The long string of studies and policies that eventually ended in the ban of lead-based house paint began in the early 20th century. There began to be concerns about the potentially harmful effects on workers in the paint industry. The paint industry worked with public health officials to make work practices safer and succeeded in minimizing lead poisoning in paint industry workers but took no steps to end the use of lead paint. During this time, some European nations banned lead in paint to help protect painters. However, in the U.S., opposition from painters prevented such a ban from being put into effect.

Beginning in the 1920s, some children were diagnosed with “pica,” or an unusually strong desire to eat nonfood substances. These children often chewed on their toys or the side of their cribs and therefore were exposed to the lead paint often used on these items. At first, doctors merely recommended that the children be closely supervised and prevented from chewing on cribs and toys. However, in the 1930s, lead paint began to be eliminated from cribs, toys, and other products commonly used by children. In the 1940s, several medical journals reported that this effort had been successful.

In 1948, the lead paint issue was brought up again when public health investigators in Baltimore detected risks to children from peeling and/or chipping lead-based interior paint in homes. In 1951, Baltimore became the first U.S. city to ban lead paint.

In 1955, the American Standards Association and the American Academy of Pediatrics, working together, developed the first national restriction on lead in paint; that paint should not contain more than 1% lead. Paints containing more than this amount of lead were required to have a warning indicating that they should not be used on surfaces accessible to children. Finally, in 1978, the United States banned lead in house paint altogether.