Air quality in Yazd

Is Yazd a very polluted city now?

Yazd is also known as Yezd, is the capital of Yazd Province, Iran. It is located 270 kilometres to the south of Estefan. According to a census conducted in 2011, Yazd had an estimated population of approximately 529,673 which ranked it as the 15^th largest city in Iran. Since 2017, the historical city of Yazd is recognized as a World Heritage Site by UNESCO.

In September 2021, Yazd was experiencing a period of “Unhealthy” air quality with a US AQI reading of 152. This United States Air Quality Index figure is calculated by collating the recorded levels of six of the most prolific air pollutants. These may 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. It can then be used as a metric when comparing one city with another, anywhere in the world. For Yazd, there were three recorded figures for PM2.5 - 57.4 µg/m³, PM10 - 89.7 µg/m³ and sulphur dioxide (SO₂) - 29.3 µg/m³. The level of PM2.5 is currently almost six times higher than the target figure of 10 µg/m³, as recommended by the World Health Organisation (WHO).

With the level of air pollution as high as this, the given advice would be to stay indoors as much as possible and close all doors and windows to prevent more dirty air entering the rooms. The use of an air purifier would be advantageous but make sure the settings are for recirculated air so that it is not sucking in more air from outside. Those of a sensitive disposition should avoid venturing outside until the air quality improves. If this is unavoidable, then a good quality mask should be worn at all times. There is an app that is available for download from AirVisual which will give you the real air quality in real-time.

Does the level of air quality in Yazd vary throughout the year?

Air quality can be affected by many variables, therefore it can and does change often. Both meteorological and local topography play an important role.

Looking back at the figures for 2020 which were published by IQAir.com, it can easily be seen that the air quality remained at a “Moderate” level throughout the year. To be classified as such the readings must fall between 12.1 and 35.4 µg/m³. The month that returned the cleanest air was January with a reading of 12.6 µg/m³. At the other end of the scale, the month with the dirtiest air was December with a figure of 24 µg/m³.

Historically, air pollution records were first kept in 2019 when the figure was 13.7 µg/m³ followed by 2020 with a figure of 18.5 µg/m³. This is quite surprising as it may have been affected by the COVID-19 pandemic as many vehicles were no longer in daily use as staff were 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. But this usually gives a better reading, not worse.

What is the main source of air pollution in Yazd?

Constant sources of pollution are thought to be factories, industries and vehicle use, which pollute the city of Yazd more than any other. These sources, which include public and private vehicles, affect Yazd province less than other metropolitan cities, while the sources of pollution are more constant.

Fixed resources include commercial, domestic and most importantly sectors including factories and industries, noting that the source of air pollution in Yazd is the activity of factories and industries, winds that often blow from northwest to southeast of Yazd lead to the transfer of contaminants.

The air pollution measuring stations in the province showed that most of the pollution in the city is affected by suspended particles that have a natural origin and lead to respiratory and heart diseases.

Existence of desert areas, low rainfall, existence of more than 20 wind erosion centres, daily traffic of more than 400,000 vehicles, existence of the same number of motorcycles in the province, establishment of 80 per cent of production units and population in Yazd-Ardakan plain and an increase of mining activities. All of these factors contribute to the poor air quality.

What can be done to reduce air pollution in Yazd?

In general, performing all pollution reduction activities, including the installation of filters, leads to a 90 per cent reduction in pollution and 10 per cent of smoke leakage. It was reported that 90 per cent of the province’s industry cooperate with this pollution monitoring unit.

Ignoring the primary and secondary environmental warnings, which include being included in the list of polluting industries, led to the closure of a steel factory in Ashkzar and a tile factory in Taft during the Nowruz period.

The comprehensive plan to reduce air pollution in the Yazd Ardakan axis, conducting a study plan on the subject (study and identification of dust generating centres in the province and provide management and executive solutions to control them), definition of livestock and poultry zones based on the principles of planning in order to prevent the dispersal of work and destruction of basic resources, the proposal to define industrial zones in suitable places for the establishment of heavy and polluting industries, including programs considered by the General Department of Environmental Protection to reduce pollution in Yazd-Ardakan plain. These are all suggestions as a way of reducing air pollution in the environment.

What effects does polluted air have on human health?

According to research by international organizations, pollution, especially air pollution, plays an important role in the development of non-communicable diseases and in incurable cases such as cancer. In addition, according to public health experts and practitioners, the phenomenon of air pollution affects the internal organs of the body, such as the cardiovascular and respiratory systems, as well as external organs such as the eyes and skin, which are directly exposed to air pollution.

There have not been many studies on the genetic effects of air pollution during the foetal period, but studies have shown that air pollution can activate the gene responsible for autism and cause it in humans. For this reason, in recent years there has been an increase in the incidence of children with autism due to air pollution.