Outdoor workers at heightened risk of skin cancer



Construction workers' desire for a summer sun tan could be putting them at heightened risk of developing skin cancer, new research has shown.

A new study led by researchers from Heriot-Watt University and the Institute of Occupational Medicine in Edinburgh, funded by the Institution of Occupational Safety and Health (IOSH), has for the first time measured UV exposure amongst construction workers in the UK, who during summer are at risk of excessive exposure due to the nature of their work.

There is currently limited research to understand the barriers to workers adopting sun-safe behaviours and the association this may have with vitamin D production.

Our desire for a tan is stopping us from taking proper care to protect our skin from the damaging effects of the UV radiation in sunlight.

Professor John Cherrie, Principal Investigator on the research from Heriot-Watt University.

Researchers investigated whether an intervention in the form of a combination of short messages delivered to the smartphones of construction workers, along with appropriate organisational support, can keep workers safe and healthy. The messages attempted to influence workers to reduce exposure to UV radiation in summer and to increase intake of vitamin D in winter when sun exposure cannot maintain a healthy amount.

The research examined the concentration of vitamin D in blood samples and measured UV radiation exposure of individual workers with wearable electronic sensors.

The study found almost half of outdoor workers on construction sites had insufficient vitamin D during the winter.

However, during the summer the desire to get a sun tan remained high among workers, with many exposing themselves to UV radiation deliberately, increasing their risk of developing non-melanoma skin cancer.

Professor John Cherrie, Principal Investigator on the research from Heriot-Watt University, said: “In Britain, we love the sun and having a sun tan but unprotected exposure to the summer sun can cause irreversible damage to our skin and ultimately may lead to a diagnosis of skin cancer.

“Every year there are more than 3,000 cases of skin cancer caused by outdoor work in construction and other industries. Our desire for a tan is stopping us from taking proper care to protect our skin from the damaging effects of the UV radiation in sunlight.”

Nine sites throughout Central Scotland and Greater London were included in the study. Recruitment was for three waves of data collection – two low UV exposure periods during the winter and one high UV exposure period during the summer, with each study period lasting 21 days.  

During the high UV period participants were issued with a UV wearable sensor mounted on the rear of their hard hat. These sensors logged UV measurements throughout a working day.

UV exposure was measured through standard erythemal dose (SED), which provides a measure of exposure that is independent of skin type, over an 8-hour day. The International Commission on Non-ionising Radiation recommends a limit on daily exposures for a person with light coloured skin to 0.3 SED per day; above 2 SED in a day they are at risk of getting sunburn.

During the winter study periods vitamin D levels in the group receiving the short message intervention were significantly higher after the intervention: from 48% with sufficient levels to 88% in the first winter period and from 52% to 70% in the second.

This suggests daily information and availability of a dietary supplement is likely to increase vitamin D levels during periods when UV is too low to be synthesised naturally.

However, during the summer workers who predominantly worked outdoors were exposed to an average 2 SED and those who worked partly indoors and partly outdoors were exposed to 0.69 SED. In the outdoor workers around 40% of the daily exposures exceeded 2 SED while about 12% of the exposures for the indoor workers were above 2 SED.

These levels, over a working lifetime, could significantly increase the risk of non-melanoma skin cancer. 

The short messages during the summer wave did not influence workers to take protective measures, which the researchers attributed to the widespread misconception that it is healthy to have a sun tan.

The study team included researchers from Heriot-Watt University, the University of Edinburgh and the Institute of Occupational Medicine and was funded by the Institution of Occupational Safety and Health.

The report, 'Nudging construction workers towards safer behaviour', is available here

In 2019, Heriot-Watt is celebrating its Year of Health, a calendar of engagement that spans schools, communities, businesses and government. Throughout the year, the campaign will highlight the university's research and the ground-breaking discoveries that are helping drive innovations in healthcare, diagnosis and treatment.