The 5 Most Polluted Cities With the Worst Air Quality in Latin America

One of the most visible and worrying consequences that the environmental crisis has brought with it is air pollution, a problem that is accentuated in cities far from rural areas and where air quality worsens and pollution increases, putting the environment of its inhabitants at risk. This issue is very harmful to human health. According to WHO data, each year, about 10 million people die from the short and medium-term effects of inhaling toxins due to air pollution. In addition to health, we find ourselves with a concern that reflects social injustice, since the most impoverished sectors and those in the process of industrialization are the most affected.

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To measure air quality, the IQA (Air Quality Index) is used, which identifies the level of purity or contamination of a specific geographical area on a daily basis. Air pollutants are identified in two types: first are gases, among which are carbon monoxide, nitrogen dioxide, and sulfur dioxide, among others. In second place are suspended particles (PM2.5 and PM10), which are considered the most dangerous because of the ease they have to enter the respiratory tract, causing multiple respiratory problems and even cardiac arrest. The index is divided into the following indicators: Good (between 0 and 50 points), Moderate (between 51 and 100), Harmful for sensitive groups (between 101 and 150), Harmful (between 151 and 200), Very harmful (between 201 and 300) and Dangerous (with more than 301 points).

Although Latin America is not one of the regions with the highest rates of poor air quality, there are several cities that reach high levels. These are the 5 with the worst air quality according to the World Air Quality Index and IQAir.

Mexico City, Mexico

The capital of Mexico has occupied first place in the ranking of worst air quality in the region for many years now, while in the world ranking it is in the 40th position. It has a score of 81 and according to IQAir "the PM2.5 concentration in Mexico City is currently 5.3 times higher than the WHO annual air quality guideline value”. It is estimated that air pollution causes the death of between 8,000 and 14,000 inhabitants of Mexico City annually, but the authorities seem to turn a blind eye to these figures, since within the IQA they are at a Moderate level.

Lima, Peru

The city of Lima ranks second on the list in the regional ranking, and in the world ranking it ranks number 53 with an IQA of 61 points (Moderate). Despite ranking first in Latin America 2 years ago, 2022 seemed to be a good year for air quality, but last December the city climbed the ranking due to a 60% increase in air pollution, leaving in second place. IQAir data estimates that "the PM2.5 concentration in Lima is currently 3.4 times higher than the WHO annual air quality guideline value."

Bogota, Colombia

Bogota recently entered an environmental alert due to the rise in air pollution levels. As expected, the poorest sectors of the city are the most affected so far. In the regional ranking, Bogotá occupies third place, while in the world ranking it is in number 67 with an IQA of 51 points (Moderate). "The concentration of PM2.5 in Bogotá is currently 2.5 times higher than the WHO annual air quality guide value," reports IQAir. It is estimated that air pollution in Bogotá causes 8,000 premature deaths a year and is responsible for 68 million symptoms and illnesses.

Santiago de Chile, Chile

The capital of the Chilean country occupies fourth place in the regional ranking and number 74 in the world ranking with an ICA of 37 points, so it is in the Good level. Despite this, IQAir estimates that "the PM2.5 concentration in Santiago de Chile is currently 1.8 times higher than the WHO annual air quality guideline value." Thanks to this, the Chilean government considers this as the biggest environmental problem that the city is currently going through.

São Paulo, Brazil

In the last position of this ranking we find this metropolis of Brazil, which in the world index is in position number 88 with an IQA of 25 points. Just as Santiago de Chile enters the Good level, in turn, IQAir estimates that "the concentration of PM2.5 in São Paulo is currently 1.2 times higher than the WHO annual air quality guide value." In this city, inequalities are particularly clear, since this index mostly affects impoverished sectors and those that are in the process of industrialization.