1 The first safety matches, patented in Sweden in 1855, were developed to correct two problems associated with phosphorus friction matches, in common use since 1836: spontaneous combustion, and necrosis of the jawbone among factory workers exposed to phosphorus fumes. By 1875, several kinds of safety matches were available, all of which required a special striking surface for ignition and were made without phosphorus, or with a nontoxic form of it. Two of the most well-known brands were the American Safety Parlor Match, made in Erie, Pennsylvania, and the Hendrickson and Leigh Safety Match, made in Trenton, New Jersey. Because these products often created a dangerous explosion of sparks, and were easily damaged by moisture, toxic phosphorus matches remained in wide use until 1911 (Manchester, 35–36, 46–47, 57–58, 71–75).