THE UK government could face a flood of compensation claims from women who develop breast cancer after working night shift, lawyers warned yesterday.
It follows a landmark ruling involving the Danish government, which has started paying damages to women suffering from cancer after long spells working nights.
The Danish authorities acted after a finding by the International Agency for Research on Cancer (IARC), an arm of the UN's World Health Organisation, which found that night shifts probably increase the risk of developing cancer.
For years, there has been growing evidence that night shifts are bad for workers' health, with symptoms including disturbed sleep, fatigue, digestive problems and a greater risk of accidents at work.
But these are the first government payments to women who have developed cancer after long periods of antisocial hours.
Bruce Caldow, a partner in employment law with Harper Macleod solicitors, said the case opened up the issues of whether working nights caused lasting damage and if staff were aware of the risks.
"I'm certain that lawyers in Scotland and the rest of the UK will carefully scrutinise these written judgments to see whether legal action could be taken," he said.
Rory McPherson, an employment lawyer with Thompsons solicitors, said employers could fall foul of the law.
"The UK government and the Health and Safety Executive should urgently look at the medical evidence to see what guidance can be given to employers and employees," he added.
Almost 40 Danish women have won compensation, including Ulla Mahnkopf, who spent 30 years as a flight attendant for the Scandinavian airline SAS.
She said "I had no idea. But when you think back now, I can see that when I stopped flying, it was like coming out of a shell – I had been living in there because of jet lag and I can see now I had a totally different life."
Dr Vincent Cogliano, of the IARC, said the agency reached its conclusion about night shifts after looking at studies of both humans and animals.
One of the reports, published in the Journal of the National Cancer Institute, showed a 36 per cent greater risk of breast cancer for women who had worked night shifts for more than 30 years, compared with women who had not.
Dr Cogliano said there was evidence to support the hypothesis that alterations in sleep patterns could suppress the production of melatonin, a hormone secreted by the brain.
"Melatonin has some beneficial effects in preventing some of the steps leading to cancer," he said. "The level of evidence is really no different than it might be for an industrial chemical."
In the UK, it is estimated about 20 per cent of the workforce work night shifts.
The recent research was based on the incidence of breast cancer among nurses and flight attendants, backed by animal studies which showed that constant light, dim light at night or simulated jet lag substantially boosted tumour development.