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。