Lead causes multisystem toxicity. The
classical symptoms of lead intoxication are often nonspecific, including
nausea, vomiting, gastrointestinal pain, constipation, and neurological
symptoms such as inability to concentrate, hyperactivity, and irritability.
Subclinical effects, such as diminished cognitive ability, are notable in
children with even very low blood lead levels (BLL); the BLL threshold
for toxicity has not been identified to date because of technical limitations
in the most widely used clinical laboratory methods