You may think asbestos is a thing of the past — the sort of thing that's found in public buildings from the 1970s. And you would be right. But it's by no means the whole truth, because asbestos fibers can also hide in places where nobody would expect them, and where they are hardly visible. 

At the beginning of November,the Association of German Engineers (VDI) therefore adopted a new, stricter directive. It stipulates that companies must always sample building materials for asbestos in suspected cases. This is intended to protect the workers, but also to prevent asbestos-contaminated building rubble from being fed back into recycling processes undetected and thus being turned into new building material.  

Careful when renovating!

Even during a simple renovation in your own home, dangerous concentrations of asbestos fibers can quickly get into the air you breathe. 

It can happen when you replace the glass in an old window or when you install a whole new window or doorframe. Fibers can be released when breaking off old bathroom tiles or preparing a wall before you lay electrical cables.

Even when putting in a new hardwood floor it's important to think about the risks of asbestos, because it can cause a deadly cancer called mesothelioma.And it's a good idea to know what you're looking for.

"Every specialist knows corrugated asbestos slabs, which can still be found on many roof coverings today. They are easy for anyone to identify, even if they are only halfway trained," says Frank Jansen of the VDI.

But it's not always that simple. 

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Mortar, spackling paste, putties

After all, who would suspect that asbestos can hide in the mortar under old tiles in the bathroom, in plaster on a wall, between joints in a drywall ceiling, or in and under an old floor covering? Unfortunately, hardly anyone at all — not even many skilled workers, says Jansen, a civil engineer.

It was only 10 years ago that experts became aware of the fact that asbestos fibers had been added to mortar powders, fillers, plasters and spackling paste for decades. 

Asbestos fibers may only make up a tiny percent of what goes into those materials. But if you had to process a wall with a grinding machine — for example, to lay new tiles or cut the wall with an angle grinder to prepare it for new electrical wiring — asbestos fibers would be released into the air in life-threatening concentrations.

The dust generated during such work is so fine that it penetrates everything. If it contains asbestos fibers, even a small amount is sufficient to seriously damage the lungs. 

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Many craftsmen do not know the danger

In 2015, Jansen published a discussion paper on the problem with the VDI and a German industrial umbrella organization that sets the standards for the handling of hazardous substances, the Gesamtverband Schadstoffsanierung. Jansen says even he wasn't aware of the full extent of the problem of asbestos contamination at first.

"I did an apprenticeship as a tiler before my studies. When I then came into contact with this topic through my work at the VDI, my first thought was, 'Ouch! This danger basically lurks in any building that was erected before the turn of the millennium,'" says Jansen. "And that doesn't even include the houses that were renovated."

Although lung cancer caused by asbestos was recognized as an occupational disease in Germany as early as 1942, it was only in 1995 that the substance was banned in the country. Ten years later it was banned throughout Europe. 

Perhaps that's why it took so long for experts to become aware of the less visible asbestos hidden in building materials.

Deadly. Even decades later

"The occupational safety experts first looked at the asbestos that was frequently and visibly used in building materials or other such products," recalls Thomas Kuhlbusch, group leader of the Hazardous Materials Management Division at the Federal Institute for Occupational Safety and Health (BAUA).

"Those included Eternit panels, facade claddings, roofs built with asbestos materials and also fire protection boards and textiles," says Kuhlbusch. "But in the beginning, products that only had small amounts of asbestos, or in which the asbestos was not visible, were less obvious to experts."

In addition, it can take a very long time for workers exposed to asbestos dust to fall ill. 

"We now have cases, where people have died 40 years after their exposure to asbestos fibers," says Kuhlbusch. 

The tiny fibers persist in the alveoli, the tiny air sacs in the lungs, for a very long time. They are not broken down and can still cause inflammation decades later. 

"Asbestos is still a frequent cause of work-related illnesses and deaths," says Kuhlbusch. 

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How big is the risk?

Some researchers say asbestos is a naturally occurring mineral that can be found in the air all around us — all the time. You could call this background levels of asbestos.

So whether you're a craftsman, tenant or real estate owner, it's important to know how to recognize and deal with it, says Kuhlbusch, a chemist by trade. 

But overstating the risk does not help either.

"Studies suggest that 75 to 130 fibers are present per cubic meter of air," says Kuhlbusch. We inhale these fibers all the time. But not everyone gets lung cancer as a result of asbestos, he says.

And what if those studies are wrong?

Stephan Baumann is a pollutant expert at BAFOB in Switzerland.

BAFOB runs tests on air quality, and Baumann says their tests suggest asbestos fibers are not as ubiquitous as some people think. 

Baumann says that final measurements carried out by his company after completed asbestos decontaminations do not show high background levels of the mineral. 

The toxicologist tells DW that 90 to 95 percent of their tests are completed without any fibers found. 

It is possible that the fibers in the air outside also stem from car and train traffic. Until the late 1980s, brake linings contained high levels of between 50 and 90 percent asbestos. Especially at intersections, where many cars brake, high fibre concentrations could be measured in the past. Although brake linings containing asbestos are banned in the EU today, it cannot be ruled out that there are still contaminated brake linings on the market. 

No reason for panic

It's said that a single asbestos fiber is sufficient to cause cancer. But that doesn't mean that every fiber inhaled will inevitably lead to cancer.

Kuhlbusch compares the risk to a huge wall behind which there's a thin water pipe: "If I knock a nail into the wall," he asks, "what is the probability that I will hit the water pipe?"

The risk of cancer increases with the concentration of fibers in the air and with the length of time a person is exposed to the asbestos. So the less you come into contact with asbestos, the better. 

If you see asbestos, you should avoid it.

And with the right measures — like using a professional vacuum to suck up the hazardous dust — you can effectively reduce the risk.