Why would the rise in asthma attacks not be caused by air pollution?

It may be!: There are many theories about the reason for an increasing number of asthma patients. These include increased use of antibiotics (hygiene hypothesis), use of Acetaminophen in children, air pollution (diesel particles and particulate matter pm2.5), allergies, etc. Air pollution is a clear contributor to respiratory disease including triggering asthma already present and perhaps inducing asthma.