Air quality in Salamanca

What is the current level of air pollution in Salamanca?

Salamanca is a city in the Mexican state of Guanajuato. According to a census conducted in 2020, Salamanca had an estimated population of 275,000 people. The petrochemical industry is the primary one in the city, giving rise to numerous companies and bus transport services available for employees. The strategy was to boost the creation and development of the so-called "industrial corridor" of the Bajio.

At the beginning of 2022, Salamanca was experiencing a period of “Moderate” air quality with a US AQI reading of 59. 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 Salamanca, all six major pollutants were measured. They were as follows; PM2.5 - 16 µg/m³, PM10 - 24 µg/m³, ozone (O₃) - 0.1 µg/m³, nitrogen dioxide (NO₂) - 0 µg/m³, sulphur dioxide (SO₂) - 0 µg/m³ and carbon monoxide (CO) - 2015.2 µg/m³.

This level of PM2.5 is just over one 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 pollution is classified as being “Moderate” the given advice 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 it improves. If this is unavoidable, then a good quality face mask should be worn at all times. All types of outdoor exercise should be avoided until the air quality improves. 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 Salamanca?

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 for the entire twelve months, the air quality was classified as “Moderate” with figures between 12.1 and 35.4 µg/m³. The cleanest month was September with a figure of 13.6 µg/m³, the dirtiest was April at 21.9 µg/m³.

Records for air quality were first kept in 2017 when a figure of 25.1 µg/m³ was recorded. There was an improvement the following year with a reading of 20.9 µg/m³, and this repeated itself in 2019. In 2020, the figure was recorded as 18.0 µg/m³ but this lower figure was almost expected because it 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 air pollution in Salamanca?

Built 70 years ago, the "engineer Antonio M. Amor" refinery in Salamanca, Guanajuato, is one of the two main generators of pollutants in the state and one of the critical points of sulphur dioxide emissions in the world, according to the classification of the worst global sources of contamination by this pollutant, made by Greenpeace, based on data from NASA.

The oil and petrochemical industry in the state generates 91.17% of the amount of sulphur dioxide that is emitted into the air in the state; 38.77 per cent of PM10 particles; 29.28 per cent of PM2.5 particles; 16.46 per cent carbon monoxide; 40.30 per cent nitrogen oxides; and 45.40 per cent volatile organic compounds.

What can be done to improve air quality in Salamanca?

Specific actions included the removal of lead from gasoline, implementation of catalytic converters in automobiles, reduction of sulphur content in diesel fuel, 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.

It has also implemented climate change strategic programs with clear and specific targets, including green energy (e.g., solar panels), energy efficiency programs for public buildings, and sustainable development of natural resources and biodiversity.

With health and environmental policies aimed at reducing air pollution, the city is seeing cleaner air even as it continues to expand and grow. The densely populated urban area is an ideal place to put clean air policies to work — and help save thousands of lives.

What are the detrimental effects of breathing in polluted air?

Many residents experience some form of air pollution-related symptoms, such as watery eyes, coughing, or wheezing. Even for healthy people, polluted air can cause irritation or breathing difficulties during exercise or outdoor activities. Your actual risk depends on your current health status, the type and concentration of the contaminant, and the length of time you are exposed to contaminated air.

People who are most likely to experience serious health problems from air pollution are:

• People with heart or lung disease.
• People with respiratory problems such as asthma or emphysema.
• Pregnant women.
• People working outdoors.
• Children under the age of 14, whose lungs are still developing.
• Elderly residents whose immune systems are weaker.
• Athletes vigorously exercising outdoors.

Prolonged exposure to polluted air can have permanent health effects such as accelerated ageing of the lungs and loss of lung capacity leading to a lower lung function. Development of diseases such as asthma, bronchitis, emphysema, and possibly cancer thus leading to a possible shortening of life.