“Although there has been a decline in sulphur levels compared to summer, aromatic compounds and benzene are still above acceptable levels,” Zahra Samaee was quoted as saying by ISNA.
As part of the study, regular and premium (unleaded) gasoline samples were collected at random from 163 gas stations and the results revealed relatively high levels of aromatic hydrocarbons, Financial Tribune quoted her as saying.
It was found out that the quantity of the hazardous elements in gasoline (aromatic compounds and benzene) was 40% and 1.4% respectively -- above levels set by the European Union (35% and 1%).
DoE added that the average sulfur content in gasoline samples was estimated at around 70 PPM. Last summer the figure was180 PPM.
The study analyzed diesel samples from several gas stations, which were also found to have high levels of sulfur. Average sulfur content in the fuel amounted to 150 PPM. The content was 600 PPM last year.
Environmentalists, experts and independent observers link the worsening air pollution in mega cities largely to the poor quality of fuels produced in domestic refineries.
However, Alireza Sadeqabadi, managing director of National Iranian Oil Refining and Distribution Company, puts the blame on the automakers and their monopoly that has been manufacturing substandard vehicles for the past three decades, apparently with utmost irresponsibility.
Data routinely published by Tehran Air Quality Control Company show that the levels of toxic pollutants in the air breached critical levels several times in the past three months, especially in November.
Charts published on TAQCC’s website, airnow.tehran.ir, illustrate that Tehran residents did not see the clear blue sky at all in November, as the air quality index did not come 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).
Close to 75 million liters of diesel is used in Iran on a daily basis.
Sulfur is a natural component in crude oil that is present in gasoline and diesel unless removed. Reducing sulfur content in gasoline enables advanced emission controls and reduces air pollution.