Many of the traditional sources of lead in the United States have been minimized by a variety of federal laws, enacted from 1978 on, banning lead paint and glazes and leaded gasolines, and prohibiting the use of lead pipes in construction and the use of lead solder in food and soda cans. Workplace exposure has been regulated by laws requiring the use of respirators, dust suppressors, and proper ventilation, and lead waste disposal guidelines have been developed. Continuing sources of environmental lead include water that has passed through old lead pipes, paint in older buildings, lead improperly disposed of in public landfills, and industrial sources such as mining, smelting, and recycling processes necessary to produce lead for batteries and other products.
Young children are usually exposed by ingesting paint chips containing lead. This source is most prevalent in poor areas where old, peeling lead-containing paint and plaster in rundown housing is common. Inadequately nourished or emotionally deprived children who resort to chewing inedible things (a condition known as pica) are most susceptible.