Fertilized soil may be a major source of smog near Salton Sea, researchers say

"Because it's relatively cheap, farmers will usually apply about twice as much fertilizer as needed by the crops, just to make sure they get it. So, when you have a bunch of excess nitrogen, microbes go to town and they start using it for fuel. But some of it leaks out of their metabolism and it comes out as this air pollutant."

"UC Davis researchers say the soil in the Salton Sea air basin emits more than 11 tons per day of nitrogen oxides - about 10 times more smog-forming pollution than California air regulator officials currently estimate."

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