided to use public transportation, with only 5 percent who decided to buy an additional car. However, this effect is counteracted by renewal of the fleet, since in MCMA the fleet is, on average, four years more modern than in comparable cities like Monterrey and Guadalajara.

The most polluting vehicle fleet is cars over 20 years old, since they do not have catalytic converters, basic instruments to reduce pollution.

Pollution represents a high cost to public health, but this is not the only consequence generated by vehicle use and the emissions generated; there are other externalities that negatively impact society. The number of cars in MCMA also affects congestion and this has an impact on commuting time, which on average are greater than one hour per user.

In this sense, the use of public transportation which is used by about 75 percent of the population, becomes crucial to ensure public health. Undoubtedly, it is imperative to improve the efficiency, quality and supply of this mode of transportation in MCMA to decrease congestion and reduce emissions. More than two thirds of the 22 million daily trips are made by public transportation and 65 per cent of users think that the quality of service is lousy or bad.
We emphasize that poor air quality represents a severe risk to the entire population’s health. The danger of emissions from the transportation sector on human health is not obvious to the naked eye; however, in the same way that society would not allow a vehicle without brakes to circulate through the city, it is necessary to prevent the circulation of polluting vehicles that equally represent a latent and growing risk for all.

Reducing emissions and maintaining levels set by national and international standards and recommendations will only be possible if multiple measures within a comprehensive scheme in the Megalopolis are performed. It is for this reason that the NDD program can not operate in isolation and must be applied jointly with initiatives like the expansion and improvement of public transportation, with policies that ensure personal mobility, with the improvement of fuel quality, with a Megalopolis’ joint plan oriented towards transportation, and finally with a compact and sustainable urban development that favors pedestrians and clean transportation.


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