What causes asthma? Clues from London's Great Smog with implications for air pollution today
- Written by Jamie T. Mullins, Assistant Professor of Resource Economics, University of Massachusetts Amherst

Asthma is a chronic respiratory condition with no known cure. It impacts people of all ages through episodic constrictions of the airways, which may be even worse than it sounds. Approximately 334 million people worldwide suffer from asthma, including 24 million Americans and 5.4 million...