China makes more toys than any other country in the world, producing a whopping 75 percent of them. But laborers in many of the factories work six- or seven-day weeks of long hours, and few female workers receive maternity leave or child care. Toy production also involves close contact with dangerous chemicals, which results in alarmingly high levels of occupational disease and work-related injuries. German photographer Michael Wolf visited five toy factories around mainland China to document what workers' lives are like as they make all those toys. (20 PHOTOS)