In addition to household contaminants, asthma can be precipitated by exercise, cold air, emotional stress, viral infections, everyday chemical agents such as aspirin, and industrial air pollutants, including ozone and mirogen dioxide.

• 除家庭污染之外，锻炼，冷空气和情绪紧张，病毒感染，日用化学制剂如阿斯匹林，以及工业造成的空气污染，包括臭氧和二氧化氮也可加剧哮喘。