No time to lose. Working together to beat occupational cancer.

What's the issue with solar radiation?

Sun exposure can cause skin cancer. And exposure to the sun is the main cause of skin cancer. The fact that skin has changed colour after being exposed to the sun shows that it’s being damaged. Sunburn is a reaction to over-exposure to ultraviolet (UV) light. The top layers of skin release chemicals that make blood vessels expand and leak fluid causing swelling, pain and redness. Without protection from the sun, UV starts to penetrate deep into the layers of the skin and damages skin cells, which can lead to the cell mutations associated with cancer.

Worldwide, over-exposure to the sun is the main cause of both malignant melanoma and non-melanoma skin cancer. Malignant melanoma is an aggressive form of cancer, less receptive to treatment than non-melanoma skin cancer, and has a higher death rate, especially if diagnosis is delayed and the cancer spreads.  

Non-melanoma skin cancer, which includes basal cell (rodent ulcers) and squamous cell carcinoma, is rarely fatal but requires treatment and sometimes minor surgery. This can be disfiguring, particularly on the head and neck. Both non-melanoma skin cancer and malignant melanoma have been shown to be associated with chronic exposure to UV, typically experienced by many outdoor workers. Although, for malignant melanoma, intermittent sun exposure and sunburn history are considered particularly important. 

Lack of awareness

Awareness of solar radiation risks is generally poor, according to research into sun exposure in the United Kingdom (UK) construction sector. Two thirds of workers outside for an average of nearly seven hours a day thought they were not at risk or didn’t know whether they were or not. The study – commissioned by IOSH from the University of Nottingham – also found that 59 per cent of construction workers reported having sunburn at least once in the last year (2017). Just over 40 per cent thought there was no need to wear sunscreen on a cloudy day. Most didn’t use measures to protect themselves against sun exposure. Both workers and managers didn’t see sun safety as an important issue, mainly because of a misperception that the climate in the UK does not pose a high risk of skin cancer. 

Other research commissioned by IOSH into sun exposure at work in Britain found that malignant melanoma (the more serious form of skin cancer) kills nearly 50 people each year, with 240 new cancer cases being registered. The majority affected are men, and just under half those diagnosed with malignant melanoma linked to occupational exposures are under 65. These findings, from Imperial College London, are echoed in studies from around the world, including North America, Australia and other European countries. In addition, at least 1,500 new cases of work-related non-melanoma skin cancer (more treatable than malignant melanoma) are also registered each year in Britain, with 12 deaths. Imperial College’s research shows that 55 per cent of work-related non-melanoma skin cancer cases and 42 per cent of malignant melanoma cancer cases involve construction workers – other key sectors include agriculture, public administration/defence and land transport. 

The International Agency for Research on Cancer (IARC) has classified solar radiation, the use of UV-emitting tanning devices and UV as carcinogenic to humans. 

Fact: currently, between 2 and 3 million non-melanoma skin cancers and 132,000 melanoma skin cancers occur globally each year. One in every three cancers diagnised is a skin cancer (World Health Organization).

Other health concerns from sun exposure 

UV exposure can also cause other health conditions, such as: 

  • sunburn from the sun or artificial devices
  • premature ageing of the skin and wrinkles, liver spots, actinic keratosis and solar elastosis
  • weakening of the immune system, which can lead to reactivation of herpes (triggered by sun exposure) and cause vaccines to be less effective
  • eye conditions, such as: 
    • inflammation of the cornea 
    • cataracts 
    • eye cancer 
    • photokeratitis and photoconjunctivitis 
    • pterygium and pinguecula. 

All of the conditions can impair vision. 

Some medications can make people more sensitive to UV exposure and some medical conditions can be made more severe. 

How dangerous is solar radiation for your organisation?

This depends on what people involved with your organisation do, and the country you operate in. 

Exposure will vary according to: 

  • the time of day – strongest between 10am and 4pm
  • the time of year – stronger during the spring and summer seasons
  • the latitude (distance from the equator) – UV exposure increases the closer you are located to the equator
  • the altitude – the higher the elevation, the more UV reaches the location
  • the clouds – clouds can cause various effects, but UV can still reach the ground when clouds are present
  • the surrounding surfaces near the working area – for example, water, snow, ice, sand, pavements and grass can reflect UV, increasing the exposure
  • the air concentration – the o-zone layer in the Earth’s atmosphere can filter out some UV 
  • what substances are being used – some substances can increase photosensitivity. 

An individual worker’s skin type is particularly important. Skin type affects how skin reacts in the sun and how likely individuals are to develop skin cancer. Remember that skin type is genetic – it doesn’t vary according to how ‘tanned’ someone is. The Fitzpatrick skin type scale is used to classify skin types based on six categories, I to VI. The scale is used by medical professionals. 

Those that fall into categories I or II skin are at a higher risk of developing skin cancer when exposed to UV. However, it is important to remember that anyone exposed to UV can develop skin cancer regardless of their skin type. 

Graphic showing the Fitzpatrick scale for classifying skin types. Type 1 is light, pale white. Type 2 is white, fair. Type 3 is medium to olive. Type 4 is olive, moderate brown. Type 5 is brown, dark brown. Type 6 is brown, very dark, brown to black.

Which industries are affected by exposure to solar radiation?

Anyone working outside in the sun can be affected by solar radiation. Outdoor work does not need to be full-time or for long periods to pose a problem. In fact, the weather can be cloudy and UV can reach workers’ skin.

Exposure to solar radiation can occur in any industry that involves outdoor working, for example:

  • agriculture and rural
  • construction, dock and maritime
  • grounds and landscape management
  • outdoor leisure
  • entertainment and professional sports
  • refuse collection and recycling
  • road working.

Which occupations are affected by solar radiation exposure?

Examples of job roles that can often be exposed to solar radiation include:

  • construction workers
  • dock and maritime workers
  • farmworkers and other rural workers
  • grounds and landscape workers
  • outdoor leisure and entertainment workers
  • painters and decorators
  • postal workers
  • professional outdoor-based sportspeople
  • railroad workers
  • refuse and recycling collectors
  • roadworkers
  • roof workers.