The occupational groups most likely to get tinnitus are automotive industry workers, drivers and farmers.
Older male car workers are most likely to report tinnitus, data from the Australian Workplace Exposure Survey has shown.
 The 2016 survey of about 5000 working-age people, published in the MJA, showed around one in four said they experienced ringing, buzzing or other unexplained sounds in their ears, at least occasionally.
Most of the symptomatic cohort were classified as occasional sufferers, the researchers said. But 345 people â or 7% of the overall sample â had constant tinnitus.
The study found the strongest associations with the incidence tinnitus were male sex and older age. One in six men aged 55 to 64, the oldest age group counted in the survey, had constant tinnitus.
âConstant tinnitus seems happen more to men, and it certainly is something [to keep in mind when assessing] menâs health,â study lead author Katherine Lewkowski told The Medical Republic.
âTinnitus is associated with lack of sleep, can be linked to anxiety and depression and it does affect quality of life.â
In terms of occupational groups, the top five professions where workers reported tinnitus were the automotive industry, driving and transport, farming, other trades and the construction industry.
Audiologist Ms Lewkowski said while a high incidence of tinnitus was expected for most of these occupational groups, the research team had been somewhat surprised at drivers taking out the second place.
âOne of the highest risk factors for tinnitus is noise exposure, so we were expecting occupations with high noise,â she said.
âAutomotive mechanics have high noise exposure, farmers obviously have high noise exposure, so the one that threw us a little bit was drivers.â
For the purposes of the survey, the âdriversâ cohort encompassed a wide range of jobs including rideshare drivers, taxi drivers, bus drivers, truck drivers, delivery drivers and forklift operators.
â[The underlying cause of tinnitus] is not necessarily noise, although drivers do tend to have very long shifts [and are therefore exposed for long periods of time],â Ms Lewkowski said.
âBut one of the possibilities is that they’re exposed to something else in their workplace, and potentially that could be carbon monoxide, vehicle exhaust.â
Research into carbon monoxide ototoxicity is still in its infancy, but Ms Lewkowski said it currently seemed unlikely that carbon monoxide alone can cause hearing damage.
âOne of the interesting things from this research is that auto mechanics, being the number one group, are exposed to noise â but they are also exposed to a wide range of other chemicals, which include vehicle exhaust, petrol fumes and occasionally lead,â she said.
Ms Lewkowski said that while there is still no definitive cure for tinnitus, there has been some success in reducing symptom levels via cognitive behavioural therapy, as well as changing diet and stress levels.
âWe’re certainly beginning to understand more about tinnitus, and it’s not so much about fixing the ear,â said Ms Lewkowski.
âIt’s more about behavioural feedback and habituation techniques.â