Speaking on Friday, Hanachi emphasized that the burning of fossil fuels, excessive use of private cars and the growing number of low-quality motorcycles are the main culprits causing air pollution in the megacity, IRIB News reported. 

According to urban managers, the severe trade restrictions facing Iran due to US sanction have hampered the expansion of public transportation fleet. Plans to purchase new buses and add more train wagons to the city's subway network have ground to a halt.

According to Hanachi, there seems to be no alternative at present for curbing the motorbike numbers, Financial Tribune reported.

Due to the recent economic headwinds, the price of vehicles and motorcycles has seen a threefold jump, just like any other commodity.

After US President Donald Trump reneged on Iran’s nuclear accord and reimposed sanctions against Tehran last summer, the Iranian rial lost almost 70% of its value over the past year. 

On Sunday, the US dollar was traded at 130,000 rials in Tehran while it hardly fetched 42,000 rials in March 2018.

Following the reimposition of sanctions, many foreign suppliers of vehicles and parts suspended collaboration with Iranian firms. The country cannot afford to import new buses in large numbers and local manufacturers do not have the technology, machinery and the means to produce indigenous, eco-friendly buses.

However, Hanachi outlined some of the compensatory measures taken to alleviate the problem, including installation of smog filters on 50 buses as a pilot scheme. 

"The filters can absorb up to 90% of toxic emissions released from the vehicles," he said.

“Increasing the share of domestically-made subway wagons can be helpful in addressing the slow development of the subway network. At present, the domestic capacity of train car production hardly reaches 30% of the demand.”

Hanachi called for patience, as he promised to overcome the challenges. 

Earlier this month, Tehran’s mayor had wistfully said the only way out of the current smog crisis facing the megacity is to hope for the helping hand of Nature. 

“If wind were to blow our way, the situation would improve,” he said.

Over the past few decades, as Tehran expands in all directions, mayor after mayor has failed to address the issue effectively.

They have failed to relocate some of the most polluting industries, such as cement and asphalt factories, out of the capital city.

Air Quality Status

The Iranian capital has been suffocating under a blanket of smog that has refused to budge over the past few weeks, excluding a day or two, when scattered rainfall eased the pollution partly. However, toxic emissions again enveloped the city and pushed up the air quality index to alarming levels.

Data regularly published by Tehran Air Quality Control Company show that the levels of toxic pollutants in the city's air breached critical levels several times in November.

Charts published on TAQCC’s website, Airnow.tehran.ir, illustrate that in the month-long period, Tehran’s residents did not see clear blue skies at all, as the air quality index did not fall under 50 during the month.

The index categorizes conditions dictated by a measure of polluting matters into good (0-50), moderate (51-100), unhealthy for sensitive groups (101-150), unhealthy (151-200), very unhealthy (201-300) and hazardous (301-500).

In 11 days, the AQI held on to the "moderate" status.

Besides, sensitive groups in the capital were warned to limit their outdoor activities in 18 days, as the index entered the threshold of 101-150 that categorizes the condition as “unhealthy for sensitive groups”.

Children, the elderly, pregnant women and those with respiratory and cardiovascular conditions fall in the above group.

AQI breached the threshold of "unhealthy" status for all groups on November 29, compelling the officials to take prompt decisions.

Pollutants measured to determine air quality include carbon monoxide, nitrogen dioxide, sulfur dioxide, ground-level ozone and particulate matter (PM2.5 and PM10). AQI figures are calculated as per the concentration of pollutants.

Analyses illustrate that the pollutant responsible for the 19 highly polluted days recorded in the period under investigation was PM2.5 (atmospheric particulate matters that have a diameter of less than 2.5 micrometers).

Air quality in the corresponding month of 2018 was more satisfying, as "moderate" condition dominated the period with AQI standing between 51 and 100 for 22 days.  In November 2018, AQI showed "good" status for two days. 

Sensitive groups in the capital were warned to limit their outdoor exposure for the remaining seven days.

Since the beginning of the current Iranian year (March 21), Tehran has passed two days with "unhealthy" air condition for all groups, 48 days with "unhealthy" status for sensitive groups, 187 days with "moderate" and 25 days with "good" air quality condition.

Health Hazards

As the fourth leading cause of premature deaths worldwide, toxic air leads to heart disease and stroke, lung cancer and respiratory infections.

According to a report released by the Iranian Legal Medicine Organization, during the fiscal year that ended in March 2017, some 12,000 air pollution-related deaths were reported in Iran, with one-third of the fatalities recorded in the capital.

Recently, an official with the Department of Environment told media outlets that air pollution annually costs Tehran residents $2.6 billion, which implies that air pollution inflicts a loss of $300 on each resident of the capital.

Based on a Saturday report by Tehran Emergency Center, the persistent toxic pollution in the capital city has forced over 8,400 respiratory and cardiovascular patients to approach medical emergency centers in Tehran in the past 10 days.

Millions of people work and live in Tehran. They all need decent transportation. However, government and municipality coffers are lacking in funds when it comes to paying for upgrading or expanding public transportation services.

They also do not have the means to extend loans to owners of dilapidated vehicles for replacing them with more efficient vehicles.

Given the absence of long-term initiatives and the lack of determination to combat air pollution on a war footing, citizens will continue to suffer in the foreseeable future in Iranian metropolises.