Air Pollution and its Effects on Global Health

Outdoor air pollution is known to cause millions of deaths worldwide; it also increases the risk of respiratory and car-diovascular diseases [1]. In 2012, the WHO reported 3.7 mil-lion deaths attributable to ambient air pollution and 4.3 mil-lion deaths due to household air pollution. In new estimates, it reports that one in eight of all global deaths are due to air pollution.This figure more than doubles previous estimates and confirms that air pollution is now the world’s largest single environmental health hazard [2]. Preventing or reducing air pollution can save millions of lives [2].Two of the most harmful urban air pollutants are nitric oxide and coarse particulate matter. In cities with rows of tall buildings a unique urban habitat known as a “street-can-yon” may develop trapping pollutants. Stagnant air lingers in street-canyons increasing the concentration of pollutants [1].Four of the 10 worst-polluted cities in the world according to the WHO, are in Iran. The number one slot was the indus-trial city of Ahvaz, which had three times the concentration of pollutants as Beijing. Tehran, a metropolis of over 8 mil-lion people, although not in the top 10 polluted cities overall, checks-in at number 82 (of 1099), with roughly four times the concentration of polluting particles as smog-blighted Los Angeles [3]. During periods of inversion, schools are can-celled; the sick and elderly are told to stay home; and people are banned from driving [4]. Tehran’s pollution was blamed on bumper-to-bumper traf-fic in a city wedged between two mountains trapping fumes. Pollution was exacerbated by domestic production and dis-tribution of low-grade petrol (with alarmingly-high num-bers of carcinogens and sulfur) when sanctions prevented Iran from importing gasoline. In 2013, the Health Ministry announced that people are dying from what they inhale and that 4460 Tehran residents died in 2012 from air pol-lution and that patients who had visited Tehran hospitals with heart conditions had increased by 30%.[3,4] The Ira-nian Environment Protection Agency took action towards the protection of the natural environment. One of the most important was cessation of production of gasoline by pet-rochemical units, [5] and the decision to import gasoline with the highest international standards (Euro 4) when sanctions were lifted. Air pollution has decreased dramat-ically since the temporary lifting of sanctions in January 2014. Last year, Iran had 147 days during which air quality was substandard. Two years ago, this number stood at 217 days [6]. Further research on air pollution and advance-ments in automotive technology (i.e. electric cars and mo-torcycles) are expected to lower environmental pollutants in the near future as hybrid vehicles are being imported.