You will observe with concern how long a useful truth may be known and exist before it is generally received and praticed on. - Benjamin Franklin (1786) / history of leaded gazoline

Also a way to measure the age of earth - 4.55 billion years old.

There is no safe level of lead

• 2000th americans had 1000x more lead in there body than their ancestors.
• the world is less intelligent today because of leaded gazoline
• Native lead is rare in nature. Currently lead is usually found in ore with zinc, silver and copper and it is extracted together with these metals. - Chemical properties of lead

The latin word for lead - chemical symbol Pb - is plumbum which means liquid silver, resembling when melted, quicksilver otherwise known as mercury, when lead is in the molten state. These words came into being long before the scientific concept of elements was understood.