Air quality in San Nicolas de los Garza

Is San Nicolas de los Garza a heavily polluted city right now?

San Nicolás de los Garza, sometimes just called San Nicolás, is a city and municipality in the Mexican state of Nuevo León that is part of the Monterrey metropolitan area. According to a 2005 census, the estimated population was approximately 475,000 for the city itself and over three and a half million when taking the entire metropolitan area into consideration.

Towards the end of 2021, San Nicolas de los Garza was experiencing a period of air quality that is classified as being “Unhealthy for sensitive groups” with a US AQI reading of 104. This United States Air Quality Index number is calculated using the levels of six of the most prolific air pollutants, such as nitrogen dioxide, sulphur dioxide, ozone, carbon monoxide and both sizes of particulate matter, which are PM2.5 and PM10. It can then be used as the metric when comparing air quality in other cities around the world. If data is unavailable for all 6 pollutants, a figure can still be calculated by using what figures there are. For San Nicolás the only pollutant recorded was PM2.5 with a figure of 36.7 µg/m³.

This level of PM2.5 is over three and a half times 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 quality is in this category, the given advice would be to stay indoors as much as possible closing all doors and windows to prevent the ingress of more polluted air. It is advisable to operate an air purifier if one is available, but make sure it recirculates the air and does not import more dirty air from outside. Those people who are more sensitive to poor air quality should wear a good quality face mask when venturing outside and everyone is discouraged from exercising outside until the air quality improves.

For up-to-date information about air quality, there is an app available from AirVisual.com which is downloadable for all mobile devices. This will give you the air quality in real-time.

Does the level of air pollution vary throughout the year in San Nicolás?

Air quality is very volatile as it is subject to many external influencing factors such as meteorological and atmospheric changes.

Looking back at the figures for 2020, published by IQAir.com, it can be seen that throughout the year, the air quality was classified as being “Moderate” with figures between 12.1 and 35.4 µg/m³. There were variations during the year with June providing the best quality with a reading of 18.4 µg/m³, the worst month was January with its reading of 23.9 µg/m³.

Records for air pollution were first kept in 2019 when a figure of 20.8 µg/m³ was recorded. The following year of 2020 saw a very slight improvement with a reading of 20.1 µg/m³. However, this reading may have been affected by the COVID-19 situation as many vehicles were no longer in daily use because the offices were closed, 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.

Is there a main source of air pollution in San Nicolas de los Garza?

Between the vehicle fleet, transportation, the quarries and the rest of the industry, the inhabitants of the metropolis got used to living over the decades with air pollution that grew as the population expanded. If industry is the source, they say it is the cars, and then shift the blame onto the quarries, and as long as everyone does not assume their responsibility the situation will continue to worsen. It is argued that the main source of pollution in the metropolis is that of the vehicles and public transport. It is thought that 45 per cent of the contamination is generated by these types of sources.

What can be done to improve the air quality in San Nicolas de los Garza?

A scheme is being considered where inspections of factories will be carried out at any time of the day, and on any day, seven days a week. In the event that the industrialists do not allow access, the Secretariat will be empowered to request the assistance of the public force to carry out the inspection visit, which is not contemplated in the current law either.

However, within the solutions that they do provide as a regulatory measure, they suggest investing more in energy-efficient electricity production, improving the management of domestic, industrial and municipal waste, reducing the incineration of agricultural waste, fire forestry and certain agroforestry activities.

In addition, they noted the importance of building greener and more compact cities with energy efficient buildings, providing universal access to clean and affordable fuels and technologies for cooking, heating and lighting, building safe and affordable public transport systems and networks in which consider the needs of pedestrians and cyclists.

What are the health impacts of breathing dirty air in San Nicolas de los Garza?

Scientists are finding increasing evidence of the adverse effects of six types of pollutants on human health which are both sizes of particulate matter PM2.5 and PM10, ozone (O₃), carbon monoxide (CO), sulphur dioxide (SO₂) and nitrogen dioxide (NO₂).

Scientists find it difficult to understand how pollutants affect human health. Not only because exposure to high levels is already harmful in itself. But because we are also exposed to a combination of several of them. Some, such as suspended particles smaller than 10 microns (PM10) and 2.5 microns (PM2.5) have a very varied origin. They are known to come from the burning of fuels, including transportation, energy, homes, industry, and agriculture. They are also particles so small that they can penetrate the lungs and enter the bloodstream. Several epidemiological studies have indicated that exposure to PM2.5 can affect health even at low levels. They are mainly associated with heart and lung diseases. Even short-term exposure, for hours or days, can increase the risk of hospital admission.