Two out of every three persons in Chiapas lived under the poverty line in 2022, making it the federal entity with the largest share of poor population in Mexico. On average, about 36 percent of the Mexican population was living in poverty that year.

A dataset listing New Mexico cities by population for 2024.

Ajaplan was the most polluted city in Mexico in 2024, based on fine air particulate matter concentration (PM2.5). Throughout the year, the city had an average particulate matter concentration of 24.3 micrograms per cubic meter. The average particulate matter pollution in the national capital Mexico City stood at 19.5 micrograms per cubic meter that year. How bad is fine air pollution in Mexico? Fine air particulate pollution (PM2.5) refers to particles with a diameter smaller than 2.5 micrometers. Due to their small size, once inhaled they can penetrate body tissue, and trigger respiratory issues such as asthma and allergies, in addition to being associated with an increase in mortality from cardiovascular and respiratory diseases. The World Health Organization's air quality standards recommend a maximum annual average concentration of 10 µg/m³. Nevertheless, Mexico's PM2.5 levels in 2024 averaged over 17 µg/m³. This positioned Mexico in 55th place amongst the countries with the highest PM2.5 concentration that year, far below Chad, which ranked first in the list with pollution levels reaching over 90 µg/m³. Mexico also had some of the cities with the highest air pollution across Latin America, together with Chile and Peru. Where are the world’s most polluted cities? Despite pollution levels above those recommended by the World Health Organization, Mexico City didn’t even make it to the top 25 most polluted capital cities in 2024. That year, the ranking was topped by Indian capital New Delhi, with an average PM2.5 concentration of nearly 108.3 µg/m³. In fact, the majority of the most air polluted cities worldwide in 2024 were located in India, with the average PM2.5 concentration reaching as high as 128.2 µg/m³. Pakistan also had some of the world’s most polluted cities.

In 2025, approximately 23 million people lived in the São Paulo metropolitan area, making it the biggest in Latin America and the Caribbean and the sixth most populated in the world. The homonymous state of São Paulo was also the most populous federal entity in the country. The second place for the region was Mexico City with 22.75 million inhabitants. Brazil's cities Brazil is home to two large metropolises, only counting the population within the city limits, São Paulo had approximately 11.45 million inhabitants, and Rio de Janeiro around 6.21 million inhabitants. It also contains a number of smaller, but well known cities such as Brasília, Salvador, Belo Horizonte and many others, which report between 2 and 3 million inhabitants each. As a result, the country's population is primarily urban, with nearly 88 percent of inhabitants living in cities. Mexico City Mexico City's metropolitan area ranks sevenths in the ranking of most populated cities in the world. Founded over the Aztec city of Tenochtitlan in 1521 after the Spanish conquest as the capital of the Viceroyalty of New Spain, the city still stands as one of the most important in Latin America. Nevertheless, the preeminent economic, political, and cultural position of Mexico City has not prevented the metropolis from suffering the problems affecting the rest of the country, namely, inequality and violence. Only in 2023, the city registered a crime incidence of 52,723 reported cases for every 100,000 inhabitants and around 24 percent of the population lived under the poverty line.