Lead is an element that everyone can safely be against. Lead causes
anemia, hypertension, and brain and kidney damage, and in children stunts
growth and causes permanent cognitive impairment and increased aggressive
behavior. For human health, lead clearly causes harm and does no good.
Ironically, virtually all the lead in the environment is there as a
result of human activity. Under premetallurgical conditions, lead in the earth's
crust was locked safely away in deep ore deposits or in marine calcareous
beds. As technology advanced, lead was mined and smelted and was a workable
and useful metal, finding its way into such diverse applications as Roman
water conduits, medieval cathedral roof sheathing, fine crystal, paints with
a superior covering characteristic, solders, antiknock compounds for automotive
fuels, and, of course, ammunition—ammunition by the countless ton over
the last several hundred years. All that lead was transferred through human
activity, from deep ore deposits to the superficial layers of the earth's
crust in which food is grown.