Although zinc in the environment is generally considered to be beneficial or benign, excessive amounts can cause deterioration of environmental quality and toxicity problems for some plants and animals. High amounts of zinc in the environment are often associated with zinc production and consumption and to the use and disposal of zinc-containing products. To obtain some upper limit parameters on the historical quantities of zinc that may have entered the U.S. environment from anthropogenic sources, the Bureau of Mines conducted a materials flow study of zinc from the earliest beginning of the domestic industry through 1990 and for the year 1989. In the 1850-1990 period, U.S. mines and smelters produced 15 and 20 pct, respectively, of world output, and U.S. zinc consumption accounted for about one-fourth of the world total. Maximum zinc losses into the environment related to the production, consumption, and disposal of end use products total about 63 million tons. Dissipative uses and landfill disposal have accounted for about 73 pct of the potential zinc losses to the environment, followed by mining and smelting, 22 pct, and manufacturing, 5 pct. At the end of 1990, contained zinc in useful endproducts in the United States was estimated to be about 23 million tons. In 1989 slightly more than 1 million metric tons of zinc in new zinc-containing products was added to the domestic pool of zinc in use and an estimated 0.9 million tons was dissipated and discarded, indicating only small net gains to the zinc pool in use annually.