Asbestos and Lost-wax Casting 

Fireproof, durable and an excellent adhesive, asbestos is a harmful mineral fiber that forms in rocks and soil. The substance has long been used in construction projects, tools, and in a variety of household products, including makeup, art supplies, and clay pots. Recognizing it as a hazardous material, however, the U.S. banned the use of asbestos in construction and in other products in 1989. 

Now it is relatively common knowledge that the asbestos can be harmful to one’s health, leading to a wide range of life-changing and life-threatening diseases. It is the sole cause of the deadly cancer mesothelioma. It has also been linked to chronic lung conditions, including COPD and asthma as well as other types of cancer such as lung cancer, thyroid cancer and kidney cancer. While the effects of asbestos exposure can be very deadly, these effects often aren’t evident until years after exposure. The latency of this risk means that many who have worked with asbestos (or who are still unknowingly doing so) could develop severe issues much later in life. 

Asbestos Use Throughout History 

Years ago, scientists discovered asbestos was frequently used in many forms of ancient artwork. It was a component of wall murals painted by Byzantine monks as early as the 1100s. The white asbestos, or chrysolite, was used to seal in their colorful artwork, giving the pieces a smooth and shiny finish. It was also found in the walls that house these pieces of art. 

Asbestos has been found in ancient clay products, too. Because of its adhesive properties, it allowed pottery makers of long ago to shape their creations easily. It was also flame resistant when the clay was fired. In fact, today’s pottery is usually made from clay mixed with talcum, which is commonly found in close proximity to asbestos. Because of this, asbestos can still contaminate clay products to this day, and it is important for artists to be cautious about purchasing any products from outside of the U.S. 

Another form of art in which asbestos had been used was in woven cloths and tapestries. The intricate designs of ancient tablecloths, blankets and wearable items were frequently made from durable asbestos fibers. This allowed them to stay intact long after they were finished. 

Asbestos was also used for many years in lost-wax casting, a method of molding designs to develop various parts, jewelry and artwork. 

What is Lost-wax Casting? – Also Known as Investment Casting or Precision Casting 

Lost-wax casting is a method of forming objects in metals such as gold, silver or brass by first creating an original wax mold. The casting process allow artisans to bring their imaginative designs to life perfectly, because there is a high level of precision allowed. This makes lost-wax casting a go-to for industries that create meticulously shaped items which don’t allow room for flaws inevitable in free-handed work. 

The technique dates back nearly 6,000 years but it is still being used all over the world today to develop products such as jewelry, items used in dentistry (Have braces? Say, cheese!), sculptures and more. This casting is also evident in the creation of precision parts used in industries such as manufacturing. Some of the custom parts made including everything from nuts, bolts and screws to tubing, assemblies and electrical contacts (to name a few). 

Digitizing the World of Lost-wax Casting 

Computer software has changed the world of lost-wax casting, and these days, digital design and 3D printing are a mainstay in the casting process. These elements simplify the procedure from start to finish. Using CAD software, designers can create patterns used for molds. A computer allows them to conceptualize and easily shape an object in a digital interface until it’s exactly the way they envision it to be. 

This digital framework not only allows artisans to create their designs exactly the way they want them to be, but it reduces the need for labor-intensive work and associated costs. Jewelry makers now use digitization in lost-wax casting to develop prototypes of the items to be created before they’re physically molded into their intended shapes. 

Asbestos was sometimes used in the lost-wax casting process, which put individuals at risk of inhaling its fibers. The substance is easily shaped and durable, which historically made it very useful for creating molds. Jewelers employing this method of developing their products could have also exposed themselves to asbestos when soldering, leaving them at an even greater risk of developing chronic conditions. 

Richard Herr, of Wisconsin, was a sculptor who recognized (too late) the dangers of asbestos exposure all too well. Unfortunately, he died of mesothelioma in 2009 after years of using lost-wax casting to make molds for his artwork. Despite working for years as a sculptor without issue, as it commonly does, the cancer seemed to abruptly enter and end his life. 

Herr said before he passed that he was completely unaware of the long-term hazards of asbestos exposure. He willingly used the fibers in his studio without giving it a second thought. Had he known that using it in lost-wax casting would eventually cost him his life, Herr said he would have elected to use a different process altogether. This means his death could have been avoided. 

The Moral of the Story

Knowledge is power when it comes to preventing more asbestos-related tragedies. The fact that as many as 3,000 people in the U.S. alone are still losing their lives to mesothelioma means that this is still a formidable issue in this country as well as around the world where restrictions on the use of asbestos are far more relaxed. There is still a chance that people will be inadvertently exposed when using everyday items, and this should be viewed as unacceptable. 

Education concerning the dangers of asbestos exposure might help to further limit its use in art and in other industries. While the U.S. banned its use decades ago, asbestos has since been found in art supplies, jewelry, tools, parts, makeup and more in the U.S. and in other countries. Those who demo buildings with asbestos insulation must take precautions to ensure they are safeguarded against inhaling these deadly fibers and those who purchase products from overseas should be forewarned of the potential for traces of asbestos to be found. 

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Potential airborne asbestos exposures in dentistry: a comprehensive review and risk assessment, A. Michael Ierardi, Claire Mathis, Ania Urban, Neva Jacobs, Brent Finley & Shannon Gaffney (2021), Critical Reviews in Toxicology, 51:4, 301-327, DOI: 10.1080/10408444.2021.1910624.