Lead poisoning – Symptoms and causes – Mayo Clinic

Most lead poisoning in children results from eating chips of deteriorating lead-based paint. Water pipes and imported canned goods. Lead pipes, brass plumbing fixtures and copper pipes soldered with lead can release lead particles into tap water. Lead solder in food cans, banned in the United States, is still used in some countries.

https://www.mayoclinic.org/diseases-conditions/lead-poisoning/symptoms-causes/syc-20354717