A Bronchodilator is an Agent that causes an increase in the caliber (diameter) of airways.

In the environmental context, a bronchodilator is a medication or substance that helps to widen the air passages of the lungs, making it easier to breathe. This can be especially important for people who suffer from conditions like asthma, bronchitis, or chronic obstructive pulmonary disease (COPD).

Some examples of bronchodilators used in medicine include albuterol, salmeterol, and ipratropium. These medications can be delivered via inhalers, nebulizers, or orally.

In addition to medical use, bronchodilators can also be used in the environment to alleviate air pollution by widening air passages in plants and trees, which can help to increase their ability to absorb pollutants and reduce harmful emissions. For example, in urban areas, where air pollution can be a significant issue, applying bronchodilators to trees and plants may help to improve air quality. However, the use of bronchodilators in the environment is still a relatively new concept and requires further research to determine its effectiveness and potential risks.