Almost any building material over 30 years of age may contain or be attached to some type of asbestos containing product.īecause of factors including the increasing human life span, better medical diagnostics and the myriad of products that have contained (or still do) contain asbestos, diagnoses of asbestos diseases are expected to increase for decades to come. Immediately before and after World War II, brakes, clutches, building plasters, cements, shingles, insulation, drywall joint compounds and textured paints commonly contained asbestos. Asbestos was used in paper production in order to obtain a higher grade of paper with a lower grade of pulp. For example, asbestos was used as a filler in many plastics and adhesives (glues). Sadly, in the United States, asbestos use increased dramatically as other properties of asbestos were recognized. England then began passing laws designed to protect English workers. Soon thereafter, an English study showed that 25% of asbestos workers had signs of lung disease. In the mid-1920's, an English doctor made what many believe was the first diagnosis of asbestosis. During the course of the next two decades, physicians noted that asbestos workers had uncommonly high levels of illness and disease. An English physician performing a post-mortem on a man who worked with asbestos discovered asbestos fibers in the mans lungs. It was not until the early 1900's that knowledge regarding the dangerous propensities of asbestos began to resurface. Asbestos then began to be used as insulation for steam pipes, turbines, boilers, kilns, ovens, and other high-temperature products. Asbestos was used in very limited ways for many hundreds of years with its popularity increasing during the Industrial Revolution beginning in the late-1800's. Pliny wrote, "Asbestos looks like alum and is completely fire-proof it also resists all magic potions, especially those concocted by the Magi." Both Pliny and the ancient Greek geographer Strabo observed the "sickness of the lungs" in the slaves that wove asbestos into cloth.Īsbestos references can be found in texts from many different cultures throughout recorded history. 77, Pliny the Elder published the first encyclopedia, Natural History. It was this property that first was recognized and used in ancient times for everlasting lamp wicks. The type of asbestos most people commonly recognize is generally made up of fiber bundles which easily separate into long, thick fibers. Actinolite appears as dark green crystals or fibrous aggregates. Actinolite has a chemical formula that is similar to tremolite, but actinolite contains more iron in relation to magnesium than does tremolite. Bitotite mica schist, hornblende schist, garnet mica schist, and talc schist are some examples. Schists are metamorphic rocks usually named by the main mineral from which they are formed. Tremolite can be found in various types of schists. Tremolite is a calcium, magnesium, iron silicate and is white to grayish green. Anthophyllite is a magnesium iron silicate hydroxide. It is associated with talc and other minerals. Anthophyllite ranges in color from white to gray to brown. The other asbestos types, all in the amphibole group, are anthophyllite, tremolite, and actinolite. Crocidolite is a sodium iron magnesium silicate. Crocidolite, a member of the amphibole asbestos family, takes the form of blue, straight fibers. Amosite is a member of the amphibole asbestos family. Amosite asbestos is made up of straight fibers containing iron and magnesium. ![]() ![]() Chrysotile is a member of the serpentine group and is a magnesium silicate. The three most common types of fibers are chrysotile (white asbestos), amosite (brown or gray asbestos) and crocidolite (Riebeckite).Ĭhrysotile asbestos is a white curly fiber and accounts for 90% of asbestos in products. Amphibole asbestos has a chain-like structure. Serpentine asbestos develops in a layered form. ![]() Asbestos can be divided into two basic groups, serpentine and amphibole, which differ in their physical characteristics. ![]() It is composed of silicon, oxygen, hydrogen, and several different metals. The word asbestos means inextinguishable.Īsbestos is the generic name for six naturally occurring minerals. The Greeks recognized the fireproof qualities of asbestos, while recognizing the harmful effects on asbestos workers. The mineral asbestos gets its name from the Ancient Greeks. Mesothelioma is caused by inhaling or ingesting asbestos fibers.
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