Air quality in Guanajuato

What is the current level of air pollution in Guanajuato city?

Guanajuato is a city and municipal seat of the municipality of Guanajuato in central Mexico and the capital of the state of the same name. According to a census conducted in 2020, Guanajuato had an estimated population of approximately 195,000 inhabitants.

Towards the end of the third quarter of 2021, Guanajuato was experiencing a period of “Moderate” air quality with a US AQI reading of 55. This United States Air Quality Index figure is used as a metric when comparing one city with another, anywhere in the world. It is calculated by collating the recorded levels of six of the most prolific air pollutants. These can include, both diameters of PM (PM10, PM2.5), nitrogen dioxide, sulphur dioxide, ozone and carbon monoxide. If figures are not available for all six, a level can still be calculated by using what information there is.

For Guanajuato, the only pollutant measured was that of PM2.5 which was 14 µg/m³. This figure is quoted in microns per cubic metre. This record of PM2.5 is just under one and a half times higher than the suggested level of 10 µg/m³ which is a level found to be acceptable by the World Health Organisation (WHO), although no amount of air pollution is considered as being safe.

Although this is not an excessive level of polluted air, the given advice would be to remain indoors as much as possible and close all windows and doors to prevent more dirty air from entering the rooms. Those of a sensitive disposition should avoid venturing outside if at all possible. If this is unavoidable, then a well-fitting face mask should be worn at all times. There is a downloadable app from AirVisual which is available from the app store and is suitable for most mobile devices. It will give you the level of air pollution in real-time.

Does the level of air pollution vary throughout the year in Guanajuato?

Air quality can be influenced by many variables and can therefore change quite quickly. Looking back at the figures for 2020, published by IQAir.com, it can be seen that during the months of August, September and October Guanajuato achieved the WHO target figure of being less than 10 µg/m³. The actual numbers were 9.9, 9.4 and 9.8 µg/m³, respectively. The month of November saw a “Good” air quality with a figure of 11.1 µg/m³. The remaining eight months of the year saw “Moderate” quality with readings between 12.1 and 35.4 µg/m³. The worst month of the year was April with a figure of 16.7 µg/m³.

Historically, records have been kept since 2018 when it was noted that the WHO target figure was attained. The actual reading being 9.0 µg/m³. The following year saw a decline with a “Moderate” figure of 12.8 µg/m³, but a slight improvement was noted in 2020 when that figure was 12.6 µg/m³. This figure may well have been affected by the ongoing COVID-10 pandemic when many vehicles were no longer in daily use as their drivers were not required to drive to the office every day. There were also several small factories and processing units that were closed temporarily so their emissions were no longer part of the local atmosphere.

Where does the polluted air come from in Guanajuato?

The cities of Guanajuato, Salamanca and Irapuato show, once again, high levels of sulphur dioxide concentration. The high levels of concentration of pollutants are due to the use of fuel oil in the production processes of the Salamanca Thermoelectric Power Plant and the Ingeniero Antonio M. Amor Refinery.

Air pollution in the city is caused mainly by the high concentration of population, the vehicle fleet and the emissions from industry. The main cause of the increase in PM10 particles in the air is due to open burning, bonfires, fireworks, burning grasslands, burning trees, among other factors. PM10 particles occur most frequently during the winter season, which is when the cold contains the particles mostly in the sky and they disperse more slowly.

In Guanajuato, pollution is serious, where 68 per cent of its soil is eroded, 15 thousand tons of solid waste are produced every day, it has more than 1.7 million vehicles that travel daily, most of which are more than 10 years old, which together with the grassland fires generate serious problems to the air quality, mainly in the Industrial Corridor. A 10-year-old vehicle pollutes up to 10 times more than a more recent one, but in Guanajuato a verification model is being carried out that involves other municipalities, so that model should be reviewed and people trust the program. so that you know if your vehicle is in the best condition.

What can improve the air quality in Guanajuato?

Specific actions included the removal of lead from gasoline, implementation of catalytic converters in automobiles, reduction of sulphur content in diesel fuel, closure of an oil refinery, substitution of fuel oil in industry and power plants with natural gas, reformulation of liquefied petroleum gas for cooking and heating, reinforcement of vehicle inspection and maintenance program, and implementation of “no driving day (Hoy No Circula)” rule. As a result of these measures, concentrations of criteria pollutants have been steadily decreasing over the past decade.

What are the detrimental effects on human health from the polluted air in Guanajuato?

Exposure to high levels of air pollution can cause a variety of adverse health outcomes: it increases the risk of acute respiratory infections, heart disease, stroke, and lung cancer. Both short-term and long-term exposure to air pollutants have been associated with negative health impacts.

Air pollution is a critical risk factor for noncommunicable diseases, it is estimated to be the cause of 24 per cent of all adult deaths from heart disease, 25 per cent of deaths from stroke, 43 per cent of deaths from obstructive lung disease chronic disease and 29 per cent of lung cancer deaths.

Ambient air pollution alone caused approximately 4.2 million deaths in 2016, while domestic air pollution caused by cooking food with polluting fuels and technologies caused about 3.8 million deaths in the same period. In Mexico, 18 million people use firewood for cooking which has negative consequences not only for human health, but also for the planet by reducing the area of forests.