Lead is a dense toxic heavy metal found in pipes, batteries, coal ash, paint products, and gasoline. Its neurotoxicity was recognized in the late 19th century, as it accumulates in soft tissues and bones in humans, damaging the nervous system and interfering with enzyme function. Even though lead was supposed to fazed out, it is still found in the air, soil, and water, and traces of lead continue to be found in industrial and construction products. Populations are still affected by environmental exposure. Lead is especially toxic to children, as evidenced in the following studies and articles below, contributing to gastrointestinal problems, psychological issues, acute encephalopathy, and lower IQ, as well as contributing to neurological disorders such as autism, ADHD, and behavioral problems.