Iran’s diesel contains sulfur levels up to 15,000 parts per million (PPM), far above the global standard of 10 PPM, a senior industry representative said, warning that poor-quality fuel is contributing to severe air pollution in major cities.
Hamid Hosseini, spokesperson for the Union of Petroleum Products Exporters, told Didban Iran on Sunday that even Afghanistan does not permit diesel above 2,000 PPM. He said Iran must invest in desulfurization technology to meet international standards.
“Our diesel has about 10,000 to 15,000 PPM of sulfur, while the global standard is 10,” he said.
Hosseini said Iran has the technical ability to produce Euro-4 and Euro-5 standard gasoline, but high domestic consumption leaves the oil ministry little choice but to distribute lower-octane fuel.
High-quality gasoline produced at some refineries is mixed with lower-quality batches before reaching the distribution network, he added.
He said pollution is also driven by aging vehicles and heavy diesel use in urban areas.
Nearly half of Iran’s 20 million registered cars are classified as old or high-emitting, while about four million motorcycles operate in Tehran alone.
Hosseini said Iran consumes roughly 120 million liters of gasoline per day and that scrapping older vehicles could significantly reduce both fuel use and emissions.
He added that sanctions have also limited investment in refinery upgrades, affecting the country’s ability to consistently produce cleaner fuel.
