Doctors have known for a long time that extremely loud noises can cause hearing damage or loss. The noise can be the sound of a jet airplane or machines in factories of loud music or other common sound at home and at work. A person only needs to hear the noise for little more than one second to be affected. An American scientist has found that using aspirin ( 阿司匹林 )increase the temporary ( 暂时的 ) h earing loss or damage from loud noise. He did an experiment, using a number of male students at a university who all had normal hearing. He gave them different amounts of aspirin for different periods of time, and then he tested their hearing ability. He found that students who were given four grams of aspirin a day for two days suffered much greater temporary hearing loss than those who did not use aspirin. The hearing loss was about two times as great. The scientist said millions of persons in the United States use much larger amounts of aspirin than were used in the study. He said these persons face a serious danger of suffering hearing loss from loud noise.