Children between 1 and 6 years of age are most at risk for lead poisoning. It is caused by breathing or swallowing lead, but is 100% preventable. If you live in a home built before 1978, or are visiting relatives that do, be sure to frequently wash your child's hands, toys, and anything that they may put in their mouth. Routinely wipe down surfaces to clean up any lead dust, and pick up paint chips on the floor and near window sills. http://msue.anr.msu.edu/program/info/lead