Environmental issues in Syria Attacks on oil refineries can cause oil fires which release harmful chemicals into the air, such as sulfur dioxide, nitrogen dioxide, carbon monoxide and polycyclic aromatic hydrocarbons (PAHs). The sulphur and nitrogen compounds are linked to acid rain which can have dire impacts on vegetation as well as cause soil acidification. PAHs persist in the environment for long periods of time and are known carcinogens. Syria also extracts heavy crude oil, which generally has a higher proportion of noxious substances, including heavy metals, making it especially dangerous when these substances seep into the soil. Syria has two oil refineries. The
Sulfur dioxide Io, and in the crust and mantle of Europa, Ganymede, and Callisto, possibly also in liquid form and readily reacting with water. Sulfur dioxide is primarily produced for sulfuric acid manufacture (see contact process). In the United States in 1979, 23.6 million tonnes (26,014,547 US short tons) of sulfur dioxide were used in this way, compared with 150 thousand tonnes (165,347 US short tons) used for other purposes. Most sulfur dioxide is produced by the combustion of elemental sulfur. Some sulfur dioxide is also produced by roasting pyrite and other sulfide ores in air. Sulfur dioxide is the product of