The company suffered heavy financial losses in the early and mid-1980s . Beginning on September 29 , 1982 , seven people died after taking the painkiller Tylenol . Investigators discovered that someone had tampered with the product , lacing it with potassium cyanide . Terrified parents nationwide refused to allow their children to celebrate Halloween the following month , and sales of costumes plummeted and did not recover for several years . Ben Cooper , Inc. formed the Halloween Celebration Committee along with eight other manufacturers of Halloween costumes , masks , makeup , and accessories and ( in cooperation with the Toy Manufacturers of America ) published the booklet " 13 Great Ways to Celebrate Halloween " in order to reassure parents and help stimulate interest in the holiday again . Despite this setback , in 1984 the firm was still the largest supplier of Halloween costumes in the United States . The company recovered around 1987 , as total sales of accessories , costumes , and makeup rose at an annual rate of 20 percent a year
seven people died
Chicago Tylenol murders
Ben Cooper, Inc.