Qualité de l’air à Ahvaz

What is the level of air pollution in Ahvaz now?

Ahvaz is a city in the southwest of Iran and the capital of the Khuzestan province. A census conducted in 2016 estimated the population to be approximately 1.3 million people. This almost doubles though if you include the metropolitan area of Sheybani with 1.1 million residents.

There is just one navigable river that flows through Iran and it passes through the centre of Ahvaz. This is the River Karun.

Halfway through 2021, Ahvaz was experiencing a period of air quality that is classed as being “Unhealthy for sensitive groups” with a US AQI reading of 144. This United States Air Quality Index figure is internationally recognised and endorsed by the World Health Organisation (WHO) as a standard set of metrics that is used to compare different cities in different parts of the world. Up to six of the most commonly found air pollutants are measured and this figure is then established. Sometimes information about all six pollutants is unavailable, so the figure is calculated using what information there is. The current figure was based on just two pollutants which were: PM2.5 - 52.2 µg/m³ and PM10 - 210.1 µg/m³.

With elevated levels such as these, it is highly recommended to stay inside and close all doors and windows to prevent the ingress of more dirty air from entering the room. Those with a sensitive disposition should refrain from venturing outdoors until the air quality improves. A good quality mask should be worn when going outside although prolonged periods of outdoor activity are not recommended until the air quality noticeably improves. The table at the top of this page will assist you with this decision. It would be very beneficial to use an air purifier if one is available.

Does the quality of air vary throughout the year in Ahvaz?

Air quality can be very volatile because it is affected by so many variables such as temperature, the speed and direction of the wind and the strength and hours of sunlight.

Looking back at the figures released by the Swiss company IQAir.com, it can be seen that the best quality air is found during the spring and summer months. The months of March and April showed figures between 12.1 and 35.4 µg/m³ which was classified as being “Moderate” quality. This was again the case for June and August with figures of 29.8 and 30.1 µg/m³, respectively. The remaining fragmented months of the year recorded levels that were classified as being “Unhealthy for sensitive groups” with figures between 35.5 and 55.4 µg/m³. All these figures are stated in micrograms or microns per cubic metre.

The annual average figure was recorded and was found to be 39.5 µg/m³. In 2020 most cities recorded a much lower than expected figure because of the restrictions imposed due to the COVID-19 pandemic. The air quality improved due to the prohibited use of most private vehicles and the suspension of production in many factories and similar companies.

What are the sources of all this polluted air in Ahvaz?

Transportation, extensive use of fossil fuels, outdated urban fleets of gasoline and diesel vehicles, industrial sources within and close to the city boundaries and natural dust are major contributing factors as are operations in the oil refinery sector.

Most cars use leaded gasoline and lack emissions control equipment. Due to international sanctions against Iran, the government allows the production of sub-standard gasoline. The city is also overrun with old and aging cars which do not meet current emission regulations.

Over the last few years, the region has become a centre for heavy industries, whether through oil and gas exploration there, seizing vast areas to build related refineries, and creating huge pipelines that extend across natural areas. All of this, along with other factors, has led to a heavily polluted area around Ahwaz.

Buses and cars running on natural gas are planned to replace the existing public transportation fleet in the future. Traffic management, vehicle inspection and the general use of electric bicycles are also part of the solution.

Major factories and power plants are being actively encouraged to use natural gas as a fuel instead of diesel which has a very high sulphur content.

How does this poor air quality in Ahvaz affect human health?

Short-term exposure to polluted air, such as ground level ozone, can affect the respiratory system because the majority of pollutants enter the body through the airways.

Short-term exposure to air pollution can also lead to respiratory infections and decreased lung function, in addition to exacerbating cases of people who suffer from asthma. Exposure to sulphur dioxide causes damage to the eyes and respiratory system, as well as skin irritation.

Much scientific research has been conducted on health problems due to long-term exposure to air pollution, and scientific research has linked air pollution to serious diseases including premature death, foetal deformity, lung cancer, and a number of other diseases such as lung cancer and cardiovascular disease.

Atmospheric particulate matter (PM) is a microscopic solid or liquid suspended in the air. Particle sources can be natural or anthropogenic. One of the biggest public health concerns is particles small enough to be inhaled into the deepest parts of the lung. These particles are less than 10 microns in diameter (about 1/7 of the thickness of a human hair) and are defined as PM10. It is a mixture of substances that can include smoke, soot, dust, salt, acids, and minerals. Particles are also formed when gases from motor vehicles and industry undergo chemical reactions in the atmosphere. PM10 is visible with the eye as the haze we think of as smog. PM10 is one of the most harmful of all air pollutants.

PM10 includes fine particles known as PM2.5, which are fine particles with a diameter of 2.5 microns or less. It is understood that the greatest public health impact of air pollution is from long-term exposure to a substance. PM2.5 increases the risk of death by age, especially for those with cardiovascular disease.

Long-term exposure to particulate pollution can result in significant health problems including:

• Increased respiratory symptoms, such as irritation of the airways, coughing or difficulty breathing
• Decreased lung function
• More frequent asthma attacks
• Development of chronic respiratory disease, especially in children
• Development of chronic bronchitis or chronic obstructive lung disease
• Irregular heartbeat
• Nonfatal heart attacks
• Premature death in people with heart or lung disease, including death from lung cancer.