A rigorous search through a victim’s employment history is one of the most important tasks that an asbestosis lawyer will carry out when preparing a mesothelioma claim. A case must present positive evidence to the court that, ‘on the balance of probabilities’, it was likely that a victim’s mesothelioma or asbestosis condition was due to a level of exposure to asbestos during the period of time when the claimant was employed at the defendant employer’s workplace.

In more recent times, it is hoped that a claim can be settled out of court rather than a claimant and their family having to endure a lengthy appeals process, when there may be little time left remaining to the victim.

Along with the professional construction industry, the repeated asbestos awareness campaigns by the Health & Safety Executive (HSE) reinforce the message that any building constructed or renovated up to 2000 is likely to contain asbestos insulation materials. It can mean that employer defendants cannot say for absolute certain that their workplace did not contain asbestos, especially when the period of potential exposure was during the 1960s – late 1970s peak period of asbestos imports into the UK. All asbestos was banned in the UK at the end of 1999.

Search may need to go back to the first years of employment

In an increasing number of cases there is no obvious clue as to the possible presence of asbestos in a former workplace. It is the reason why a victim or his family will call upon work colleagues to provide their accounts of working conditions and where exposure to asbestos would most likely have occurred.

A search for the source of exposure may need to go back to the first years of employment after leaving school. Different studies have shown that exposure to asbestos early in life can significantly increase the chance of developing mesothelioma, even though asbestosis symptoms may not appear until after retirement more than 40 years later.

Medical research data points to the highest incidence of malignant pleural mesothelioma is among victims under the age of 20 when they were first exposed to asbestos. There is also a strong likelihood of a greater susceptibility to other types of cancers, as well as death caused by stroke and heart disease.

There is increasing evidence to show that just a ‘one-time’ exposure early in life can be enough to trigger the later development of the terminal cancer. An early life exposure may also act as the springboard to a working lifetime of exposures at different locations, known as the ‘cumulative’ effect.

Cumulative exposure can contribute to a total risk

In one recent report published by an international group of 180 scientists from 35 countries, it was concluded that a “cumulative” exposure to asbestos can contribute to a ‘total risk’ of developing mesothelioma. Their findings are supported by other international scientific studies, including data on over 860 mesothelioma cases from more than 22,000 individual exposures across Europe, and as far afield as Australia.

The research suggests that the risk of developing mesothelioma after an initial exposure never reduces, regardless of life expectancy. In other words, the risk of developing the fatal, incurable disease of the lung linings is still at the same high level. In some cases, the risk may even increase as a result of health or environmental factors.

The study results revealed that nearly 45 per cent of pleural (lung lining) mesothelioma cases, and more than 50 per cent of peritoneal (stomach) mesothelioma cases were diagnosed at least 40 years after a first exposure. Even after 50 years, more than 13 per cent of pleural cases and 23 per cent of peritoneal cases were still being recorded. It was also found that the rate and risk of pleural mesothelioma actually increased for 45 years following a first exposure, which then appeared to advance but at a slower pace.

Over-reliance on fibre counts

The report also looked at the various criteria used in determining a diagnosis of diseases caused by asbestos, and key evidence required at a court hearing. Employer defendants can often deny liability by placing an “over-reliance on detecting asbestos bodies” and fibre counts in lung tissue as an indicator of past exposure.

Original risk levels were based upon observations of the most toxic blue ‘crocidolite’ and brown ‘amosite’ asbestos types used to manufacture insulation or fireproofing materials. As a result, they were banned in the mid 1980s, while white asbestos was considered ‘low risk’ and allowed to continue being used for a further 15 years. Today, chrysotile has been confirmed as a Class 1 cancer-causing substance without a confirmed threshold level, below which, exposure would be considered safe for human health.

Claimants have always faced a significant difficulty in establishing a former employers’ liability for preventing or minimising the potential health risk of exposure, which is believed to have caused their mesothelioma. However, as more recent research gains wider recognition, mesothelioma victims and their families will, hopefully, expect to see a more positive outcome either before or at court hearings, no matter when exposure to asbestos occurred.

More than 2,500 people now lose their lives to mesothelioma every year – up by more than 10 per cent since 2011 – according to the latest available figures from Health & Safety Executive (HSE) Annual Report, 2014.