Long before the Great Pyramids were built, asbestos was being mined. Evidence from archaeological studies shows us Stone Age ceramic pots strengthened with asbestos, it shows us durable asbestos cloth spun by the ancient Greeks and long-lasting candle wicks from the Roman era.

One of the great Roman writers, Pliny the Elder, records the use of an incombustible fabric called abestinon. And from other writings of that era, detrimental health was being attributed to exposure to asbestos, particularly recording early death due to lung ailments. Really? ...this was 2000 years ago!

The word "asbestos" was first used by us in the 1600s. Before that, we had called it “amiant”, from the French “amiante” and Portugese “amianto” which was a derivative of the Greek “amiantos”, meaning undefiled or inextinguishable, presumably based on its fire resistant properties.

Towards the end of the 19th century, asbestos began its 100 year sprint. Health warnings were ignored and demand for better insulating and heat-resistant products in almost every industry the world over meant that it became probably one of the most sought-after commodities.

In 1898, a British factory inspector spoke out strongly against the use of asbestos but through much of the 20th century it continued to be used widely in manufacturing and construction. In 1900 an asbestos worker who had supposedly died of bronchitis was found to have heavy scarring in his lungs. Health reports on cases of asbestos workers continued to be issued and asbestos poisoning became an important topic in the British Medical Journal. The first medical diagnosis of asbestos poisoning was issued in the early 1920s to a young factory worker who was suffering and died in 1924 aged 33. The medical term 'asbestosis' was first used in 1927 to describe the awful condition tearing through its victims, then the link to the dreaded cancer was first suspected in the early 1930s, a break-through discovery reinforced by further research much later in the 1960s. 1931 had seen the release of the Asbestos Industry Regulations, then through the ensuing decades, numerous articles and standards were published which included the 1968 BOHS Safe Hygiene Standard, the new 1969 Asbestos Regulations, then the Great Britain Asbestos Survey of 1971 which led onto the first successful asbestos related claim being won in 1972. Then between the mid 1980s to the late ‘90s, legislation in the UK and many countries was tightening which culminated in a complete ban on all use of asbestos in any form. That was it; the sprint was over.

Now, despite it being illegal to use for over 30 years, it is reckoned that at least 100,000 people each year are still dying from asbestos related diseases, most commonly asbestosis (scarring of the lungs due to asbestos inhalation) and mesothelioma (a type of cancer). This is the legacy of the asbestos era, with the consequences of exposure sometimes taking decades to symptomise. Additionally, maintenance and renovation of old buildings still requires handling and removal of asbestos which presents a risk that can never be completely eliminated, even when best possible practice is observed in its handling and disposal. Many buildings constructed pre-1980 would still contain asbestos in one form or another.

Asbestos is a collective name for a family of six types of naturally occurring silicate minerals that are found in certain rock formations. These fall into two groups, serpentine and amphibole. Serpentine, which accounts for about 95% of commercially used asbestos and known commonly as white asbestos or chrysotile, is made up of flexible, curved fibres. Conversely, amphibole fibres are straight and rigid, normally brittle and needle-shaped. Amphibole has five sub-types: Crocidolite (known as blue asbestos), Amosite (known as brown asbestos), Actinolite, Anthophyllite and Tremolite.

Typical in form and structure of all silicate minerals, asbestos has the appearance of shiny rock from a distance but close up you see its long, thin fibrous crystals, each made up of microscopic fibrils that are easily released into the atmosphere by abrasion or similar processes. When disturbed, asbestos fibres can remain suspended in the air for many hours. (A "fibre" is defined as a particle in excess of 1µm in length with a length/width ratio of at least 3:1. Asbestos fibres can be straight or curled and although they are often 5-10µm in length, they can be as short as 0.1µm (100nm)). 

 

The probability of any product with asbestos content releasing its fibres is dependent upon its friability. Friable means that a material can be crumbled, pulverised, or reduced to powder by hand and consequently is likely to shed fibres. All forms of asbestos have a tendency to break down into dust, particularly insulating materials. Some are more stable, such as asbestos-containing concrete products which are often considered safe as long as they are not disturbed.

 

Exposure to asbestos is primarily through inhalation and ingestion of fibres. Because asbestos has been so widely used, most people are exposed to some low levels in the air they breathe. The tiny fibres float in the air, stick to clothes and are easily inhaled or swallowed. 

 

Fibres breathed in are deposited in the passages of the lungs and on the cells that make up the lungs. Most fibres will be carried away in mucous to the throat where they are swallowed into the stomach. This process usually takes place within a few hours, but fibres that are deposited in the deepest parts of the lung take longer to be removed, some can remain in place for many years and some may never be removed.

 

Fibres that are swallowed (either those present in water or those that are moved to the throat from lungs) nearly all pass along the intestines within a few days and are excreted in the faeces. A small quantity may penetrate the stomach lining or intestines and enter the bloodstream, some become trapped in other tissues and some are removed in urine.

 

Although asbestos fibres are a health risk, the risk of asbestos-related disease depends upon the level of exposure. At very low exposure levels, health risks are not normally considered serious. High exposure levels have shown to cause asbestosis (a fibrous scarring of the lungs), lung cancer (bronchogenic carcinoma), and mesothelioma (a cancer of the lining of the chest or abdominal cavity). However, we speak of low and high exposures but the quantity or concentration of fibres a person must inhale or ingest to develop disease is uncertain.

 

There are a number of ways that asbestos can be identified. Most commonly, the crystalline structure can be identified by light scattering but a method is also used that takes advantage of its magnetic susceptibility, an almost unique property for a fibrous mineral. More recently, Fourier Transform Infrared (FTIR) spectroscopy is being used which is highly accurate in mineral identification.

 

Now, thirty something years on, someone somewhere has taken up a case in favour of asbestos. Progressive research in an emerging field of scientific study into carbon sequestration has explored the use of mineral wastes, using mining waste materials from nickel, copper, diamond and platinum, but none with such apparent potential as asbestos. Chrysotile, the common type of asbestos, has been found to chemically react with CO2, producing ecologically stable Magnesium Carbonate. Like all types of asbestos, chrysotile has a large surface area affording greater opportunity for chemical reaction compared to most other minerals.

 

Whether we can find a way to safely extract and handle asbestos commercially for it to be of environmental benefit remains to be seen - and even then, is it of sufficient benefit to become viable? 

 

One thing we can be sure of, health comes first and if there is ever a question or doubt over what may appear to be asbestos, we can be thankful for stringent regulations, professional teams and suitable equipment to ensure its safe removal and disposal.

 

Work right. Breathe right. Feel great.