Asbestos, a hazardous mineral that is the only confirmed cause of the deadly form of cancer called mesothelioma, was a common ingredient used to make thousands of products until the early 1980s. An example of these products is masonry fill that is poured in between the cinder blocks that make up walls and other structures. The masonry fill provides insulation. Asbestos was used in the fill because of its heat resistance, durability, and low cost.
Companies continue to produce masonry fill that contained asbestos even after the dangers were known because they could not find a substitute that was as cheap and easy to use. Sometimes vermiculite, another mineral, was used in the fill, but the vermiculite was often contaminated with asbestos, making it just as dangerous. This was the case with Zonolite, a brand of vermiculite insulation and masonry fill made by W.R. Grace and Company.
Anyone working with masonry fill is at risk for inhaling or swallowing the tiny asbestos fibers that get in the air. Once inside the body these fibers can become embedded in the lining around vital organs like the lungs, heart, or abdomen. The body attempts and fails to repair the damage that the fibers cause and mesothelioma develops.