Respiratory disease continues to be a major public health problem.
Chronic obstructive lung disease, chronic bronchitis and asthma continue to produce considerable morbidity and mortality. Environmental factors have long been recognized as important in the causation of these diseases. For example, there has been recent recognition that particulate air pollution may be accounting for excess morbidity and mortality, a problem with enormous regulatory significance, however, little is known about the nature of the particles people breathe. Investigators are only beginning to understand the true relationships of indoor and outdoor pollution with the various forms of respiratory disease. From the Children's Health Study, the two-part papers by Peters et al.