Pollution and asthma. Atmospheric hydrocarbons and asthma

There is a link between an increase of respiratory symptoms, including increased  emergency room visits and high concentrations of atmospheric hydrocarbons.

High concentration of atmospheric pollutants started about 50 years ago as a consequence of an increase of industrial and domestic use of liquid petroleum gas, kerosene or diesel fuel

How do we know if it’s really the pollution contaminating or it is because naturally occurring contaminants outdoors.  

Some very interesting studies were done in Japan. There you can find some cedar woods with it’s pollen that might be a trigger of respiratory symptoms. Also there are some inner city cedar -lined roads with heavy traffic. Pollen counts were similar in both places. But the amount of people with asthma living near those roads with heavy traffic was significantly bigger.

See also other personal cases and other articles on pollution and asthma