About a fourth of workers might be experiencing ringing in their ears and certain jobs increase their risk.
Workers in construction, the automotive industrty, transportation and agriculture tend to report higher rates of tinnitus — or the perception of sound in one or both ears when no external sound exists.
A study of survey data by Australian and Norwegian researchers found that of 5,000 adult workers, nearly 27 percent reported ringing in their ears. Of that group, about 7 percent have constant tinnitus. The study was published in the Medical Journal of Australia.
They found that constant tinnitus was higher among automotive workers, with 16.7 percent reporting sound that never goes away. About 13 percent of drivers and 12 percent of farmers also reported constant tinnitus.
Workers most likely to suffer from constant ear noise were male workers ages 55 to 64.
There is still some disagreement as to why this high incidence of tinnitus occurs. The lead author of the study, Kat Lewkowki, an audiologist, said workplace conditions were probably at play. A co-author, Lin Fritschi, thinks chemical exposure could also play a role, especially in transportation where carbon monoxide exhaust may be a factor.
Noise exposure is a documented risk for tinnitus.