Question: what do the buildings in the images below have in common?
Answer: they all contain asbestos!
As with concrete, both the applications and risks of asbestos have been known for a surprisingly long time - pots and cooking utensils dating back to 2400 BC have been discovered and Pliny the Elder noted in 1st century AD that slaves who came into contact with asbestos were more likely to become ill.[1]
Throughout the Middle Ages there are numerous tales surrounding a mysterious fire-proof material that was often believed to be the skin of a salamander (although the legendary explorer Marco Polo realised this substance was a mineral mined from the Earth).[2]
The term asbestos refers to a group of six naturally occurring silicate minerals that vary in colour, but all have a fibrous nature. The most common type of asbestos is chrysotile – often referred to as white asbestos. [3]
These minerals have a wealth of beneficial properties; particularly being heat and fire resistant. In the 19th century, with the advent of steam powered machinery and associated increase in the need for insulating and fire-proof materials, the manufacture of asbestos containing materials increased dramatically. Some even dubbed asbestos a “magic mineral”.
But soon after a worrying trend became apparent – the workers employed in textile factories that manufactured asbestos containing materials dying young, with remains of asbestos fibres found in their lungs. This led to a new cause of death (asbestosis) to be recognised. However, despite the introduction of government regulation to improve the working conditions of those involved in the manufacture of asbestos containing materials, asbestos continued to be widely used during the 1930s to the 1950s. [4]
However, during the 1950s a further terrifying discovery was made about the health risks posed to those working directly with asbestos – they were around 10 times more likely to develop lung cancer than the general population. Even worse, in 1960 cases of this cancer (mesothelioma) were found at an increased rate in people who lived in the neighbourhood of asbestos mines but did not work directly with the material. This demonstrated that even indirect contact with asbestos could have devastating health implications. Though much stricter regulations and complete bans on asbestos in many countries followed, asbestos had already been widely used in construction for decades.
Mesothelioma, a cancer found in the mesothelial tissue that surrounds several vital organs including the lungs, has an incredibly poor prognosis. Only 10% of those diagnosed survive for 5 years and, at present, due to large part to how difficult it is to distinguish the symptoms of mesothelioma from other conditions such as emphysema and pneumonia.[5]
So why is asbestos carcinogenic? One theory is that asbestos fibres are narrow enough to escape the action of the cilia and other mechanisms that the lungs have to protect themselves from contamination, meaning that asbestos fibres can build up in the lungs[6]. However, because the asbestos fibres are longer than the white blood cells (macrophages) that would typically engulf bacteria and other harmful microorganisms cannot be engulfed and broken down by the white blood cells. This sets off a variety of harmful inflammatory responses that culminate in the formation of cancerous cells.[7]
Today, it is estimated that approximately 107,000 people die each year from asbestos exposure[8] and that around 10,000 people have died from working in UK school buildings containing the material. A damning statistic that puts the UK amongst the worst in the world for asbestos related deaths in schools[9].
Photographs taken by the wonderful Chrissy Osborne
[1] https://www.asbestos.com/asbestos/history/
[2] https://www.wired.com/2014/08/fantastically-wrong-homicidal-salamander/
[3] https://www.mesothelioma.com/asbestos-exposure/what-is-asbestos/
[4] https://blogs.imperial.ac.uk/imperial-medicine/2018/02/02/the-asbestos-story-a-tale-of-public-health-and-politics/
[5] https://www.mesotheliomahope.com/mesothelioma/diagnosis/misdiagnosis/#:~:text=Malignant%20mesothelioma%20is%20often%20misdiagnosed,a%20history%20of%20asbestos%20exposure.
[6] Paul A. Baron Ph.D., Chapter FI, NIOSH Manual of Analytical Methods (NMAM), 5th Edition
[7] Fiorilla I, Martinotti S, Todesco AM, Bonsignore G, Cavaletto M, Patrone M, Ranzato E, Audrito V. Chronic Inflammation, Oxidative Stress and Metabolic Plasticity: Three Players Driving the Pro-Tumorigenic Microenvironment in Malignant Mesothelioma. Cells. 2023 Aug 11;12(16):2048. doi: 10.3390/cells12162048. PMID: 37626858; PMCID: PMC10453755.
[8] https://www.compoundchem.com/2018/08/14/asbestos/
[9] https://www.asbestosjustice.co.uk/case_study/an-update-on-asbestos-in-schools/