Air Pollution in Mexico City

The papers Quantification of Local and Global Benefits from Air Pollution Control in Mexico City, Improving Air Quality in Megacities: Mexico City Case Study, and Air Quality Management in Mexico all looked into the issue of air pollution in the Mexico City Metropolitan Area, which increased its population 6-fold from 1950 to 2000, and presently is the largest urban agglomeration in the Western Hemisphere with population of more than 20 million While population affects many burgeoning cities in developing cities, it is especially problematic for Mexico City, which consumes more than 40 million liters of fuel daily, due to the surrounding topography, as mountains and frequent thermal inversions help to trap pollutants within the Valley of Mexico, which the capital sits. Since the mid-1980s, the government and citizens have recognized the serious concern of pollution, and regulations implemented in the 90s have helped to reduce the concentrations of various pollutants.

Currently transportation is the major source of pollution in the city, and one of the problems is that high-occupancy modes of transit have been declining as minibuses have gained popularity for their superior service and convenience, while existing formal high-occupancy systems, including the Metro, have not adequately adapted to the growing population trends. Antiquated fleet also contributes significantly to pollution, as the concentration of economic activities bring in much freight traffic. Regulation efforts have been put in to mitigate pollution. Vehicle inspection and maintenance programs, including no-driving days, began to be enforced, limiting the use of cars by one weekday starting in 1989. The policy has been remodeled to assign the ban depending on the vehicle’s emission levels. The country has also issued air quality standards comparable to those in United States. Natural gas began to replace fuel oil, and fuel quality has also been improved to reduce sulfur content and introduce unleaded gasoline. Furthermore, a low-interest loans to substitute old taxis have been implemented to improve fuel efficiency.

Despite the progresses, there are still potential pollution-mitigating projects with promising cost-benefit analysis from the standpoint of capital investment costs versus the decreased cost of health deteriorations. The project includes taxi fleet renovation, Metro expansion, hybrid bus introduction, liquid petroleum gas (LPG) leak prevention, and electricity cogeneration. The study finds that if all were implemented, the measures could save 100 lives, over 500,000 cases of minor restricted activity days (MRAD), and amount to $150 million (US) of local benefits per year. In particular, fuel savings would offset the cost of investment costs of taxi renovation, making this a particularly attractive economic investment. On the other hand, preventing LPG leaks would produce the greatest health benefit, compared to its size of investment costs, making this a high priority.

Sources:

• Instituto Nacional de Ecología: “Quantification of Local and Global Benefits from Air Pollution Control in Mexico City”
• L. Molina and M. Molina: “Improving Air Quality in Megacities: Mexico City Case Study”
• Adrián Fernández-Bremauntz: “Air Quality Management in Mexico”