In Tehran, Iran's sprawling capital of 14 million people, the combination of cold winter air and emissions from millions of cars, trucks, and motorcycles creates a sometimes lethal fog of pollution.
The city has often ground to a halt, with emergency rooms filling up with patients and schools, government offices, and businesses shutting down due to the thick smog. One day last month, 400 people were hospitalized and another 1,500 sought medical treatment for pollution-related illnesses.
Cancer specialists and government health officials regularly link rising levels of pollution to Iran's growing cancer rate. In November, famed Iranian actor Reza Kianian announced that the government would launch a campaign to highlight "the cancer tsunami" following the deaths by cancer of pop star Morteza Pashaei, cinematographer Azim Javanruh, actor Majid Bahrami, and footballer Gholamhoseyn Mazlumi, all within a month of each other.
In 2012, 80,000 in the country died prematurely due to pollution, according to official figures.
'You can even smell it is different than before.'
This public health epidemic has escalated since 2010, when the US government imposed tough sanctions on Iran's energy sector, targeting companies that sell refined gasoline to Iran or supply the country with refining equipment. Prior to the sanctions, the Islamic Republic imported up to 40 percent of its gasoline because it has insufficient domestic refining capacity. Now, it blends dangerous petrochemicals on an industrial scale in order to fill the yawing supply gap.
"During the winter we deal with thousands of elderly patients with heart and respiratory problems from the pollution, and asthma cases in children are also rising," Sepideh, a nurse at a hospital in Ahwaz, told VICE News. Located in southwest Iran, Ahwaz is the most polluted city on earth, according to the World Health Organization. "The situation has become much worse since Iran started producing so much domestic gasoline. You can even smell it is different than before."
US sanctions are ostensibly aimed at constraining Iran's nuclear program. But comments from some American politicians reveal a goal of targeting the Islamic Republic more generally. In 2011 Representative Gary Ackerman, a New York Democrat, said sanctions were meant to "inflict crippling, unendurable economic pain over there" and to make Iran's banking system — the means by which it traditionally imports everything from pharmaceuticals to grain — "the financial equivalent of Chernobyl: radioactive, dangerous and most of all, empty".
Paul Sampson, an analyst at Energy Intelligence, said the sanctions have forced Iran to be creative — albeit by compromising air quality. "They've been putting petrochemical components like benzenes and Methyl Tertiary-Butyl Ether into the gasoline, which has increased overall supplies but reduced the quality," he told VICE News. "Some of the stuff is more suitable for tractors or Ladas, the Soviet cars built to run on low-grade gasoline."
Amid the economic blockade, plummeting oil prices, and a currency collapse that has hit both ordinary Iranians and state coffers, the technocratic cabinet of the reformist-backed president Hassan Rohani is seeking to address Iran's gasoline problem at the same time as cutting pollution and improving public health.
Oil minister Bijan Zanganeh has prioritised boosting Iran's domestic refining capacity. The Abadan Refinery, built in 1912 and badly damaged during the Iran-Iraq War, is being revamped to produce high-quality gasoline at a rate of 400,000 barrels per day. And the Persian Gulf Star Refinery is reportedly nearly completed, with refining capacity of 120,000 barrels per day.
But hobbled by sanctions, the government knows the only way to really curb pollution is to reduce Iran's fuel consumption, which stems from generous state fuel subsidies. Seeking to cut the Gordian Knot, President Rohani raised petrol prices by 75 percent in April, from 4,000 to 7,000 rials ($0.16 to $0.28) per litre. The Islamic Republic spends $40-100 billion every year on subsidies on fuel, food, and water — inordinately expensive for a government in financial disarray and the primary reason for Iran's souring fuel consumption.
To make matters worse, Iranians of all stripes, from truck drivers to government bureaucrats, smuggle millions of barrels of cheap fuel out of the country to traders in Turkey, Iraq, and Afghanistan. Cross-border bus drivers sometimes carry extra tanks of fuel to sell for a profit after they leave the country. Iranian and Iraqi Kurds have traded gasoline for alcohol since the birth of the Islamic Republic in 1979.
Iran has responded recently by charging Turkish truck drivers steep tariffs to make up for the shortfall in fuel brought about by cross-border smuggling. Turkey has been responding in kind. Last year, trade across the Bazargan-Dogubeyazit border ground to a halt, costing both economies millions of dollars.
Ali Dadpay, an economist at Clayton State University, says Iran is spending its valuable — and rapidly depleting — foreign currency reserves on importing significantly more gasoline than it needs because of demand created by its lavish fuel subsidies.
"If the price regime is reformed by raising prices towards the true market rate, then overall Iran will need to produce less low-quality gasoline, which will cut pollution significantly," Dadpay told VICE News. "Even though they seem high, the subsidy cuts are not making a dent in demand, partly because there are so many exceptions to the cuts, which are all too often exploited and sold on to smugglers."
But President Rohani will find it difficult politically to hike prices even more. The currency collapse and rampant inflation — both stemming from US sanctions — have made the average Iranian significantly poorer. The president may lose popularity if the economic medicine he prescribes is too bitter for the public to swallow, especially in the run up to parliamentary elections in 2016, which conservatives hope to win by appealing to Iran's poor and disenfranchised.
Then there are the corrupt officials who benefit from the sanction economy by running a black-market trade in fuel. Although sanctions are hitting both the health and the financial security of millions of ordinary Iranians, some are making millions from the smog.
_Follow Arron Merat on Twitter: _@a_merat