Caroline Muspratt challenges the truth behind Aon's recent claim that skin cancer resulting from exposure to the sun could be 'the new asbestos'

Sunburn "could be the new asbestos", trumpeted insurance broker Aon recently. It fears that workers who spend a lot of their time outside, such as builders and street cleaners, could develop skin cancer and sue their employers for potentially huge sums in damages.

Employers are legally responsible for the health and safety of their workers while at work, so if they do not warn them to slap on the sunscreen, they could be at risk of liability claims in the future.

Aon has suggested that staff could claim negligence against their current or former employers, even years after the contract or job has ended. The prospect of claims stemming from an event decades ago is enough to make any employer shudder.

The broker is concerned that, a s temperatures soar this summer, builders will need to think realistically about protecting their employees from the potential cancerous effects of working out in the sun all day.

The suggestion is that by including sun protection in their health and safety policy, they will be able to defend more effectively a claim if a former employee tries to prove negligence on the part of his employer for his illness.

Potentially, Aon is right. In an increasingly litigious world, there are some people who would sue over anything - and, to be fair, many workers are indeed at risk from over-exposure to the sun.

Skin cancer is the most common form of cancer in the UK and the main risk factor is exposure to the sun's ultraviolet rays. There are estimated to be more than 70,000 new cases of skin cancer in the UK each year.

Cancer Research UK's SunSmart campaign observes that, on average, people who work outdoors receive three to four times more ultraviolet exposure each year than people who work indoors. This cumulative exposure puts outdoor workers at greater risk of non-melanoma skin cancers, which are the most common form of skin cancer in the UK.

While there is no doubt that people who work outside are at risk, there are crucial differences, from an insurance perspective, between skin cancer and asbestos-related illnesses.

Someone suffering from mesothelioma, who has been exposed to significant amounts of asbestos dust by different employers, cannot prove which instance of exposure caused the disease.

However, it can almost certainly be assumed that a worker came into contact with the asbestos through their job, and not merely by going about their daily life.

Sunburn on the other hand is much more difficult to blame on an employer - if not impossible. Someone who has spent a couple of years working as a builder would have great difficulty in blaming their boss for skin cancer.

He would have to prove that the sunburn that developed into the disease had been sustained at work, and not while sunbathing at home in the garden or during that two-week holiday in Menorca in 1996.

And what about personal responsibility? While employers should encourage workers to cover up in the sun and use sunscreen, it would not be easy to enforce the rule. If a person who knows he is going to be outside all day chooses not to use suntan lotion, he should be aware that he is more at risk.

Simon Collings, head of the employers' liability practice at Marsh, has similar thoughts, noting that, unlike asbestos, exposure to sunlight will not be limited to the workplace and there is likely to be a significant amount of contributory negligence should an employee contract skin cancer.

Research has suggested that children who suffer sunburn very early in life are more likely to develop the most dangerous form of skin cancer as adults. So there is perhaps as much chance of seeing cancer sufferers suing their parents for not keeping them in the shade as babies.

Employers should certainly be aware of their responsibility to their staff when they work outside in the sun. But, while claims from asbestos are expected to cost the UK as much as £20bn over the next few decades, it is unlikely that claims over skin cancer, if any, will reach these proportions.

The insurance industry does need to keep looking ahead and try to predict the "next big thing", but calling these issues - whether it is sunburn, lead in paint or toxic mould - "the new asbestos" is little more than scare mongering. IT

' Caroline Muspratt is insurance correspondent for the Daily Telegraph