Noise and wellbeing

Hearing loss is not the only harm caused by excessive noise

While hearing loss is one potential impact of high noise levels, there are a variety of other significant links between noise and wellbeing.

It’s well known that exposure to excessive amounts of noise can have an adverse impact on people’s hearing, potentially resulting in noise induced hearing loss (NIHL) and temporary threshold shift, sometimes referred to as auditory fatigue.

However, there are numerous less well known effects from noise. These may directly or indirectly impact our wellbeing in other ways, but are often not identified as possible forms of harm. Noise can exacerbate other health conditions, and some individuals are more sensitive to noise than others, and will therefore suffer harm more readily through exposure.

What’s the connection between noise and wellbeing?

All of us have probably complained about an “annoying” noise at some point or another. Noise typically provokes this annoyance when it affects our communication or concentration, and this can also lead to other cognitive and emotional responses.

Tinnitus

In terms of noise and wellbeing, tinnitus – a term used to describe the sensation of hearing a sound in the absence of any external sound – is not uncommon. Symptoms may include ringing, whooshing, humming or buzzing in the ear.

If there is a change in your auditory system, for example if you suffer from hearing loss or an ear infection, the amount of information being sent to the brain changes. The brain responds to this change in levels by trying to get more information from the ear, the extra ‘information’ you may experience comes as sounds we call tinnitus. Tinnitus is actually brain activity – and not the ear itself providing the ‘information’.

Common across all age groups, it’s estimated that 30% of people will experience tinnitus temporarily at some point in their lives, while 10% will live with a more persistent form of the condition. It can’t always be prevented and there are many causes and reasons why people experience tinnitus, including infections, stress and anxiety, and of course, loud noise.

Blood pressure

Many occupational studies have suggested that individuals chronically exposed to continuous noise at levels of at least 85 dB have higher blood pressure than those not exposed to noise. In many of these studies, noise exposure has also been an indicator of exposure to other factors (physical and psychosocial) which are also associated with high blood pressure.

The long-term negative effects of high blood pressure are well known and can result in:

• Stroke
• Heart attack/failure
• Vision loss
• Kidney disease/failure
• Sexual dysfunction.

Stress

The fundamental purposes of our hearing is to alert us to our surroundings, and as a result, sound directly evokes emotions and actions from us. Noise can therefore start our ‘fight or flight’ response complete with higher levels of noradrenaline, adrenaline and cortisol hormones released in response to stress and danger.

This can be good when the loud noise is something that we need to be aware of, such as a car hooting at us to get out of the way, or a fire alarm going off: in these circumstances we need to be ready to act. But when that response is always turned on because you’re chronically exposed to noise, then the noise itself can be a chronic stressor.

Chronically high cortisol can result in:

• Gut dysfunction/Irritable Bowel Syndrome (IBS)
• Weight gain/metabolic damage/insulin resistance
• Mood disorders
• Sleep disorders
• Weakened immune response.

Pregnancy

Exposure of pregnant workers to high noise levels can affect the unborn child. A large cohort study carried out by the Institute of Environmental Medicine (IMM) in Sweden showed that noise exposure during pregnancy can damage an unborn child’s hearing, with an 80% increased risk in noisy occupational environments.

Results showed that for the group of part-time and full-time workers, the adjusted hazard ratio (HR) for hearing dysfunction associated with maternal occupational noise exposure greater than 85 dB versus less than 75 dB was 1.27. For full-time workers as a group, the HR was 1.82.

This study shows how imperative it is for employers to control and reduce noise in the workplace. Even if pregnant women themselves use ear protectors in noisy environments, the babies they’re carrying remain unprotected.

Exacerbating other risks

Excessive levels of noise, or distracting noises, can also increase the likelihood of accidents by:

• Distracting workers, such as drivers
• Making it harder for people to hear and understand instructions correctly
• Masking the sound of approaching danger and warning signals
• Increasing levels of irritation and annoyance that may lead to human error.

What now?

Loss of hearing can have a huge impact on an individual’s personal and work life – and once hearing is damaged, there’s currently no known cure or effective treatment.

Wellbeing impacts go well beyond loss of hearing from excessive noise levels: there are a number of other ways we can be harmed, some of which are interlinked. These other types of harm may also manifest themselves a lot sooner than noise induced hearing loss, or can even affect our unborn children.

Noise and wellbeing are inextricably linked. If you have high noise levels in your workplace, you should do all you can to eliminate or reduce these at source. If that’s not possible, look to other means such as procedural controls, or as a last resort, hearing protection.