Known Unknowns: Asbestos and the great death rate cover-up

There is a lot we don’t know about the presence of asbestos in UK buildings. We don’t know where it is, and we don’t know how much there is of it. Nor can we say with any confidence what condition it is in. More disturbing still, we do not know exactly how many people are dying of Asbestos Related Disease.

The absolute number of deaths

The official records suggest that approximately 5,000 people die of an Asbestos Related Disease (ARD) every year. Half of these are due to the incurable cancer, mesothelioma. The total number of UK deaths from ARD is derived from a ratio. This is because lung cancer may be caused by many different carcinogens, such as smoking tobacco, whereas mesothelioma is known to be a direct result of exposure to asbestos [i].

The Health and Safety Executive (HSE) states that the risk ratio of mesothelioma deaths to other asbestos related deaths is 1 to 1. Yet the international evidence suggests that the ratio is much higher than this [ii]. Different studies place the ratio between 2-10 times greater. The graph below shows the difference between reported and estimated asbestos deaths in the UK in 2023, using a ratio of 1:7 suggested by McCormack, Peto et al. (2013). By this estimate the total number of ‘official’ deaths from asbestos should be nearer to 20,000 per year, rather than 5,000.

Even research by the HSE’s own scientists suggest that deaths from other ARDs are eight times greater than deaths from mesothelioma [iii].

These findings are in line with research undertaken by Daniel Murphy, Professor of Lung Cancer & Mesothelioma at the University of Glasgow. Professor Murphy has conducted genetic experiments relating to the contribution of asbestos exposure to mesothelioma and to lung cancer. He has additionally examined the geographic distribution of lung cancer and mesothelioma and identified a pronounced correlation across the Scottish health boards. His findings, yet to be published, strongly challenge the HSE’s assertion of a 1:1 ratio and indicate that the contribution of asbestos to lung cancer in the UK may be vastly underestimated.

So, why does the HSE continue to state that the risk ratio of mesothelioma deaths to other asbestos related deaths is 1 to 1, when even their own published research indicates that deaths from other ARDs are much higher than deaths from mesothelioma?

The problem with the HSE’s ratio is that government policy is determined by a ‘low’ number, which is a material and deliberate underestimation. It has implications for the projected number of asbestos deaths as well as the costs and benefits of removing asbestos from buildings. Based on the higher death figures the potential costs to the state in health care and compensation for victims makes it clear that the benefits of removing asbestos far outweigh the costs of doing nothing.

In the Autumn Budget (2025) the Chancellor made the necessary provision of £14 billion to compensate the victims of the contaminated blood and postmaster scandals. This figure could be dwarfed in the long run by the real cost of compensating asbestos deaths in the UK.

Occupational deaths

There are other concerning aspects of the HSE’s official data relating to how occupational deaths are recorded and how death rates between different occupations are compared.

Firstly, occupational death rates are based on death certificates, which include the last known occupation of the deceased as well as the cause of death. However, the HSE only include occupational deaths for those aged 75 and below. If we include the deaths of those aged over 75 the figures for mesothelioma double, since most deaths relating to mesothelioma occur over the age of 75. Why does the government choose not to include these deaths in the official record?

Secondly, not all occupations are known or recorded. The last known occupation is not always an accurate reflection of how the deceased person spent most of their working life. So, in the case of a teacher that has taken early retirement or had a late career change it is the final known occupation that will be recorded. This leads to an under-reporting of occupational deaths for female teachers and nurses.

Thirdly, the statistical method which the HSE uses to compare occupational deaths is flawed. Not only does this exclude deaths over the age of 75, but it also wrongly compares the risk of death from mesothelioma between different occupations and genders.

In analysing mesothelioma risk the HSE routinely uses the Proportional Mortality Ratio (PMR) as an index of relative risk where PMR = 100 x Observed Deaths/Expected deaths. This index is deeply flawed in that the calculation of the ‘Expected’ number of deaths in all occupations can be strongly influenced by the number of deaths that occurred among men in historical occupations that were heavily exposed to asbestos such as shipbuilding, heavy engineering, construction and building trades. This serves to suppress the significance of deaths among female school and nursing staff whose occupations are not related to deaths in heavy industry.

Evidence submitted to the Work & Pensions asbestos inquiry, has suggested that mesothelioma deaths among female Primary school teachers, Teaching assistants, Nurses and Nursing auxiliaries should be compared to mesothelioma deaths among the female population as a whole. This would show that mesothelioma deaths among these female occupations are considerably higher than would be expected. This suggests that working or retired teachers, nurses and their assistants are at a much higher risk of developing mesothelioma than those in the general population and that HSE’s estimations are incorrect [iv].

Summary

Through the careful manipulation of data, and statistical slights of hand the HSE is systematically undermining the true number of deaths and the real risks of exposure to asbestos in order to maintain a policy that keeps asbestos in buildings. How many deaths does it take before the government takes notice and does something about it?

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Technical Notes

[i] Currently the ratio of mesothelioma deaths to lung cancer deaths is assumed by HSE to be 1:1. In 2023, there were 2257 mesothelioma deaths, so HSE assumed there were 2257 asbestos deaths as a result of lung cancer. This produces a total of 4514, plus 493 known asbestosis (a third asbestos disease) deaths. HSE state the total of asbestos deaths to be "more than 5000". 

“A ratio of one asbestos-related lung cancer for every mesothelioma implies there are currently around 2,500 asbestos-related lung cancer deaths each year. It is expected that there will be fewer asbestos-related lung cancers per mesothelioma in the future as a consequence of reductions in both asbestos exposure and smoking – which act together to increase the risk of lung cancer – in past decades”.

You can find this on page 3 and page 7 or the HSE statistical release (2023) https://www.hse.gov.uk/statistics/assets/docs/asbestos-related-disease.pdf 

[ii] Furuya, S.; Chimed-Ochir, O.; Takahashi, K.; David, A.; Takala, J. Global Asbestos Disaster. Int. J. Environ. Res. Public Health 2018, 15, 1000. https://doi.org/10.3390/ijerph15051000

[iii] See the HSE published meta-analysis by Dr. Darnton. The abstract reads: 

"The average mesothelioma risks (per cent of total expected mortality) per unit cumulative exposure (f/cc.yr), RM, were 0.51 for crocidolite, 0.12 for amosite, and 0.03 for the Libby mixed amphiboles cohort. Significant heterogeneity was present for cohorts classed as chrysotile, with Rm values of 0.01 for chrysotile textiles cohorts and 0.0011 for other chrysotile-exposed cohorts. Average percentage excess lung cancer risks per unit cumulative exposure, RL, were 4.3 for crocidolite and amosite combined, 0.82 for Libby."

Dividing 4.3 by 0.51 = 8.4 arrives at a figure of 21,000 deaths per year (i.e. eight times greater). You get a much higher ratio if you divide 4.3 by the 0.12 for amosite. (Note: We ignore "Libby", a mine in the USA which the UK did not import from, and we are also ignoring chrysotile, for the purpose of this comparison). Dr Darnton's paper also restates the often-quoted ratio of meso potency (500,100,1) for blue, brown and white asbestos respectively.

[iv] See Robin Howie’s written evidence provided for the Work & Pensions Committee’s inquiry into asbestos. https://committees.parliament.uk/writtenevidence/43700/pdf/