According to data from the World Health Organization (WHO), on a global scale it is estimated that around 90 percent of the population lives in areas with air pollution (9 out of 10 people). As a consequence, 1 death in 10 is due to this pollution. This dramatic statistic makes up the fourth most important risk factor for death on planet Earth.
The first cold fact is that in Mexico around 30 million people breathe polluted air. And it is not only a problem in its large cities, but pollution also occurs in its rural areas.
In particular, its capital, Mexico City, with its almost 9 million inhabitants, is one of the urban areas with the most air quality problems in the world. The episodes of exceeding pollution levels are repeated frequently and the measures adopted by the authorities in recent years have not achieved significant improvements.
The Government of Mexico is responsible for establishing standards for monitoring air pollutants. Through the Atmospheric Monitoring System of Mexico City (SIMAT), the Metropolitan Air Quality Index (IMECA) is made available to citizens every hour, which indicates through a scale of values and colors, air pollution levels and if the value recommended by health authorities to take care of health is exceeded.
The IMECA qualifies the air quality with respect to the pollutants that are known as criteria: sulfur dioxide, nitrogen dioxide, carbon monoxide, ozone, particles smaller than 10 and 2.5 micrometers. According to the CDMX government, this type of index does not only exist in Mexico, in other countries risk communication mechanisms have been designed with similar scales of values and colors.
PM2.5 particles can settle in the lungs and even penetrate the bloodstream, causing cerebrovascular disease, heart disease, lung cancer, chronic obstructive lung disease, asthma, or respiratory infections such as pneumonia.
In the Mexican capital, it was analyzed that a large part of air pollution is due to transportation. Vehicles are mainly responsible for poor air quality, as they produce between 53 and 56% of suspended particles, according to the Greenhouse Gas Emissions Indicators.
Despite the fact that Mexico City made a commitment to the WHO to establish standards to use cleaner vehicles, introduce low-carbon public transport and prohibit private vehicles that use diesel by 2025, current public policies to curb pollution are inefficient .
Another major factor in pollution is industry, which contributes 12.6% per year of atmospheric pollutants. The four main sources are:
- The Tolteca and Anáhuac cement plants.
- The PEMEX refinery in Azcapotzalco.
- The thermoelectric plants: Jorge Luque and Valle de México; and the PEMEX refinery, release 30% of monitored sulfur dioxide into the atmosphere.
- More than 60 paper, steel and chemical industries, among others.
It should be noted that 600 of the industries settled in the Mexican capital are highly polluting. Of these, only a quarter have anti-pollution equipment, which in many cases is insufficient or prevalent.
They also affect the pollution of the city, a large part of human activities such as agriculture. Agricultural production has profound effects on the environment as a whole. They are the main source of water pollution by nitrates, phosphates and pesticides. They are also the largest anthropogenic source of greenhouse gases, methane and nitrous oxide, and contribute greatly to other types of air and water pollution. Agricultural, forestry and fishing methods and their scope are the main causes of the world's biodiversity loss.
Another aggravating factor in the growing air pollution is the geographical conditions of the city. Because it is located in a valley surrounded by mountains, which is a kind of pot. When the intensity of the winds is reduced, the diffusion of pollutants in the atmosphere is minimal. Historically it has been a place where pollution gets trapped.
Finally, there are environmental conditions that conspire for air pollution to multiply. In the middle of the year, large fires occurred as a result of various meteorological factors such as temperatures above the average, low level of rainfall and prolonged drought, greater solar radiation and a high pressure system that prevents the dispersion of pollutants, which also cause the harmful particles stay longer in the atmosphere.