Tehran’s air reached the unhealthy for sensitive groups range on Friday as pollutant concentrations climbed and meteorologists issued an orange alert for six major cities, warning that stagnant conditions could drive indices toward the dangerous threshold in the coming days.
The 24-hour average for fine particulate matter (PM2.5) stood at 103 on Friday, placing the capital in the category affecting children, the elderly and people with heart or respiratory conditions, the Tehran Air Quality Control Company said.
Morning readings reached 133, extending the hazard to a broader segment of vulnerable residents.
The US EPA Air Quality Index uses six color-coded categories to show rising levels of pollution and health risk. It starts with Good (0–50, green), where the air poses little or no threat. Moderate (51–100, yellow) signals acceptable conditions but possible effects for a small number of sensitive people. Unhealthy for Sensitive Groups (101–150, orange) warns of heightened risk for those with respiratory or heart conditions. Unhealthy (151–200, red) means everyone may begin to feel adverse effects. Very Unhealthy (201–300, purple) marks a serious increase in health concerns. At the top of the scale, Hazardous (301+, maroon) indicates dangerous conditions where the entire population may face severe health impacts.
Prolonged stability expected to worsen pollution
Tehran, Isfahan, Tabriz, Karaj, Ahvaz and Mashhad were listed as the cities most at risk of severe deterioration.
The stagnant pattern is likely to persist, Sadegh Ziaian, an official at the National Meteorological Organization, said on Thursday.
“An increase in pollutant concentrations in the major cities is certain,” he said, adding that only parts of Iran’s eastern belt would see winds strong enough to disperse particulates. “Tehran’s sky will remain clear with local haze, and air will reach unhealthy levels for all groups.”
Public health toll and calls for systemic reform
The health ministry has repeatedly stressed the human cost of chronic pollution. 58,975 deaths in the past Iranian year were attributable to poor air quality, an average of 161 a day, with economic losses estimated at $17.2 billion, according to Deputy Health Minister Alireza Raisi.
Meteorologists advised residents and authorities to curb non-essential travel, manage fuel consumption, restrict polluting industrial activity and avoid outdoor exercise. Environmental specialists continue to urge long-delayed measures – from retiring aging vehicles to expanding cleaner energy – warning that without structural reforms, cities such as Tehran will remain trapped in cycles of hazardous air and mounting health impacts.
The Foreign Ministry said the measure, backed by the United States and three European powers, has further undermined the credibility of the International Atomic Energy Agency.
Foreign Ministry spokesperson Esmail Baghaei said Tehran informed the Agency in an official letter that the understanding reached in Cairo in September is now considered void. “The so-called Cairo accord, which had been achieved through lengthy negotiations and Iran’s goodwill, is no longer valid,” he told state media.
Baghaei said the resolution showed “a clear misuse of an international body to advance the interests of the United States and three European countries.” He said Tehran will take reciprocal measures but did not give details.
In a separate statement early Friday, the Foreign Ministry described the IAEA Board of Governors’ resolution as “illegal and unjustified.” It said the measure was imposed under US and European pressure and “represents another example of their irresponsible behavior and misuse of the Agency to apply political pressure on Iran.”
The statement said the resolution violated the fundamental principles of the Non-Proliferation Treaty, which guarantees every member’s right to peaceful nuclear energy. It also said the board has “no legal authority” to revive Security Council resolutions that have already expired.
According to the ministry, “The United States and three European countries ignored Iran’s responsible and good-faith conduct, disrupting the positive path that had emerged between Iran and the Agency, and forced Iran to declare the termination of the September 9 understanding.”
The statement added that under that understanding, Iran and the Agency had resumed cooperation and allowed limited inspections of some nuclear facilities.
The IAEA Board of Governors on Thursday adopted a Western-backed resolution urging Iran to grant full access and information about its nuclear program. Diplomats said the measure passed with 19 votes in favor, three against and 12 abstentions. Russia, China and Niger voted against it.
The resolution calls on Iran to allow the Agency to verify its stock of enriched uranium and inspect atomic sites damaged by US and Israeli airstrikes in June. It also asks Iran to provide “without delay” data on nuclear material and safeguarded facilities.
Foreign Minister Abbas Araghchi said on Thursday the resolution effectively nullified the Cairo accord, an interim deal reached with IAEA Director General Rafael Grossi and Egyptian mediation. The agreement had aimed to restore limited inspections at facilities hit during the June conflict.
Iran links dispute to June attacks
Tehran says the IAEA resolution ignores what it calls the illegal US and Israeli attacks on its nuclear sites, which killed scientists and halted inspections. “Neither in the resolution nor in the statements of the United States and the three European countries is there any mention of those attacks,” Baghaei said.
Iranian officials have said the attacks caused a sharp drop in cooperation with the Agency because of safety concerns and political mistrust. Araghchi said this week that Tehran continues cooperation under the Non-Proliferation Treaty for facilities such as the Bushehr power plant but will not allow inspections at bombed sites.
‘West seeks dictation, not negotiation’
Araghchi said in a separate interview that Washington and its allies are seeking to impose demands rather than hold genuine talks. “They want us to accept zero enrichment and limits on our defense capabilities,” he said. “This is not negotiation. This is dictation.”
He said the United States has offered to close the Security Council file on Iran if Tehran accepts “unacceptable” conditions. “After the war they could not achieve their goals through force. Now they want to achieve them through pressure and so-called negotiation,” he said.
Baghaei said the new resolution will make it harder for the Agency and Iran to work together. “By disregarding Iran’s goodwill and cooperation, these countries have damaged the Agency’s credibility and independence,” he said.
