The Copșa Mică works were two factories in the Transylvanian town of Copșa Mică, Sibiu County, Romania. Sometra, established in 1939, produced non-ferrous metals, particularly zinc and lead, through smelting; production has been suspended since 2009. Carbosin, dating to 1935, specialized in carbon black, and shut down in 1993. The two were the town's principal employers, but combined, they made it among the most polluted places in Eastern Europe. Soot from Carbosin encased Copșa Mică in a black covering, while metals from Sometra suffused the air, water and soil, leading to serious health effects on surrounding residents, vegetation and wildlife. The factories Sometra Sometra was founded as a private firm in 1939 for the purpose of zinc smelting. Initially, it had three distillation furnaces, with five more added in 1948, the year it was nationalized by the new communist regime. Its initial capacity was 3000 tons of zinc per year, expanded to 4000 tons in 1946. Between 1950 and 1960, capacity was gradually expanded to 28,000 tons a year. In 1955, a unit for producing sulfuric acid was inaugurated. The unit was expanded in 1966, a year that also saw the introduction of a system for agglomerating concentrates of zinc and lead. This was the culmination of a four-year program of thorough restructuring and modernization, with the new equipment having a capacity of 30,000 tons of zinc and 20,000 tons of lead bullion per year. The 1967-1970 period saw the introduction of an electrolytic lead refining system (capacity 24,000 tons a year); a unit for extracting metallic bismuth for technical and pharmaceutical use from anode sludge, as well as gold and silver alloys and antimony slag; a unit for zinc sulfate production; a unit for zinc and ammonium chloride production; and an air preheater. Capacity was doubled between 1975 and 1984. A second zinc and lead extraction unit, with annual capacities of 30,000 tons (zinc) and 20,000 tons (lead) went online, as well as two thermal zinc refineries and greater cadmium refining. In 1983, metallic antimony production began by extracting the metal from slag, along with sodium thioantimoniate and stibnite. In 1984, a second blast furnace began operation, so that the old components built from 1939 to 1957 were retired. Between 1985 and 1989, zinc powder production began and a system for collecting residual gases was put in place. In 1988, a 250 m high chimney was built. By 1989,