The effect of swimming in chlorinated water on middle ear pressure

This study evaluated whether an important fall in middle ear pressure (MEP) was recordable several hours after swimming. MEPs were measured in 52 normal school children on an average of four occasions immediately before swimming and "control" exercise sessions, and were repeated four hours after the activity. Twenty-nine children swam in a high chlorine concentration, with a mean free chlorine level of 2.3 parts per million, and 23 children swam in a low chlorine environment, with a mean concentration of 0.4 parts per million. For the former there was an average decrease of 0.5 daPa after swimming and an increase of 34.7 daPa after exercise; for the latter there were increases of 13.3 and 15.6 daPa after swimming and exercise respectively. It is concluded that swimming does not adversely affect middle ear function. Exercise induces an increase in MEP, and exposure to high chlorine levels appears to cause a small reduction in middle ear pressure.