Joint Compound
Used extensively in building construction, joint compound is a plaster-like substance that is used to seal joints between sheets of drywall. Many construction workers who use joint compound simply refer to it as "mud." The tradesperson whose job it is to apply joint compound is usually referred to as a drywall taper.
The ready-mix form of joint compound comes in a plastic tub and is designed for fast application and is easily maintained. It can be purchased at home remodeling and hardware stores and contains ingredients such as of water, limestone, expanded perlite, ethylene-vinyl acetate polymer and attapulgite. It spreads well and is easy for even the do-it-yourselfer to apply. Mix-it-yourself compound is a little more complicated to use though somewhat less expensive. It dries out quickly and must be used within a few hours of mixing.
Joint Compound and Asbestos
In the 1960s, many companies began adding the chrysotile form of asbestos to their joint compound products. Asbestos was used to strengthen the mixture, make it thicker, and give it a longer life.
For more than a decade, drywall tapers and unsuspecting home remodelers used joint compound that contained dangerous amounts of toxic asbestos. Because joint compound is usually sanded to achieve a smooth texture, those working with the material were subject to asbestos dust and, without benefit of protective gear, probably inhaled asbestos fibers. Individuals working (or living) in the vicinity may have been exposed as well.
Georgia-Pacific, one of the major manufacturers of Ready-Mix® joint compound, began adding asbestos to their products in 1965, despite the fact that studies had already been completed which indicated the dangers of exposure to this hazardous mineral. The company did not remove asbestos from its joint compounds until 1977, so many homes and commercial buildings that used the popular Ready-Mix® may still be contaminated with asbestos.
Some joint compounds still contain trace amounts of asbestos, but consumers will not be hard-pressed to find several asbestos-free joint compounds of the market and, for their safety, should consider purchasing these products before deciding on a compound that contains asbestos. Furthermore, when ripping out drywall from older buildings, a mask or respirator should always be worn.
