Air pollution has been an issue for hundreds of years. All the way back in 900 an B.C.E. Egyptian king complained about stinky air by asphalt mines. In the 1300s, the air in England became so polluted from coal burning that King Edward I outlawed it and threatened to behead anyone caught burning coal again. Today, air pollution is outside and inside, and even though we often can't see or smell it, there's almost always something in the air that shouldn't be there.