Air quality in Cuajimalpa de Morelos

What is the current level of air pollution in Cuajimalpa de Morelos?

Cuajimalpa de Morelos or more commonly known simply as Cuajimalpa) is one of the 16 boroughs of Mexico City. It is situated on the west side of the city in the Sierra de las Cruces mountains which separate Mexico City from the State of Mexico. According to a census conducted in 2011 Cuajimalpa had an estimated population of approximately 186,500 people.

At the beginning of 2022, Cuajimalpa was going through a period of “Moderate” air quality with a US AQI reading of 58. This United States Air Quality Index number is an internationally used set of metrics supported by the World Health Organisation (WHO) and is used to compare the air quality in different cities throughout the world using comparable standards. It is calculated by using the levels of the six most commonly found pollutants such as nitrogen dioxide, sulphur dioxide, ozone, carbon monoxide and both sizes of particulate matter, which are PM2.5 and PM10. If all six figures are not always available in which case, a level is calculated by using what data there is. In this city, there were three main pollutants measured which were; PM2.5 - 13 µg/m³, PM10 - 35 µg/m³ and ozone (O₃) - 136 µg/m³.

This level of PM2.5 is just over the recommended safe level of 10 µg/m³ as suggested by the World Health Organisation (WHO) as being an acceptable level. Although no amount of air pollution is considered to be safe.

When air pollution is classified as being “Moderate” the advice that is offered would be to remain indoors as much as possible, closing doors and windows to prevent the ingress of more polluted air. Those who are more sensitive to poor quality air should avoid venturing outside until the situation improves. If this is unavoidable, then a high-quality face mask should be worn at all times. All types of outdoor exercise should be avoided until the air quality gets better. There is a downloadable app from AirVisual.com which is suitable for all operating systems and gives the latest information regarding air quality in real-time.

Does the level of air pollution vary much throughout the year in Cuajimalpa?

Air quality can be affected by many things, therefore it can and does change rapidly depending on the local conditions. Looking back at the 2020 figures published by IQAir.com, it can be seen that the cleanest month was August when a figure of 11.8 µg/m³ was recorded. The records for December are not currently available, but the readings for the rest of the year placed the air quality as “Moderate” with figures between 12.1 and 35.4 µg/m³. Out of these months, the dirtiest was November with a reading of 21.8 µg/m³. There were no records regarding air pollution held before 2020 when the figure was noted to be 15.6 µg/m³.

This figure would have been affected by the COVID-19 pandemic as many vehicles were no longer in daily use because the offices were closed and the staff encouraged to work from home, in an attempt to halt the spread of the virus. Many factories and non-essential production units were also required to close which removed their emissions from the atmosphere, albeit on a temporary basis. Worldwide, cities reported a much better quality of air due to the general lack of traffic pollution in city centres due to the pandemic.

What is the main source of polluted air in Cuajimalpa?

In the Valley of Mexico, the problem of air pollution is complex; it occurs due to the combination of multiple causes, and there are no single measures to solve it. Among other factors, its geographical location plays a determining role in air quality, as it is located in a closed basin, at an average altitude of 2,240 metres above sea level, surrounded by a mountain range. These natural conditions hinder the circulation of the wind and the dispersion of pollutants.

The source that contributes the most to contamination in the ZMVM is transportation; private vehicles generate most of the ozone precursors and are the second source of fine particle emissions, only after heavy diesel transport. In the Valley of Mexico there is a fleet of close to 5 million vehicles, which has grown in the last decade at an average annual rate of 3.8 per cent. This growth is explained, among other reasons, by the irrational expansion of the urban sprawl, an insufficient and deficient public transport system, and a mobility model that privileges and subsidizes private transport. The growing vehicular congestion is a factor that weighs more and more in the poor air quality of the Valley of Mexico.

What can be done to improve air quality in Cuajimalpa?

The mobility and air quality crises that occur in the Metropolitan Zone of the Valley of Mexico (ZMVM) require structural changes and the implementation of very drastic measures, even if they are not very popular among the population. These measures should be aimed at favouring public transport and significantly restricting the use of private cars, and should be commensurate with the environmental and public health cost that pollution and congestion have for society.

Added to the growing congestion, the average age of the fleet exceeds twelve years old. This is relevant since, given the fast pace of technological advances, the most recent model vehicles that have state-of-the-art equipment and controls generate fewer and fewer emissions. A vehicle over 20 years old can pollute up to 20 times more than one with the latest technology, regardless of maintenance.

What are the detrimental effects of breathing polluted air?

Breathing dirty air affects more than just the lungs and causes more than premature deaths. Air pollution affects almost every organ in the body. A recent study shows that air pollution contributes to everything from diabetes and dementia to fertility problems and childhood leukaemia.

Dirty air contains invisible material. Inhalation of soot or smoke containing particulate matter, often referred to by its size in micrometres, PM10, PM2.5 and PM1, blackens the lungs, causes respiratory and heart problems, and diseases such as asthma and cancer. Some PM10 is visible as a cloud, and like PM2.5 it affects visibility by scattering and absorbing light, but you need a microscope to see PM2.5 and an electron microscope to detect ultrafine particles. The smaller the particle, the deeper it can get into the lungs, along with the chemicals it's made of. This type of air pollution arises from the incomplete combustion of wood and plants, as well as fossil fuel, dust, and combinations of other pollutants from various sources.